Ravuconazole

Systematic (IUPAC) name
4-[2-[(2R,3R)-3-(2,4-Difluorophenyl)-3-hydroxy-4-(1,2,4-triazol-1-yl)butan-2-yl]-1,3-thiazol-4-yl]benzonitrile
Clinical data
Legal status	?
Identifiers
CAS number	182760-06-1
ATC code	None
PubChem	CID 467825
ChemSpider	411041
NIAID ChemDB	057176
Chemical data
Formula	C22H17F2N5OS
Mol. mass	437.465086 g/mol

ER-30346 is synthesized by thiazole ring formation of (2R, 3R) -3- (2,4-difluorophenyl) -3-hydroxy-2-methyl-4- (1H-1,2,4-triazol-1-yl ) thiobutanamide (I) and 4-bromoacetylbenzonitrile (II) by means of reflux in methanol. The thioamide (I) is obtained with excellent yield from a chiral nitrile (III) by heating with diethyl dithiophosphate in aqueous medium.

The nitrile (III), a chiral key intermediate of this synthesis, can be obtained by two different synthetic routes as follows: Route-a: The key step of this route is ring opening reaction of the trisubstituted oxirane (VII) by cyanide anion leading to the nitrile (III). The chiral oxirane (VII) is synthesized from (R) -lactic acid derivatives as already reported. The reaction of (VII) with diethylaluminum cyanide in toluene or lithium cyanide in tetrahydrofuran gives the nitrile (III) with high yield without any epimerization reaction.

The nitrile (III), a chiral key intermediate of this synthesis, can be obtained by two different synthetic routes as follows: Route-b: The starting material of this route is methyl (S) -3-hydroxy-2-methylpropionate (VIII ), which contains one additional carbon between the hydroxyl group and the 2-position carbon of (R) -lactate, the starting material of route-a. The hydroxyl group of (VIII) is protected by triphenylmethyl group. Then, 2,4 -difluorophenyl moiety is introduced to give the ketone (X). Direct conversion of the ketone (X) to the oxirane (XIV) by dimethylsulfoxonium methylide, the same condition for compound (IV) in route-a, does not proceed. The oxirane (XIV) having desired stereochemistry is obtained via oxidation reaction. The ketone (X) is converted to the exomethylene (XI) by Wittig reaction. The stereoselective oxidation of (XI) is achieved by means of osmium tetroxide in the presence of 4-methylmorpholine N-oxide to give the diol (XII) in 58% yield after separation of its epimer by column chromatography. After methanesulfonylation of the primary alcohol of (XII), a triazole moiety is introduced and the triphenylmethyl group is deprotected. Then, the primary hydroxyl group of (XVI) is oxidized under Swern oxidation condition to give the aldehyde (XVII), which is converted to the chiral nitrile intermediate (III) by means of heating with hydroxylamine-O-sulfonic acid.

The synthesis of (2S, 3S) -3- (2,4-difluorophenyl) -3-hydroxy-2-methyl-4- (1,2,4-triazol-1-yl) butyronitrile (XV), a key intermediate the synthesis of ER-30346 has been described: The tritylation of 3-hydroxy-2 (S) -methylpropionic acid methyl ester (I) with trityl chloride in hot pyridine gives the trityl ether (II), which is hydrolyzed with LiOH in H2O / THF / methanol yielding the free acid (III). The esterification of (III) with 2-mercaptopyridine (IV) by means of dicyclohexylcarbodiimide (DCC) in dichloromethane gives the thioester (V), which is treated with 2,4-difluorophenylmagnesium bromide (VI) in THF yielding the propiophenone (VII), which by treatment with methyltriphenylphosphonium bromide / NaH in THF is converted into the methylene derivative (VIII). The oxidation of (VIII) with OsO4 and N-methylmorpholine oxide in acetone affords, after column chromatography, the chiral diol (IX), which is monomesylated with mesyl chloride / triethylamine in dichlormethane giving the monoester (X). The reaction of (X) with 1,2,4-triazol (XI) and NaH in DMF yields (2R, 3S) -2- (2,4-difluorophenyl) -3-methyl-1- (1,2,4-triazol-1-yl) -4- (triphenylmethoxy) -2-butanol (XII), which is detritylated with p-toluenesulfonic acid in methanol affording the diol (XIII). The oxidation of (XIII) with oxalyl chloride / DMSO in dichloromethane gives the aldehyde (XIV), which is finally treated with hydroxylamine-O-sulfonic acid in water yielding the desired bytyronitrile intermediate (XV) already referenced.

http://www.google.com/patents/WO2011042827A1?cl=en

Example 1

(2R,3R)-3-i4-(4-cvanophenyl)thiazol-2-yl1-1 -(1 H-1 ,2,4-triazol-1 -yl)-2-(2,4-difluorophenyl)- butan-2-ol

To a solution of racemic 3-[4-(4-cyanophenyl)thiazol-2-yl]-1 -(1 H-1 ,2,4-triazol-1 -yl)-2-(2,4- difluorophenyl)-butan-2-ol (43.7 g) in acetone (800 ml) a solution of (1 R)-10- camphorsulfonic acid (23 g) in methanol (300 ml) was added and the mixture was heated under reflux until a clear solution was obtained. The solution was slowly cooled to rt, seeded with crystals of the title enantiomeric salt and let overnight. The solid was collected by filtration, washed with acetone and dried to provide (2R,3R)-3-[4-(4- cyanophenyl)thiazol-2-yl]-1 -(1 H-1 ,2,4-triazol-1 -yl)-2-(2,4-difluorophenyl)-butan-2-ol (1 R)- 10-camphorsulfonate as white solid. This crude salt was then taken up in methylenechloride (100 ml) and water (ca. 100 ml) and the mixture was basified with aqueous sodium hydroxide solution. The organic layer was separated and the aqueous phase washed twice with methylenechloride (50 ml) and combined. The organic phases were then washed twice with water (2×50 ml), dried with sodium sulfate, filtrated and the solvent removed under reduced pressure. The crude product was then mixed with isopropanol (ca. 150 ml), heated for 10 min, cooled to 0^° C and stirred for ca. 2 hrs. The product was collected, washed with isopropanol and dried under reduced pressure to provide the enantiomerically pure title compound (17.5 g, 41 % yield, 99.1 % ee); m.p. 164-166^° C; [a]=-30^° (c=1 , methanol, 25^° C); NMR (CDCI3): 1 .23(3H, d, J=8 Hz), 4.09(1 H, q, J=8Hz), 4.26(1 H, d, J=14Hz), 4.92(1 H, d, J=14Hz), 5.75(1 H, s), 6.75- 6.85(2H, m), 7.45-7.54(2H, m), 7.62(1 H, s), 7.69(1 H, s), 7.75(1 H, d, J=8Hz), 7.86(1 H, s), 8.03(1 H,d,J=8Hz). The analytical data were identical with published (US5648372 and Chem. Pharm. Bull. 1998, 46, 623-630).

…………………………

http://www.google.com/patents/WO1999045008A1?cl=en

Example 1

a) Preparation of (2R)-2′,5′-Difluoro-2-(3,4,5,6-tetrahydro-

2H-pyran-2-yloxy)-propiophenone A mixture of magnesium ( 7.25 g, 0.298 mol ) and iodine ( catalytic amount ) and l-bromo-2,5-difluorobenzene ( 20.0 g, 0.178 mol ) in THF ( 250ml ) was vigously stirred. The color of iodine was disappeared and the inner temperature rose up to 65°C. To this mixture was added additional l-bromo-2,5-difluorobenzene ( 30.0 g, 0.267 mol ) dropwise to maintain the inner temperature from 50 to 55°C over 45min. The resulting mixture was stirred at 55°C for 30min. then at r.t. for lhr. The – 21 -

mixture was cooled down to -5°C. To this mixture was added a solution of.4-[(2R)-2-(3,4,5,6-Tetrahydro-2H-pyran-2-yloxy)propionyl] morpholine ( 52.5 g, 0.216 mol ) in THF ( 150ml ) dropwise over 40min. And the resulting mixture was stirred at r.t. for 4hrs. The reaction mixture was cooled down to 5°C and saturated NH4C1 aq. ( 100ml ) was added carefully. The whole was diluted with H20 ( 600ml ) and extracted with EtOAc ( 400ml + 200ml x 2 ). The combined organic layer was dried over Na2S04 and concentrated in vacuo. The residue was chromatographed on silica gel ( n-hexane : EtOAc = 10 :1 ~ 5 : 1 ) to give (2R)-2′,5′- Difluoro-2-(3,4,5,6-tetrahydro-2H-pyran-2-yloxy)-propiophenone (47.3 g,

81 % ) as pale yellow syrup.

Physical form : colorless oil; FAB-MS: m/z 271(M+H)⁺; Η-NMR(CDCl_;j): 1.42~1.90(9H,m),3.32~3.40(lHxl/2,m),3.69~3.77(lHxl/2,m),3.86~3.94 (lHxl/2,m),4.66(lHxl/2,t,J=3.6Hz),4.75(lHxl/2,t,J=3.6Hz),4.87(lHxl/2, q,J=6.6Hz),5.11(lHxl/2,q,J=6.9Hz),7.08~7.25(2H,m),7.49~7.55(lH,m).

b) Preparation of 2-(2,5-Difluorophenyl)-2-[(lR)-l-(3,4,5,6,- tetr ahy dro-2H-pyran-2-yloxy ) ethyl] oxir ane To a stirred mixture of NaH ( 60% in oil, 9.1g, 0.228mol ) in DMSO

(300ml ) was added portionwise trimethylsulfoxonium iodide ( 53.9g, 0.245 mol ) at the inner teperature with the range from 15°C to 18°C. over 20min. The ice bath was removed and the mixtuer was stirred at r.t. for 3hrs. The mixture was cooled down to 10°C. To this mixture was added a solution of (2R)-2′,5′-Difluoro-2-(3,4,5,6-tetrahydro-2H-pyran-2- yloxy)-propiophenone ( 47.3 g , 0.175 mol ) in DMSO (150ml ) dropwise over 20min. The resulting mixture was stirred at r.t. for 4hrs. The reaction mixture was poured into ice-water ( 800ml ). The whole was extracted with EtOAc ( 400ml + 200ml x 2 ). The combined organic layer was washed with brine, dried over Na2S04 and concentrated in vacuo.

The residue was chromatograkkphed on silicagel ( n-hexane : EtOAc = – 22 -

8 : 1 ~ 5 : 1 ) to give 2-(2,5-Difluorophenyl)-2-[(lR)-l-(3,4,5,6,- tetrahydro-2H-pyran-2-yloxy)ethyl]oxirane (48.3 g, 97 % ). Physical form : pale yellow syrup, EI-MS: m/z 284 (M)⁺ ; ¹H-NMR(CDC1₃): 1.15(3Hxl/2,dd,J=6.6,1.3Hz), 1.24(3Hxl/2,dd, J=6.6,1.3Hz), 1.52-1.87 (6H,m),2.83~2,90(lH,m),3.07

(lHxl/2,d,J=5.3Hz),3.36(lHxl/2,d,J=5.6Hz), 3.48~3.56(lH,m),3.82~3.92 (lH,m),4.00~4.16(lH,m),4.73~4.92(lH,m), 6.96~7.02(lH,m),7.09~7.15 (lH,m).

c) Preparation of (3R)-2-(2,5-difluorophenyl)-3-(3,4,5,6- tetrahydro-2H-pyran-2-yloxy)-l-(lH-l,2,4-triazol-l-yl)-2-butanol

To a stirred suspension of NaH ( 60 % in oil, 21.0 g, 0.525 mol ) in DMF (300ml ) was added portionwise 1,2,4-triazole ( 43.3 g, 0.627 mol ) at the inner temperature from 2°C to 11°C over 30min. The resulting mixture was stirred at r.t. for l.δhrs. To this mixture was added a solution of 2-(2,5-Difluorophenyl)-2-[(lR)-l-(3,4,5,6-tetrahydro-2H- pyran-2-yloxy)ethyl]oxirane ( 48.3 g, 0.170 mol ) in DMF ( 50 ml ). The mixture was stirred at 60°C for lhr. and then at 65°C for 14hrs. The reaction mixture was cooled down to 10°C and then poured into ice- water (800 mL ). The resulting mixture was extracted with EtOAc

(400ml + 200ml x 2 ). The combined organic layer was dried over Na2S04 and concentrated in vacuo. The residue was chromatographed on silicagel ( n-hexane : EtOAc = 4 : 1 ~ 1 : 5 ) to give (3R)-2-(2,5- difluorophenyl)-3-(3,4,5,6-tetrahydro-2H-pyran-2-yloxy)-l-(lH-l,2,4- triazol-l-yl)-2-butanol ( 43.9 g, 73 % ) and recovered starting material

(13.2 g, 27 % ).

Physical form : colorless syrup ; FAB-MS: m/z 354 (M+H)⁺ ; Η- NMR(CDCl₃): 1.00(3Hxl/2,d,J=6.6Hz),1.13(3Hxl/2,d,J=6.6Hz), 1.42~1.88(6H,m),3.38~3.60 (lH,m),3.80~4.00(lH,m),4.32~5.02(5H,m),6.83~6.99 (2H,m),7.14-7.21

(lH,m),7.73(lHxl/2,s),7.74(lHxl/2,s),7.92(lHxl/2,s),7.95(lHxl/2,s). – 23 -

d) Preparation of (2R,3R)-2-(2,5-difluorophenyl)-l-(lH-l,2,4- triazol-l-yl)-2,3-butanediol

A mixture of (3R)-2-(2,5-difluorophenyl)-3-(3,4,5,6-tetrahydro-2H- pyran-2-yloxy)-l-(lH-l,2,4-triazol-l-yl)-2-butanol ( 43.9 g, 0.124 mol ) and PPTS ( 15.6 g, 62.1 mmol ) in EtOH ( 400ml ) was stirred at 55°C for 5hrs. The mixture was was evaporated to remove solvent down to 100ml. The residue was poured into ice-aqueous NaHC03 ( 500ml ). The whole was extracted with EtOAc ( 400ml + 200ml x 2 ). The combined organic layer was dried over Na2S04 and concentrated in vacuo. The residue was chromatographed on silicagel (CH2C12 : MeOH = 20 : 1) to give (2R,3R)-2-(2,5-difluorophenyl)-l-(lH-l,2,4-triazol-l-yl)-2,3- butanediol (18.0 g, 54 % ). Physical form : colorless syrup ; FAB-MS: m/z 270 (M+H)’ ; ‘H- NMR(CDC1₃): 0.99(3H,d,J=6.6Hz),2.61(lH,d,J=10.6Hz), 4.31-4.36

(lH,m),4.79,4.88

(2H,ABq,J=14.5Hz),4.84(lH,s),6.84~6.99(2H,m),7.13~7.19(lH,m),7.84(l H,s),7.85(lH,s).

e) Preparation of (2R,3S)-2-(2,5-Difluorophenyl)-3-methyl-2-

[ ( 1H- 1 ,2,4-triazol-l -yl) -methyl] -oxir ane

To a cold ( 0°C ) and stirred solution of (2R,3R)-2-(2,5-difluorophenyl)- l-(lH-l,2,4-triazol-l-yl)-2,3-butanediol ( 35.0 g, 0.130 mol ) and triethylamine ( 54.8 ml, 0.393 mol ) in CH2C12 ( 500ml ) was added a mesylchloride ( 12.1 ml, 0.156 mol ) dropwise over 5min. The resulting mixture was stirred at r.t. for l.δhrs. The reaction mixture was poured into ice-water ( 300ml ). The resulting mixture was shaken well and the organic layer was separated. The aqueous layer was further extracted with CH2C12 ( 150ml x 2 ). All the organic layers were combined, dried over Na2SO4 and concentrated in vacuo to give mesylate ( 46.7 g ) as crude syrup. The obtained mesylate was dissolved in MeOH ( 500ml ) – 24 -

and the solution was cooled down to 0°C. To this solution was added 28% NaOMe methanol solution (29.0 ml ). The mixture was stirred at 0°C for 50min. The reaction mixture was evaporated to reduce the volume of the solvent down to 150 ml. The residue was poured into ice- water ( 300ml ). The resulting mixture was extracted with ethylacetate (300ml + 200ml x 2 ). The combined organic layer was dried over Na.,S0 and concentrated in vacuo. The residue was cromatographed on silicagel (hexane : EtOAc = 1 : 3 ) to give (2R,3S)-2-(2,5-Difluorophenyl)- 3-methyl-2-[(lH-l,2,4-triazol-l-yl)-methyl]-oxirane (30.3 g, 93 %).

Physical form : white solid ; FAB-MS : m z 252 (M+H)⁺ ; ^]H- NMR(CDC1₃): 1.64(3H,d,J=5.6Hz),3.19(lH,q,J=5.6Hz),4.42,4.97 (2H,ABq,J=14.8Hz), 6.75~6.81(lH,m),6.89~7.01(2H,m),7.83(lH,s),7.98 UH,s).

f) Preparation of (2S,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-

2-methyl-4-[l,2,4]triazol-l-yl-butyronitrile

A mixture of (2R,3S)-2-(2,5-Difluorophenyl)-3-methyl-2-[(lH-l,2,4- triazol-l-yl)-methyl]-oxirane ( 30.3 g, 0.121 mol ), trimethylsilylcyanide ( 65.0 ml ) and MgO ( 24.5 g ) in o-xylene ( 400 ml ) was stirred at 130°C for lOhrs. To this mixture was added additional trimethylsilylcyanide (20.0 ml ) and MgO ( 8.5 g ) and the resulting mixture was stirred at 130°C further for 6hrs. The reaction mixture was cooled down to r.t. The precipitate was filtered off and washed with CH2C12. The filtrate was concentrated in vacuo to give crude brown syrup.

This crude syrup was dissolved in THF ( 600ml ) and the solution was cooled down to 0°C. To this mixture was added 1.0 M tetra n- butylammoniumfluoride THF solution ( 133ml, 0.133 mol ) dropwise over 5min. The mixture was stirred at r.t. for 50min. The solvent was removed under reduced pressure down to 150ml. The residue was poured into ice-water ( 400ml ). The resulting mixture was extracted – 25 -

with EtOAc ( 300ml + 200ml x 2 ). The combined organic layer was dried over Na2SO4 and concentrated in vacuo. The residue was chromatographed on silicagel ( n-hexane : EtOAc = 1 : 3 ) to give (2S,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-2-methyl-4-[l,2_;4]triazol-l-yl- butyronitrile ( 30.5 g, 91 % ).

Physical form : colorless syrup ; FAB-MS : m/z 279 (M+H)⁺ ; Η- NMR(CDCl₃): 1.19(3H,d,J=7.3Hz),3.33(lH,q,J=7.3Hz),4.82,5.00 (2H,ABq,J=13.9Hz), 5.56(lH,brs),6.89~7.04(2H,m),7.12~7.19(lH,m),7.85(lH,s),7.86(lH,s).

g) Preparation of (2R,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-

2-methyl-4- [ 1 ,2,4] triazol-1 -ylthiob tyramide

A mixture of (2S,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-2-methyl-4- [l,2,4]triazol-l-yl-butyronitrile ( ³⁰-⁵ S> O.llOmol ), diethyldithio- phospate ( 235 ml ) and H2O ( 110 ml ) was stirre at 80°C for 2hrs. The reaction mixture was cooled down to r.t. n-Hexane ( 400ml ) and water (200 ml ) was added. The whole was shaken well and the aqueous layer was separated. The remaining organic layer was further extracted with H20 ( 100ml x 3 ). All the aqueous layer was combined. Cooled down to

0°C and neutralized and basified ( PH8 ) with NaHC03. This basic(PH8) aqueous layer was extracted with EtOAc ( 300ml + 100ml x 3 ). The combined organic layer was dried over Na2S04 and concentrated in vacuo to give dark brown syrup. By addition of CH2C12 ( 100ml ) to this crude syrup, precipitate was formed. The precipitate was filtered and washed with CH2C12-hexane ( 5 : 1 mixture ) to give (2R,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-2-methyl-4-[l,2,4]triazol-l- ylthiobutyramide ( 19.2 g, 56 % ) as white powder. On the oter hand, the filtrate was concentrated in vacuo and the residue was chromatographed on silica gel ( Wako-gel C-300, CH2C12 : MeOH = 20 :

1 ) to give additional (2R,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-2- – 26 -

methyl-4-[l,2,4]triazol-l-ylthiobutyramide ( 7.46 g, 22 % ) as pale brown amorphous powder.

Physical form : White solid ; FAB-MS : m/z 313 (M+H)⁺ ; ‘H-NMR (CDC1₃): 1.12(3H,d,J=7.3Hz),3.74(lH,q,J=7.3Hz), 4.55,5.12 (2H,ABq,J=14.5Hz), 5.84(lH,s),6.85~7.02(2H,m),7.15-7.22(lH,m),7.80

(1H,S),7.89(1H,S), 7.89(lH,brs),8.43(lH,brs).

h) Preparation of 4-{2-[(lR,2R)-2-(2,5-Difluoro-phenyl)-2- hydroxy-l-methyl-3-[l,2,4]triazol-l-yl-propyl]-thiazol-4-yl}- benzonitrile

A mixture of (2R,3R)-3-(2,5-Difluoro-phenyl)-3-hydroxy-2-methyl-4- [l,2,4]triazol-l-ylthiobutyramide ( 26.7 g, 85.4 mmol ) and a-bromo-4′- cyano-acetophenone ( 24.0 g, 0.107 mol ) in EtOH ( 500ml ) was refluxed for lhr. The reaction mixture was cooled down to r.t. And the solvent was removed under reduced pressure down to 150ml. The residue was poured into in to cold ( 0°C ) saturated NaHC03 aq. ( 400ml ). The resulting mixture was extracted with EtOAc ( 300ml + 150 ml x 2 ). The combined organic layer was washed with brine (200ml ), dried over Na2S04 and concentrated in vacuo. The residue was chromatographed on silica gel ( Wako-gel C-300, Hexane : EtOAc = 1 : 2 ) to give 4-{2-

[(lR,2R)-2-(2,5-Difluoro-phenyl)-2-hydroxy-l-methyl-3-[l,2,4]triazol-l- yl-propyl]-thiazol-4-yl}-benzonitrile ( 32.0 g, 86 % ).

Physical form : colorless heavy syrup ; ESI-MS : m/z 437 (M)⁺ ; ‘H-

NMR(CDCl₃): 1.25(3H,d,J=7.3Hz),4.12(lH,q,J=7.3Hz),4.26,4.96 (2H,Abq,J=14.5Hz), 5.75(lH,s),6.89~7.07(2H,m),7.23~7.29(lH,m),7.65

(lH,s),7.71(lH,s),7.75,8.02 (4H,Abq,J=8.6Hz),7.85(lH,s). – 27 -

i) Preparation of 4-{4-[(tert-Butoxycarbonyl-methyl-amino)- acetoxy]-3,5-dimethyl-benzyl}-l-[(2R,3R)-3-[4-(4-cyano-phenyl)- thiazol-2-yl]-2-(2,5-difluoro-phenyl)-2-hydroxy-butyl]-lH- [l,2,4]triazol-4-ium bromide A mixture of 22.7mg of 4-{2-[(lR,2R)-2-(2,5-Difluoro-phenyl)-2-hydroxy- l-methyl-3-[l,2,4]triazol-l-yl-propyl]-thiazol-4-yl}-benzonitrile and 25.0mg of 4-tert-butoxycarbonyl-methyl-aminoacetoxy-3,5-dimethyl- benzyl bromide in CH₃CN(1.5mL) was refluxed over 15hrs. The solvent was evaporated in vacuo and the residue was chromatographed on silica gel (Wakogel C-200, solvent:CH₂Cl MeOH=10/l) to give 4-{4-[(tert-

Butoxycarbonyl-methyl-amino)-acetoxy]-3,5-dimethyl-benzyl}-l- [(2R,3R)-3-[4-(4-cyano-phenyl)-thiazol-2-yl]-2-(2,5-difluoro-phenyl)-2- hydroxy-butyl]-lH-[l,2,4]triazol-4-ium bromide (36.0mg, 84% as colorless heavy syrup) ; FAB-MS : m/z 743 (M-Br)’ ; Η-NMR(CDC1_S): 1.23(3H,d,J=7.3Hz),

1.47(9H,s),2.14(6H,s),3.03(3H,s),4.15(lH,q,J=7.3Hz),4.25(2H,s), 4.98,5.16(2H,ABq,J=13.9Hz),5.39~5.54(2H,m),6.27(lH,s),6.89-7.07(4H, m),7.24~7.27(lH,m),7.58(lH,s),7.73,8.06(4H,ABq,J=8.58),8.07(lH,s),ll. 26 (lH,s).

j) Preparation of l-{(2R,3R)-3-[4-(4-cyano-phenyl)-thiazol-2-yl]- 2-(2,5-difluoro-phenyl)-2-hydroxy-butyl}-4-(3,5-dimethyl-4- methylaminoacetoxy-benzyl)-lH-[l,2,4]triazol-4-ium bromide To a solution of 36mg of 4-{4-[(tert-Butoxycarbonyl-methyl-amino)- acetoxy]-3,5-dimethyl-benzyl}-l-[(2R,3R)-3-[4-(4-cyano-phenyl)-thiazol-

2-yl]-2-(2,5-difluoro-phenyl)-2-hydroxy-butyl]-lH-[l,2,4]triazol-4-ium bromide in ethylacetate(2ml) was added dropwise 4N HC1 ethylacetate solution(lmL) and the mixture was stirred at r.t. for 4hrs.The precipitate was ^“filtered and washed with diethylether to give 1- {(2R,3R)-3-[4-(4-cyano-phenyl)-thiazol-2-yl]-2-(2,5-difluoro-phenyl)-2- hydroxy-butyl}-4-(3,5-dimethyl-4-methylaminoacetoxy-benzyl)-lH- – 28 -

[l,2,4]triazol-4-ium bromide (24.5mg, 74% as HC1 salt and as white solid) ;

FAB-MS : m/z 643 (M-Br)⁺ ; Η-NMR(DMSO-d): 1.19(3H,d,J=7.3Hz), 2.11(6H,s),2.64(3H,s),4.15(lH,q,J=7.3Hz),4.41(2H,s),4.74,5.04(2H,ABq,J =14.5Hz),5.40(2H,s),6.76(lH,brs),7.10(2H,s),7.20~7.38(2H,m), 7.94,8.21

(4H,ABq,J=8.25),8.45(lH,s),9.07(lH,s),9.50(lH,brs),10.17(lH,s).

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http://www.google.co.in/patents/US5648372

OR

http://www.google.co.in/patents/EP1394142A1

COMPD 21

Example 88:Preparation of a compound of the structural formula:
•  
•  
  2-(2,4-Difluorophenyl)-3-thioamide-1-(1H-1,2,4-triazol-1-yl)-2-butanol (the raw material 2) (156 mg) was dissolved in EtOH (2 ml), and 2-bromo-4′-cyanoacetophenone (the raw material 3) (224 mg) was added to the solution, followed by heating and refluxing for 1 hour. The liquid reaction mixture was neutralized with a saturated aqueous solution of NaHCO₃ and subjected to extraction with AcOEt. After the extract was washed with H₂O and then a saturated aqueous solution of NaCl and dried over MgSO₄, AcOEt was distilled out. The resultant residue was purified by chromatography on silica gel (SiO₂: 20 g, eluted with CH₂Cl₂ and then with 1% solution of MeOH in CH₂Cl₂), and then crystallized from IPE, thereby obtaining the intended compound (109 mg). Physical properties of this compound are described below.

  mp:

  196-197°C.

  NMR:

  δ solvent (CDCl₃)
  1.23(3H,d,J=8.0Hz), 4.09(1H,q,J=8.0Hz), 4.26(1H,d,J=14.3Hz), 4.92(1H,d,J=14.3Hz), 5.74(1H,s), 6.78-6.85(2H,m), 7.48-7.54(1H,m), 7.64(1H,s), 7.69(1H,s), 7.75(1H,d,J=8.1Hz), 7.85(1H,s), 8.03(1H,d,J=8.1Hz).

  MS:

  MH⁺ = 438.

References

Literature References:

Ergosterol biosynthesis inhibitor. Prepn (stereochemistry unspecified): T. Naito et al, EP 667346; eidem,US 5648372 (1995, 1997 both to Eisai); of optically acitve form: A. Tsuruoka et al., Chem. Pharm. Bull. 46, 623 (1998). Chiral synthesis: Y. Kaku et al., ibid. 1125.

In vitro comparative antifungal spectrum: J. C. Fung-Tomc et al., Antimicrob. Agents Chemother. 42, 313 1998. Antifungal activity in candidosis: K. V. Clemons, D. A. Stevens, ibid. 45, 3433 (2001); in aspergillosis: W. R. Kirkpatrick et al., J. Antimicrob. Chemother. 49, 353 (2002).

Clinical evaluation in onychomycosis: A. K. Gupta et al., J. Eur. Acad. Dermatol. Venereol. 19, 437 (2005).

Review of development and therapeutic potential: S. Arikan, J. H. Rex, Curr. Opin. Invest. Drugs 3, 555-561 (2002).

Extras you may need

http://www.google.com/patents/WO2011042827A1?cl=en

Scheme 1 :

The manufacturing process for Isavuconazole is similar: Since Isavuconazole differentiates from Ravuconazole by only another fluorine substitution on the aromatic ring (2,5- instead of 2,4-difluorophenyl), the identical synthesis has been used (US 6300353 from October 9, 2001 and Bioorg. & Med. Chem. Lett. 13, 191 (2003)). Consequently, also this manufacturing process, based on (R)-lactic acid, faces the same problems: to many steps, extremely low overall yield and in addition to US patent 6300353 claims even already known step as novel (claim 36).

Recent attempts to improve this concept as reported in WO 2007/062542 (Dec.1 , 2005), using less expensive, natural configured (S)-lactic acid, also failed: As already reported in US 6133485 and in US 2003/0236419, the second chiral center was formed from an optically active allyl alcohol prepared in a few steps from (S)-lactic acid. This allyl alcohol was subjected to Sharpless diastereoselective epoxidation providing first an opposite configured, epimeric epoxy alcohol which had to be then epimerized in an additional inversion step yielding finally the desired epoxy alcohol as the known precursor for Isavuconazole (US 6300353). It is obvious that this process using less expensive (S)- lactic acid makes the entire process with an inversion step even more complex than the original approach.

Elegant and more efficient process has been claimed in US 2004/0176432 from June 26, 2001 ) in which both chiral centers have been formed simultaneously, diastereo- and enantio-selectively pure in one single reaction step using chiral (R)-2-butynol as a chiral precursor in the presence of Pd(ll)-catalyst and diethyl zinc (Scheme 2).

Scheme 2:

Since water soluble, (R)-2-butynol is expensive, recently identical process has been published, in which instead of (R)-2-butynol less water soluble and therefore, less expensive (R)-4-phenyl-3-butyn-2-ol was used (Synthetic Commun. 39, 161 1 (2009)). Nevertheless, as incorrectly stated there, this process does not provide better diastereoselectivity than the original process using (R)-2-butynol: On the contrary disadvantage of this process is a very bad atom economy because huge phenyl group of (R)-4-phenyl-3-butyn-2-ol has to be “disposed” in oxidation step by the conversion of triple bond into carboxylic acid function.

……………………………

http://www.google.com/patents/WO2014023623A1?cl=en

The invention relates to a process for the manufacture of a

diastereomerically and enantiomerically enriched ester intermediate for isavuconazole or ravuconazole.

Isavuconazole and ravuconazole are triazole antifungal compounds. Processes for the manufacture of isavuconazole and ravuconazole were disclosed in patents WO99/45008, WO2007/062542 and WO03/002498 to Basilea. In WO2011/042827 a process for the manufacture of enantiomerically pure antifungal azoles such as ravuconazole and isavuconazole is disclosed, wherein a classical resolution of a racemic mixture is performed by the addition of an enantiopure chiral acid, then collection of the desired diastereomer followed by conversion of the salt into the enantiomerically pure form of the desired compound by treatment with a base or an ion-exchange resin. The disadvantages of using such classical resolution are that the chiral auxiliary needs to be applied in near stoichiometric amounts, and that additional process steps are required for recovery of these relatively high amounts of chiral reagent as well as for converting the salt into the free enantiopure product.

http://www.google.com/patents/US8076494

Reaction Scheme 1:

Fosravuconazole

Phosphoric acid 2(R)-[4-(4-cyanophenyl)thiazol-2-yl]-1(R)-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-ylmethyl)propyoxymethyl monoester

(2R,3R)-3-r4-(4-cyanophenyl)thiazol-2-yll-2-(2,4-difluorophenyl)- 1 -(1 H- 1 ,2,4- triazol-l-yl)-2-[(dihydrogen phosphonoxy)methoxylbutane

BEF-1224
BMS-379224
E-1224

Phosphoric acid 2(R)-[4-(4-cyanophenyl)thiazol-2-yl]-1(R)-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-ylmethyl)propyoxymethyl monoester bis(L-lysine) salt is used as drug

The azole antifungal agent E-1224 is a prodrug of ravuconazole. In 2009, originator Eisai licensed E-1224 to Drugs for Neglected Diseases Initiative for the treatment of American trypanosomiasis (Chagas disease) in Latin America and the Caribbean. DNDi was conducting phase II clinical trials with the prodrug for this indication, however, development of the compound has been discontinued due to lack of sustained efficacy. Ravuconazole was originally licensed by Eisai to Bristol-Myers Squibb (BMS). BMS developed the drug’s prodrug, referred to by BMS as BMS-379224. For strategic reasons, BMS did not pursue development of the compound. In 2010, E-1224 was licensed exclusively to Brain Factory for development, commercialization and sublicense in Japan for the treatment of fungal infections.

About Ravuconazole and Ravuconazole Prodrug
The compound on the left is ravuconazole; the compound on the right is the dihydrogen phosphonoxy methoxy derived ravuconazole prodrug which has improved solubility and bioavailability.

……………………………………………………………

WO 2001052852

 http://www.google.com/patents/WO2001052852A1?cl=en

Triazole antifungal compounds are well known in the prior art. Of the several classes known, one particularly potent class contains a tertiary hydroxyl group. For example, U. S. Patent 5,648,372 discloses that (2R,3R)-3-[4-(4- cyanophenyl)thiazol-2-yl]-2-(2,4-difluorophenyl)- 1 -( 1 H- 1 ,2,4-triazol- 1 -yl)- butan-2-ol has anti-fungal activity.

The utility of this class of compounds is limited by their low water solubility. For example, the solubility of the above triazole compound in water at pH 6.8 is 0.0006 mg/mL. This greatly impedes developing suitable parenteral dosage forms.

One method of addressing this problem was disclosed in European Patent Application 829478, where the water solubility of an azole antifungal agent was increased by attaching a linked amino-acid to the azole portion of the molecule

Alternatively, WO 97/28169 discloses that a phosphate moiety can be attached directly to the tertiary hydroxyl portion of the anti-fungal compound, e.g. the compound having the formula

U.S. Patent 5,707,977 and WO 95/19983 disclose water soluble prodrugs having the general formula

wherein X is OP(O)(OH)₂ or an easily hydrolyzable ester OC(O)RNR l’rR>2.

WO 95/17407 discloses water-soluble azole prodrugs of the general formula

wherein X is P(O)(OH)₂, C(O)-(CHR’)_n-OP(O)(OH)₂ or C(O)-(CHR’)_π

-(OCHR^,CHR¹)_mOR₂.

WO 96/38443 discloses water-soluble azole prodrugs of the general formula

U.S. Patent 5,883,097 discloses water-soluble amino acid azole prodrugs such as the glycine ester

The introduction of the phosphonooxymethyl moiety into hydroxyl containing drugs has been disclosed as a method to prepare water-soluble prodrugs of hydroxyl containing drugs.

European Patent Application 604910 discloses phosphonooxymethyl taxane derivatives of the general formula

wherein at least one of R^{1 ‘}, R^2″, R^3′, R^6′ or R^7′ is OCH₂OP(O)(OH)₂.

European Patent Application 639577 discloses phosphonooxymethyl taxane derivatives of the formula T-[OCH₂(OCH₂)_mOP(O)(OH)₂]_n wherein T is a taxane moiety bearing on the C13 carbon atom a substituted 3-amino-2- hydroxypropanoyloxy group; n is 1, 2 or 3; m is 0 or an integer from 1 to 6 inclusive, and pharmaceutically acceptable salts thereof. WO 99/38873 discloses O-phosphonooxymethyl ether prodrugs of a diaryl 1,3,4-oxadiazolone potassium channel opener.

Golik, J. et al, Bioorganic & Medicinal Chemistry Letters, 1996, 6:1837- 1842 discloses novel water soluble prodrugs of paclitaxel such as

EXAMPLE 1

(2R,3R)-3-r4-(4-cyanophenyl)thiazol-2-yll-2-(2,4-difluorophenyl)- 1 -(1 H- 1 ,2,4- triazol-l-yl)-2-[(dihydrogen phosphonoxy)methoxylbutane, sodium salt

(2R,3R)-3-r4-(4-cyanophenyl)thiazol-2-yll-2-(2,4-difluorophenyl)-l-(lH- 1 ,2,4-triazol- 1 -yl)-2-[(di-tert-butyl phosphonoxy)methoxy1butane

To a solution of (2R,3R)-3-[4-(4-cyanophenyl)thiazol-2-yl]-2-(2,4- difluorophenyl)-l-(lH-l,2,4-triazol-l-yl)butan-2-ol, II, (8.74 g, 20 mmol) in THF (40 mL) under a nitrogen atmosphere was added sodium hydride (0.80 g, 60% in oil, 20 mmol) at rt. The resulting mixture was stirred at rt for 0.25 h and then di- tert-butyl chloromethyl phosphate, III (10.3 g, 40 mmol) was added. The reaction mixture was heated at 50 °C for 16 h. The reaction mixture was then allowed to cool to rt and was concentrated under reduced pressure. The residue was dissolved in Et₂O and was washed with H₂O and brine. The organic layer was dried over MgSO₄ and was concentrated under reduced pressure to obtain 17.0 g of crude subtitled compound. IV, as a gum. A small portion of this crude compound was purified by reverse phase chromatography on C- 18. The column was eluted with 30% CH₃CN/H₂O, 38% CH₃CN/H₂O, 45% CH₃CN/H₂O and then 50% CH₃CN/Η₂O. The product containing fractions were concentrated under reduced pressure in order to remove CH₃CN. The resulting aqueous layer was then extracted with Et₂O. The Et O layers were washed with brine, dried and concentrated under reduced pressure to afford purified subtitled compound, IV, as a white solid. 1H NMR (300 MHz, CDC1₃): δ 8.35 (s, 1H), 7.98 (d, 2H, J=9), 7.76 (s, 1H), 7.71 (d, 2H, J=9), 7.63 (s, 1H), 7.36-7.27 (m, 1H), 6.86-6.78 (m, 2H), 5.53 (dd, 1H, J=28,6), 5.53 (dd, 1H, J=9,6), 5.17 (d, 1H, J=15), 5.03 (d, 1H, J=15), 4.01 (q, 1H, J=7), 1.47 (s, 9H), 1.45 (s, 9H), 1.37 (d, 3H, J=7). MS [ESI⁺ (M+H)⁺] 660.2 obs. B. (2R,3R)-3-r4-(4-cyanoρhenyl)thiazol-2-yll-2-(2,4-difluorophenyl)-l-(lH- 1 ,2,4-triazol-l-yl)-2-[(dihydrogen phosphonoxy)methoxy]butane, sodium saltdeprotection

The crude (2R,3R)-3-[4-(4-cyanophenyl)thiazol-2-yl]-2-(2,4- difluoropheny 1)- 1 -( 1 H- 1 ,2 ,4-triazol- 1 -y l)-2- [(di-tert-buty 1 phosphonoxy)methoxy]butane, IV, (17 g) was dissolved in CH C1 (100 mL). To this solution was added TFA (50 mL) and the reaction mixture was stirred at rt for 0.25 h. The reaction mixture was then concentrated under reduced pressure. To the residue was added H₂O (200 mL), Et₂O (100 mL) and EtOAc (100 mL). The pH of the aqueous layer was adjusted to 7.6 by addition of solid Na₂CO₃ and then the organic and aqueous layers were separated. The aqueous layer was then subjected to reverse phase chromatography on 400 g of C-18 eluted with H₂O to 5% CH₃CN/Η₂O. The product containing fractions were concentrated under reduced pressure, frozen and lyophilized to afford 1.5 g of the subtitled compound, I, as a white solid. (1.5 g, 12% over two steps). Η NMR (500 MHz, D₂O) δ 8.91 (s, IH), 7.92 (s, IH), 7.81 (d, 2H, J=8), 7.80 (s, IH), 7.77 (d, 2H, J=8), 7.21 (dd, IH, J=15,9), 6.99 (ddd, IH, J=9,9,2), 6.91 (ddd, IH, J=9,9,2), 5.35 (dd, IH, J=6,6), 5.29 (d, IH, J=15), 5.21 (dd, IH, J=6,6), 5.19 (d, IH, J=15), 3.86 (q, IH, J=7), and 1.35 (d, 3H, J=7); MS [(ESI^" (M-HV 546.1]; Anal. Calcd for C23Hi8F₂N5θ5SιPι Na2/3.5 H₂O: C, 42.21 : H, 3.85: N, 10.70: Na, 7.03. Found: C, 42.32: H, 3.83: N, 10.60: Na, 7.04.

 

 

Di-tert-butyl chloromethyl phosphate, III:

Di-tert-butyl chloromethyl phosphate, III, may be made by any of the following methods.

Method 1

Silver di-t-butyl phosphate (6.34 g, 20 mmol), which was prepared by mixing di- t-butyl phosphate (obtained from di-t-butyl phosphite by the method of Zwierzak and Kluba, Tetrahedron, 1971 , 27, 3163) with one equivalent of silver carbonate in 50% aqueous acetonitrile and by lyophilizing to dryness, was placed together with chloroiodomethane (35 g, 200 mmol) in benzene and stirred at room temperature for 18 hrs. The reaction mixture was filtered and the filtrate concentrated under reduced pressure. The residue was chromatographed on silica and eluted with 2:1 hexanes-ethyl acetate. Appropriate fractions were concentrated to dryness to obtain the subtitled compound III (3.7 g, 71% yield): H NMR (CDCI3) δ 5.63 (d, 2H, J=17), 1.51 (s, 18H); MS (MH⁺ = 259).

Method 2

Tetrabutylammonium di-t-butyl phosphate was prepared by dissolving di-t-butyl phosphate [ 20g, 94 mmol (obtained from di-t-butyl phosphite by the method of Zwierzak and Kluba, Tetrahedron, 1971, 27, 3163)] in methanolic tetrabutylammonium hydroxide (47 mL of 1M solution, 47 mmol). The reaction mixture had a temperature of 23 °C and pH of 4.33. The pH of the reaction mixture was adjusted to 6.5-7.0 by addition of methanolic tetrabutylammonium hydroxide (48 mL of 1M solution, 48 mmol) over 0.2 h. The reaction mixture was stirred for 0.5 h at approximately 26 °C and then was concentrated under reduced pressure at a bath temperature below 40 °C. The crude residue was azeotroped three times by adding toluene (3×100 mL) and then the mixture was concentrated under reduced pressure. The crude residue was then triturated in cold hexanes (0°C) for 1 h and then the solid was collected by filtration, washed with a minimum amount of cold hexanes and dried to give a first crop of tetrabutylammonium di-t-butyl phosphate as a white solid. (24. Og). The mother liquor was concentrated under reduced pressure and then triturated in cold hexanes (20 mL) for 1 h. The solid was collected by filtration, washed with a minimum amount of cold hexanes and dried to give a second crop of tetrabutylammonium di-t-butyl phosphate as a white solid. [(8.5g), 32.5g total (77%)]. A solution of tetrabutylammonium di-t-butyl phosphate (218 g, 480 mmol) in benzene (200 mL) was added dropwise to stirred chloroiodomethane (800g, 4535 mmol) over 1.5 h at rt. The reaction mixture was stirred an additional 1.5 h at rt and then was concentrated under reduced pressure. The oily residue was dissolved in Et₂O and filtered to remove white solids which had precipitated. The organic layer was washed with saturated NaHCO₃ and H O/brine (1/1). The organic layer was then dried over magnesium sulfate, filtered and concentrated under reduced pressure to yield a red brown oil (320 g). The red brown oil was subjected to chromatography on silica gel (800g) eluted with 20% EtOAc/Hexanes, 25% EtOAc/Hexanes then 30% EtOAc/Hexanes. The product containing fractions were concentrated under reduced pressure to yield a golden oil. The oil was diluted with CH₂C1₂ (30 mL) , concentrated under reduced pressure and then dried under vacuum to yield the subtitled compound III (61.3g, 49% yield). 1H NMR (Benzene-d₆) δ 5.20 (2H, d, J=15), 1.22 (18H, s).

Method 3

Iodochloromethane (974 g, 402 mL, 5.53 mol) at 25°C was treated with tetrabutylammonium di-t-butylphosphate (250 g, 0.553 mol). The phosphate was added portion wise over 10 minutes. The heterogeneous mixture became a clear pink solution after approximately 15 minutes. The mixture was stirred for three hours, and the iodochloromethane was then removed by rotary evaporation with a bath temperature of <30°C. The residue was taken up in 1 L t-butyl methyl ether and stirred for 15 minutes to precipitate tetrabutylammonium iodide by-product. Tetrabutylammonium iodide was removed by vacuum filtration through a sintered glass funnel. The filtrate was concentrated by rotary evaporation to an oil which contained a 5:1 mixture of III and undesired dimer impurity

III”

The mixture can be purified by a silica gel chromatography to obtain III as pure compound in ~60% yield as an oil.

EXAMPLE 2

(2R,3R)-3-[4-(4-cyanophenyl)thiazol-2-yl]-2-(2,4-difluorophenyl)-l-(lH-l,2,4- triazol- 1 -yl)-2- (dihydrogen phosphonoxy)methoxy]butane

A. An oven dried, 1L round-bottom flask equipped with a mechanical stirrer, nitrogen inlet adapter, pressure-equalizing addition funnel fitted with a rubber septum and temperature probe was charged with sodium hydride (2.89 g, 0.069 mol, 60%) and THF (50 mL). To this stirred suspension, (2R,3R)-3-[4-(4- cyanophenyl)thiazol-2-yl]-2-(2,4-difluorophenyl)- 1 -( 1 H- 1 ,2,4-triazol- 1 -yl)butan- 2-ol, II, (10 g, 0.023 mol) in 30 mL of THF was added dropwise over 20 minutes at room temperature. After stirring for 45 minutes, a solution of iodine (2.99 g, 0.0115 mol) in THF (30 mL)) was added dropwise over 10 minutes followed by dropwise addition of compound di tert butylchloromethyl phosphate, III (13.29 g, 0.035 mol, -68% purity) over 15 minutes. The reaction mixture was stirred for 4 hours at about 41 °C to complete the reaction. The completion of the reaction was judged by in-process HPLC. The reaction mixture was poured into ice cold water (100 mL). The aqueous phase was separated and extracted with ethyl acetate (3 x 50 mL) and the combined organic extract was washed with 10% sodium thiosulfite (50 mL), water (50 mL), brine (50 mL), dried over magnesium sulfate and concentrated under reduced pressure to give pale yellow oil (22.8 g, In-process HPLC: ~ 97% pure). The crude product was used “as is” in step B.

B. To a round-bottom flask equipped with magnetic stirrer, cooling bath, pH probe and N₂ inlet-outlet was charged the product of Step A above (7.5 g) in CH₂C1₂ (23 mL) and cooled to 0 °C. To this stirred solution, trifluoroacetic acid (8.8 mL) was added slowly and stirred for 3 h to complete the reaction. The completion of the reaction was judged by in-process HPLC. The reaction mixture was poured into a cold solution of 2N NaOH (64 mL). The reaction mixture was extracted with t-butyl acetate (2 x 65 mL) to remove all the organic impurities. The aqueous layer containing the title product as bis sodium salt was treated with activated charcoal (10 g) and filtered through a bed of Celite. The clear filtrate was acidified with IN HC1 to pH 2.5. The free acid, the title product, was extracted into ethyl acetate (2 x 50 mL). The combined organic layer was washed with water, dried over MgSO₄₎ filtered, and the filtrate concentrated under reduced pressure to afford 3.39 g of crude title product.

EXAMPLE 3

Bis lysine salt of (2R,3R)-3-r4-(4-cyanophenyl)thiazol-2-yl]-2-(2,4- difluorophenyl)- 1 -( 1 H- 1 ,2,4-triazol- 1 -yl)-2-[(dihydrogen phosphonoxy)methoxy]butane

The above obtained title product from Example 2 was dissolved in methanol (75 mL) and to this L-lysine (1.8 g) was added and heated at 60 °C for 4.5 h. The hot reaction mixture was filtered through a bed of Celite. The filtrate was concentrated to about 5 mL, mixed with ethanol (100 mL) and heated to 65 °C to crystallize the bis lysine salt. The salt was collected on a Buchner funnel and dried under vacuum to afford 3.71 g of the title compound as an off white crystalline solid.

About Eisai Co., Ltd.
Eisai Co., Ltd. is a research-based human health care (hhc) company that discovers, develops, and markets products throughout the world. Eisai focuses its efforts in three therapeutic areas: integrative neuroscience, including neurology and psychiatric medicines; integrative oncology, which encompasses oncotherapy and supportive-care treatments; and vascular and immunological reactions. Eisai contributes to the well-being of people around the world through a global network of research facilities, manufacturing sites and marketing subsidiaries. For more information about Eisai Co., Ltd., please visit http://www.eisai.co.jp/index-e.html.

ref

BMS-379224, a water-soluble prodrug of ravuconazole
42nd Intersci Conf Antimicrob Agents Chemother (ICAAC) (September 27-30, San Diego) 2002, Abst F-817

some animations

Tioconazole;UK-20349;Trosyd;Trosyl;Vagistat-1

l-[2-(2-chloro-3-thienyl)methoxy]-2-(2,4- dichlorophenyl)ethyl]-lH-imidazole,

1-[2-(2-Chloro-3-thienylmethoxy)-2-(2,4-dichlorophenyl)ethyl]-1H-imidazole

65899-73-2

Launched – 1983, Bristol-Myers Squibb

Tioconazole is an antifungal medication of the imidazole class used to treat infections caused by a fungus or yeast. It is marketed under the brand names Trosyd and Gyno-Trosyd (Pfizer). Tioconazole ointments serve to treat women’s vaginal yeast infections.^[1]They are available in one day doses, as opposed to the 7-day treatments more common in use in the past.

Tioconazole topical (skin) preparations are also available for ringworm, jock itch, athlete’s foot, and tinea versicolor or “sun fungus”.

Side effects

Side effects (for the women’s formulas) may include temporary burning/irritation of the vaginal area, moderate drowsiness, headachesimilar to a sinus headache, hives, and upper respiratory infection. These side effects may be only temporary, and do not normally interfere with the patient’s comfort enough to outweigh the end result.

Tioconazole

Systematic (IUPAC) name
(RS)-1-[2-[(2-Chloro-3-thienyl)methoxy]-2-(2,4-dichlorophenyl)ethyl]-1H-imidazole
Clinical data
Trade names	Vagistat-1
AHFS/Drugs.com	monograph
Legal status	US: OTC
Routes	Topical
Identifiers
CAS number	65899-73-2
ATC code	D01AC07 G01AF08
PubChem	CID 5482
DrugBank	DB01007
KEGG	D00890
Synonyms	Thioconazole
Chemical data
Formula	C16H13Cl3N2OS
Mol. mass	387.711 g/mol

http://www.google.com/patents/EP0934279A1?cl=en

Imidazole derivatives, in particular, l-[2-(2-chloro-3-thienyl)methoxy]-2-(2,4- dichlorophenyl)ethyl]-lH-imidazole, commonly referred to as tioconazole, are known for their antifungal therapeutic properties. US 4,062,966 discloses a process for the preparation of l-aryl-2-(l -imidazolyl) alkyl ethers and thioethers which employs arylation of an appropriate 1 -aryl-2-(l -imidazolyl)alkanol or alkane thiol having the formula

wherein R^l to R⁴ are each H or C,^ alkyl, Ar is phenyl, or substituted phenyl wherein said substitutents are halogen, C,^ alkyl, C,_₆ alkoxy, thienyl, or halothienyl, and, Z is oxygen or sulfur. In accordance with US’966, the reaction comprises converting the alcohol or thiol in a suitable solvent to its alkali metal derivative by treatment with a strong base, such as an alkali metal amide or hydride, and reacting with the appropriate aralkyl halide ofthe formula

X-(CH₂)η-Y

where n is 1 or 2, Y is an aromatic heterocyclic group or substituted heterocyclic group, wherein substitutents are halogen, C,.₆ alkyl, or C,.₆ alkoxy atoms, thienyl or halothienyl group, and X is a halogen, preferably chlorine. Tetrahydrofuran (THF) is the preferred solvent taught in US ‘966. Reaction temperatures may range from about 0 °C to reflux temperature ofthe solvent and reaction times range from about 1 hour to about 24 hours. The product is isolated with water, extracted with ether, and may be purified as the free base or converted to a salt, e.g. the hydrochloride, and purified by recrystallization. A disadvantage ofthe process disclosed in US ‘966 is that THF is a peroxide generator which presents the potential for an explosion. From a commercial viewpoint, peroxide generators are not preferred due to the dangers associated therewith.

GB 1 522 848 discloses a process for the preparation of imidazoles useful as antifungal agents involving a labor intensive, multi-sequence reaction of an imidazole ether with a reactive ester. Like US ‘966, THF is employed presenting similar concerns in the synthesis ofthe desired imidazole product.

According to the Pharmaceutical Manufacturing Encyclopedia, tioconazole is prepared by dissolving l-(2,4-dichlorophenyl)-2-(l- imidazolyl)ethanol in THF and sodium hydride and heating to about 70 ^βC. The resulting mixture is then contacted with 2-chloro-3- chloromethylthiophene and heated to reflux (about 67 ^CC). The resulting product is filtered, saturated with hydrogen chloride, triturated and recrystallized to obtain the purified tioconazole hydrochloride product having a melting point of about 170 ^βC. This salt must then be freebased to form the product used in pharmaceutical formulations. This route, like those discussed above, also presents the dangers of a potential explosion. There is thus a continuing need for a commercially viable, synthetic route for the production of imidazoles, in particular tioconazole.

…………………….

see   US 4062966

http://www.google.com/patents/US4062966

………………………….

References

Duvelisib

Infinity and AbbVie partner to develop and commercialise duvelisib for cancer

INK 1197; IPI 145; 8-Chloro-2-phenyl-3-[(1S)-1-(9H-purin-6-ylamino)ethyl]-1(2H)-isoquinolinone

1(2H)-Isoquinolinone, 8-chloro-2-phenyl-3-((1S)-1-(9H-purin-6-ylamino)ethyl)-
8-Chloro-2-phenyl-3-((1S)-1-(7H-purin-6-ylamino)ethyl)isoquinolin-1(2H)-one

(S)-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

UNII-610V23S0JI; IPI-145; INK-1197;

Originator…….. Millennium Pharmaceuticals

 
Infinity Pharmaceuticals has partnered with AbbVie to develop and commercialise its duvelisib (IPI-145), an oral inhibitor of phosphoinositide-3-kinase (PI3K)-delta and PI3K-gamma, to treat patients with cancer. 

Infinity Pharmaceuticals has partnered with AbbVie to develop and commercialise its duvelisib (IPI-145), an oral inhibitor of phosphoinositide-3-kinase (PI3K)-delta and PI3K gamma, to treat patients with cancer.

Duvelisib has shown clinical activity against different blood cancers, such as indolent non-Hodgkin’s lymphoma (iNHL) and chronic lymphocytic leukemia (CLL).

AbbVie executive vice-president and chief scientific officer Michael Severino said: “We believe that duvelisib is a very promising investigational treatment based on clinical data showing activity in a broad range of blood cancers.”

http://www.pharmaceutical-technology.com/news/newsinfinity-abbvie-partner-develop-commercialise-duvelisib-cancer-4363381?WT.mc_id=DN_News 

Duvelisib (IPI-145,  INK-1197), an inhibitor of PI3K-delta and –gamma, originated at Takeda subsidiary Intellikine. It is now being developed by Infinity Pharmaceuticals, which began a phase III trial in November, following US and EU grant of orphan drug status for both CLL and small lymphocytic leukemia

INK-1197 is a dual phosphatidylinositol 3-Kinase delta (PI3Kdelta) and gamma (PI3Kgamma) inhibitor in phase III clinical development at Infinity Pharmaceuticals for the treatment of chronic lymphocytic leukemia and small lymphocytic lymphoma. The company is also carring phase II trials for the treatment of patients with mild asthma undergoing allergen challenge, for the treatment of rheumatoid arthritis and for the treatment of refractory indolent non-Hodgkin’s lymphoma. Phase I clinical trials for the treatment of advanced hematological malignancies (including T-cell lymphoma and mantle cell lymphoma) are currently under way.
IPI-145 is an oral inhibitor of phosphoinositide-3-kinase (PI3K)-delta and PI3K-gamma. The PI3K-delta and PI3K-gamma isoforms are preferentially expressed in leukocytes (white blood cells), where they have distinct and non-overlapping roles in key cellular functions, including cell proliferation, cell differentiation, cell migration and immunity. Targeting PI3K-delta and PI3K-gamma may provide multiple opportunities to develop differentiated therapies for the treatment of blood cancers and inflammatory diseases.
Licensee Infinity Pharmaceuticals is developing INK-1197. In 2014, Infinity licensed Abbvie for joint commercialization in the U.S. and exclusive commercialization elsewhere. Originator Millennium Pharmaceuticals had also been developing the compound; however, no recent development has been reported for this research. In 2013, orphan drug designations were assigned by the FDA and the EMA for the treatment of chronic lymphocytic leukemia, for the treatment of small lymphocytic lymphoma and for the treatment of follicular lymphoma.

currently enrolling patients DYNAMO™, a Phase 2 study designed to evaluate the activity and safety of IPI-145 in approximately 120 people with refractory indolent non-Hodgkin lymphoma (iNHL) and DUO™, a Phase 3 clinical study of IPI-145 in approximately 300 people with relapsed/refractory chronic lymphocytic leukemia (CLL). These studies are supported by Phase 1 data reported at the 2013 American Society of Hematology (ASH) Annual Meeting which showed that IPI-145 was well tolerated and clinically active in a broad range of malignancies, including iNHL and CLL. These studies are part of DUETTS™, a worldwide investigation of IPI-145 in blood cancers.

WO 2011008302

http://www.google.com/patents/WO2011008302A1?cl=en

Reaction Scheme 1

Reaction Scheme 2:

201 202 203

204 205

Reaction Scheme 3:

Reaction Scheme 4A:

Reaction Scheme 4B:

2

Example 14b: Synthesis of (S)-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (9)

(compound 4904)

Scheme 27b. The synthesis of (S)-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (9)

(compound 4904) is described.

[00493] The compound of Formula 4904 (compound 292 in Table 4) was synthesized using the synthetic transformations as described in Examples 12 and 14a, but 2-chloro-6-methyl benzoic acid (compound 4903) was used instead of 2, 6 ,dimethyl benzoic acid (compound 4403). By a similar method, compound 328 in Table 4 was synthesized using the synthetic transformations as described starting from the 2-chloro-6-methyl m-fluorobenzoic acid.

 

…………………………………….

http://www.google.com/patents/WO2012097000A1?cl=en  OR   http://www.google.com/patents/US8809349?cl=en

Formula (I):

(I),

or a pharmaceutically acceptable salt, solvate, or hydrate thereof. In one embodiment, the method comprises any one, two, three, four, five, six, seven, or eight, or more of the following steps:

“Formula (I)” includes (S)-3-(l -(9H-purin-6-ylamino)ethyl)-8-chloro-2- phenylisoquinolin-l(2H)-one in its imide tautomer shown below as (1-1) and in its lactim tautomer shown below as (1-2):

(1-1)………………………………………………………………………………… (1-2)

[0055] FIG. 27 shows an FT-IR spectra of Polymorph Form C.

 

 

[0056] FIG. 28 shows a ‘H-NMR spectra of Polymorph Form C.

 

 

[0057] FIG. 29 shows a ¹³C-NMR spectra of Polymorph Form C.

 

Example 1

Synthesis of (S)-3-(l-aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

Example 1A

1 2

[00563] Compound 1 (6.00 kg) was treated with 1-hydroxybenzotriazole monohydrate (HOBt^»H₂0), triethylamine, Ν,Ο-dimethylhydroxylamine hydrochloride, and EDCI in dimethylacetamide (DMA) at

10 °C. The reaction was monitored by proton NMR and deemed complete after 2.6 hours, affording Compound 2 as a white solid in 95% yield. The R-enantiomer was not detected by proton NMR using (R)-(- ) -alpha-ace tylmandelic acid as a chiral-shift reagent.

[00564] Compound 3 (4.60 kg) was treated with p-toluenesulfonic acid monohydrate and 3,4-dihydro-2H- pyran (DHP) in ethyl acetate at 75 °C for 2.6 hours. The reaction was monitored by HPLC. Upon completion of the reaction, Compound 4 was obtained as a yellow solid in 80% yield with >99% (AUC) purity by HPLC analysis.

[00565] Compound 5 (3.30 kg) was treated with thionyl chloride and a catalytic amount of DMF in methylene chloride at 25 °C for five hours. The reaction was monitored by HPLC which indicated a 97.5% (AUC) conversion to compound 6. Compound 6 was treated in situ with aniline in methylene chloride at 25 °C for 15 hours. The reaction was monitored by HPLC and afforded Compound 7 as a brown solid in 81% yield with >99% (AUC) purity by HPLC analysis. [00566] Compound 2 was treated with 2.0 M isopropyl Grignard in THF at -20 °C. The resulting solution was added to Compound 7 (3.30 kg) pre -treated with 2.3 M n-hexyl lithium in tetrahydrofuran at -15 °C. The reaction was monitored by HPLC until a 99% (AUC) conversion to Compound 8 was observed.

Compound 8 was treated in situ with concentrated HC1 in isopropyl alcohol at 70 °C for eight hours. The reaction was monitored by HPLC and afforded Compound 9 as a brown solid in 85% yield with 98% (AUC) purity and 84% (AUC) ee by HPLC analysis.

Example ID

[00567] Compound 9 (3.40 kg) was treated with D-tartaric acid in methanol at 55 °C for 1-2 hours. The batch was filtered and treated with ammonium hydroxide in deionized (DI) water to afford enantiomerically enriched Compound 9 as a tan solid in 71% yield with >99% (AUC) purity and 91% (AUC) ee by HPLC analysis.

Example 2

Synthesis of (S)-3-(l-aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

Example 2A

[00568] To Compound 7 (20.1 g) was charged 100 mL of anhydrous THF. The resulting solution was cooled to about -10 °C and 80 mL of n-hexyl lithium (2.3 M in hexanes, 2.26 equiv.) was slowly added (e.g. , over about 20 min). The resulting solution was stirred at about -10 °C for about 20 min.

[00569] To Compound 2 (26.5 g; 1.39 equiv.) was charged 120 mL of anhydrous THF. The resulting mixture was cooled to about -10 °C and 60 mL of isopropyl magnesium chloride (2.0 M in THF, 1.47 equiv.) was slowly added (e.g. , over about 15-20 min). The resulting mixture was then stirred at about -10 °C for about 20 min. The mixture prepared from Compound 2 was added to the solution prepared from Compound 7 while maintaining the internal temperature between about -10 and about 0 °C. After the addition was complete (about 5 min), the cold bath was removed, and the resulting mixture was stirred at ambient temperature for about 1 h, then cooled. [00570] A solution of 100 mL of anisole and 33 mL of isobutyric acid (4.37 equiv.) was prepared. The anisole solution was cooled to an internal temperature of about -3 °C. The above reaction mixture was added to the anisole solution such that the internal temperature of the anisole solution was maintained at below about 5 °C. The ice bath was then removed (after about 15 min, the internal temperature was about 7 °C). To the mixture, 100 mL of 10 wt aqueous NaCl solution was rapidly added (the internal temperature increased from about 7 °C to about 15 °C). After stirring for about 30 min, the two phases were separated. The organic phase was washed with another 100 mL of 10 wt aqueous NaCl. The organic phase was transferred to a flask using 25 mL of anisole to facilitate the transfer. The anisole solution was then concentrated to 109 g. Then, 100 mL of anisole was added.

[00571] To the approximately 200 mL of anisole solution was added 50 mL of TFA (8 equiv.) while maintaining the internal temperature below about 45-50 °C. The resulting solution warmed to about 45-50 °C and stirred for about 15 hrs, then cooled to 20-25 °C. To this solution was added 300 mL of MTBE dropwise and then the resulting mixture was held at 20-25 °C for 1 h. The mixture was filtered, and the wet cake washed with approximately 50 mL of MTBE. The wet cake was conditioned on the filter for about 1 h under nitrogen. The wet cake was periodically mixed and re-smoothed during conditioning. The wet cake was then washed with 200 mL of MTBE. The wet cake was further conditioned for about 2 h (the wet cake was mixed and resmoothed after about 1.5 h). The wet cake was dried in a vacuum oven at about 40 °C for about 18 h to afford Compound 9^»TFA salt in about 97.3% purity (AUC), which had about 99.1 % S- enantiomer (e.g. , chiral purity of about 99.1 %).

[00572] Compound 9^»TFA salt (3 g) was suspended in 30 mL of EtOAc at about 20 °C. To the EtOAc suspension was added 4.5 mL (2.2 eq.) of a 14% aqueous ammonium hydroxide solution and the internal temperature decreased to about 17 °C. Water (5 mL) was added to the biphasic mixture. The biphasic mixture was stirred for 30 min. The mixing was stopped and the phases were allowed to separate. The aqueous phase was removed. To the organic phase (combined with 5 mL of EtOAc) was added 10 mL of 10% aqueous NaCl. The biphasic mixture was stirred for about 30 min. The aqueous phase was removed. The organic layer was concentrated to 9 g. To this EtOAc mixture was added 20 mL of i-PrOAc. The resulting mixture was concentrated to 14.8 g. With stirring, 10 mL of n-heptane was added dropwise. The suspension was stirred for about 30 min, then an additional 10 mL of n-heptane was added. The resulting suspension was stirred for 1 h. The suspension was filtered and the wet cake was washed with additional heptane. The wet cake was conditioned for 20 min under nitrogen, then dried in a vacuum oven at about 40 °C to afford Compound 9 free base in about 99.3% purity (AUC), which had about 99.2% S-enantiomer (e.g., chiral purity of about 99.2%).

Example 2B [00573] A mixture of Compound 7 (100 g, 0.407 mol, 1 wt) and THF (500 mL, 5 vol) was prepared and cooled to about 3 °C. n-Hexyllithium (2.3 M in hexanes, 400 mL, 0.920 mol, 2.26 equiv) was charged over about 110 minutes while maintaining the temperature below about 6 °C. The resulting solution was stirred at 0 ± 5 °C for about 30 minutes. Concurrently, a mixture of Compound 2 (126 g, 0.541 mol, 1.33 equiv) and THF (575 mL, 5.8 vol) was prepared. The resulting slurry was charged with isopropylmagnesium chloride (2.0 M in THF, 290 mL, 0.574 mol, 1.41 equiv) over about 85 minutes while maintaining the temperature below about 5 °C. The resulting mixture was stirred for about 35 minutes at 0 ± 5 °C. The Compound 2 magnesium salt mixture was transferred to the Compound 7 lithium salt mixture over about 1 hour while maintaining a temperature of 0 ± 5 °C. The solution was stirred for about 6 minutes upon completion of the transfer.

[00574] The solution was added to an about -5 °C stirring solution of isobutyric acid (165 mL, 1.78 mol, 4.37 equiv) in anisole (500 mL, 5 vol) over about 20 minutes during which time the temperature did not exceed about 6 °C. The resulting solution was stirred for about 40 minutes while being warmed to about 14 °C. Then, a 10% sodium chloride solution (500 mL, 5 vol) was rapidly added to the reaction. The temperature rose to about 21 °C. After agitating the mixture for about 6 minutes, the stirring was ceased and the lower aqueous layer was removed (about 700 mL). A second portion of 10% sodium chloride solution (500 mL, 5 vol) was added and the mixture was stirred for 5 minutes. Then, the stirring was ceased and the lower aqueous layer was removed. The volume of the organic layer was reduced by vacuum distillation to about 750 mL (7.5 vol).

[00575] Trifluoroacetic acid (250 mL, 3.26 mol, 8.0 equiv) was added and the resulting mixture was agitated at about 45 °C for about 15 hours. The mixture was cooled to about 35 °C and MTBE (1.5 L, 15 vol) was added over about 70 minutes. Upon completion of the addition, the mixture was agitated for about 45 minutes at about 25-30 °C. The solids were collected by vacuum filtration and conditioned under N₂ for about 20 hours to afford Compound 9*TFA salt in about 97.5% purity (AUC), which had a chiral purity of about 99.3%.

[00576] Compound 9^»TFA salt (100 g) was suspended EtOAc (1 L,10 vol) and 14% aqueous ammonia (250 mL, 2.5 vol). The mixture was agitated for about 30 minutes, then the lower aqueous layer was removed. A second portion of 14% aqueous ammonia (250 mL, 2.5 vol) was added to the organic layer. The mixture was stirred for 30 minutes, then the lower aqueous layer was removed. Isopropyl acetate (300 mL, 3 vol) was added, and the mixture was distilled under vacuum to 500 mL (5 vol) while periodically adding in additional isopropyl acetate (1 L, 10 vol).

[00577] Then, after vacuum-distilling to a volume of 600 mL (6 vol), heptanes (1.5 L, 15 vol) were added over about 110 minutes while maintaining a temperature between about 20 °C and about 30 °C. The resulting slurry was stirred for about 1 hour, then the solid was collected by vacuum filtration. The cake was washed with heptanes (330 mL, 3.3 vol) and conditioned for about 1 hour. The solid was dried in an about 45 °C vacuum oven for about 20 hours to afford Compound 9 free base in about 99.23% purity (AUC), which has a chiral purity of about 99.4%.

Example 3

Chiral Resolution of (S)-3-(l-aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (Compound 9)

[00578] In some instances, (S)-3-(l-aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (Compound 9) obtained by synthesis contained a minor amount of the corresponding (R)-isomer. Chiral resolution procedures were utilized to improve the enantiomeric purity of certain samples of (S)-3-(l-aminoethyl)-8- chloro-2-phenylisoquinolin- 1 (2H)-one.

[00579] In one experiment, Compound 9 (3.40 kg) was treated with D-tartaric acid in methanol at about 55 °C for about 1 to about 2 hours. The mixture was filtered and treated with ammonium hydroxide in deionized (DI) water to afford Compound 9 in greater than about 99% (AUC) purity, which had a chiral purity of about 91% (AUC).

[00580] In another procedure, MeOH (10 vol.) and Compound 9 (1 equiv.) were stirred at 55 ± 5 °C. D- Tartaric acid (0.95 equiv.) was charged. The mixture was held at 55 ± 5 °C for about 30 min and then cooled to about 20 to about 25 °C over about 3 h. The mixture was held for about 30 min and then filtered. The filter cake was washed with MeOH (2.5 vol.) and then conditioned. The cake was returned to the reactor and water (16 vol.) was charged. The mixture was stirred at 25 ± 5 °C. NH₄OH was then charged over about 1 h adjusting the pH to about 8 to about 9. The mixture was then filtered and the cake was washed with water (4 vol.) and then heptanes (4 vol.). The cake was conditioned and then vacuum dried at 45-50 °C to afford Compound 9 free base with a chiral purity of about 99.0%.

Example 4

Synthesis of (S)-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

[00581] A mixture of Compound 7 (1 equiv.) and anhydrous THF (5 vol.) was prepared. Separately, a mixture of Compound 2 (1.3 equiv.) and anhydrous THF (5 vol.) was prepared. Both mixtures were stirred for about 15 min at about 20 to about 25 °C and then cooled to -25 ± 15 °C. n-Hexyl lithium (2.05 equiv.) was added to the Compound 7 mixture, maintaining the temperature at > 5 °C. i-PrMgCl (1.33 equiv.) was added to the Compound 2 mixture, maintaining the temperature at > 5 °C. The Compound 2 mixture was transferred to the Compound 7 mixture under anhydrous conditions at 0 ± 5 °C. The resulting mixture was warmed to 20 ± 2 °C and held for about 1 h. Then, the reaction was cooled to -5 ± 5 °C, and 6 N HC1 (3.5 equiv.) was added to quench the reaction, maintaining temperature at below about 25 °C. The aqueous layer was drained, and the organic layer was distilled under reduced pressure until the volume was 2-3 volumes. IPA (3 vol.) was added and vacuum distillation was continued until the volume was 2-3 volumes. IPA (8 vol.) was added and the mixture temperature was adjusted to about 60 °C to about 75 °C. Cone. HC1 (1.5 vol.) was added and the mixture was subsequently held for 4 hours. The mixture was distilled under reduced pressure until the volume was 2.5-3.5 volumes. The mixture temperature was adjusted to 30 ± 10 °C. DI water (3 vol.) and DCM (7 vol.) were respectively added to the mixture. Then, NH₄OH was added to the mixture, adjusting the pH to about 7.5 to about 9. The temperature was adjusted to about 20 to about 25 °C. The layers were separated and the aqueous layer was washed with DCM (0.3 vol.). The combined DCM layers were distilled until the volume was 2 volumes. i-PrOAc (3 vol.) was added and vacuum distillation was continued until the volume was 3 volumes. The temperature was adjusted to about 15 to about 30 °C. Heptane (12 vol.) was charged to the organic layer, and the mixture was held for 30 min. The mixture was filtered and filter cake was washed with heptane (3 vol.). The cake was vacuum dried at about 45 °C afford Compound 9.

[00582] Then, MeOH (10 vol.) and Compound 9 (1 equiv.) were combined and stirred while the temperature was adjusted to 55 ± 5 °C. D-Tartaric acid (0.95 equiv.) was charged. The mixture was held at 55 ± 5 °C for about 30 min and then cooled to about 20 to about 25 °C over about 3 h. The mixture was held for 30 min and then filtered. The filter cake was washed with MeOH (2.5 vol.) and then conditioned. Water (16 vol.) was added to the cake and the mixture was stirred at 25 ± 5 °C. NH₄OH was charged over 1 h adjusting the pH to about 8 to about 9. The mixture was then filtered and the resulting cake washed with water (4 vol.) and then heptanes (4 vol.). The cake was conditioned and then vacuum dried at 45-50 °C to afford Compound 9.

[00583] To a mixture of i-PrOH (4 vol.) and Compound 9 (1 equiv.) was added Compound 4 (1.8 equiv.), Et₃N (2.5 equiv.) and i-PrOH (4 vol.). The mixture was agitated and the temperature was adjusted to 82 ± 5 °C. The mixture was held for 24 h. Then the mixture was cooled to about 20 to about 25 °C over about 2 h. The mixture was filtered and the cake was washed with i-PrOH (2 vol.), DI water (25 vol.) and n-heptane (2 vol.) respectively. The cake was conditioned and then vacuum dried at 50 ± 5 °C to afford Compound 10.

To a mixture of EtOH (2.5 vol.) and Compound 10 (1 equiv.) was added EtOH (2.5 vol.) and DI water (2 vol.). The mixture was agitated at about 20 to about 25 °C. Cone. HC1 (3.5 equiv.) was added and the temperature was adjusted to 35 ± 5 °C. The mixture was held for about 1.5 h. The mixture was cooled to 25 ± 5 °C and then polish filtered to a particulate free vessel. NH₄OH was added, adjusting the pH to about 8 to about 9. Crystal seeds of Form C of a compound of Formula (I) (0.3 wt ) were added to the mixture which was held for 30 minutes. DI water (13 vol.) was added over about 2 h. The mixture was held for 1 h and then filtered. The resulting cake was washed with DI water (4 vol.) and n-heptane (2 vol.) respectively. The cake was conditioned for about 24 h and then DCM (5 vol.) was added. This mixture was agitated for about 12 h at about 20 to about 25 °C. The mixture was filtered and the cake washed with DCM (1 vol.). The cake was conditioned for about 6 h. The cake was then vacuum-dried at 50 ± 5 °C. To the cake was added DI water (10 vol.), and i-PrOH (0.8 vol.) and the mixture was agitated at 25 ± 5 °C for about 6 h. An XRPD sample confirmed the compound of Formula (I) was Form C. The mixture was filtered and the cake was washed with DI water (5 vol.) followed by n-heptane (3 vol.). The cake was conditioned and then vacuum dried at 50 ± 5 °C to afford a compound of Formula (I) as polymorph Form C. Example 5

Synthesis of (S)-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

Example 5A

[00584] Compound 9 (2.39 kg) was treated with Compound 4 and triethylamine in isopropyl alcohol at 80 °C for 24 hours. The reaction was monitored by HPLC until completion, affording 8-chloro-2-phenyl-3- ((lS)-l-(9-(tetrahydro-2H^yran-2-yl)-9H^urin-6-ylamino)ethyl)isoquinolin-l(2H)-one (compound 10) as a tan solid in 94% yield with 98% (AUC) purity by HPLC analysis.

[00585] 8-Chloro-2-phenyl-3-((lS)-l-(9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-ylamino)ethyl)- isoquinolin-l(2H)-one (compound 10) (3.63 kg) was treated with HC1 in ethanol at 30 °C for 2.3 hours. The reaction was monitored by HPLC until completion, and afforded a compound of Formula (I) as a tan solid in 92% yield with >99% (AUC) purity and 90.9% (AUC) ee by HPLC analysis.

Example 5B

[00586] 3-(l-Aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (Compound 9) (0.72 mmol), 6-chloro- 9-(tetrahydro-2H-pyran-2-yl)-9H-purine (Compound 4) (344 mg, 1.44 mmol) and DIPEA

(279 mg, 2.16 mmol) were dissolved in «-BuOH (20 mL), and the resulting mixture was stirred at reflux for 16 h. The reaction mixture was concentrated in vacuo and purified by flash column chromatography on silica gel (eluting with 30% to 50% Hex/EA) to afford the product, 8-chloro-2-phenyl-3-((lS)-l-(9-(tetrahydro-2H- pyran-2-yl)-9H-purin-6-ylamino)ethyl)isoquinolin-l(2H)-one (Compound 10), as a white solid (60% yield). [00587] 8-Chloro-2-phenyl-3-((lS)-l-(9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-ylamino)ethyl)- isoquinolin-l(2H)-one (Compound 10) (0.42 mmol) was dissolved in HCl/EtOH (3 M, 5 mL), and the resulting mixture was stirred at room temperature for 1 h. The reaction mixture was quenched with saturated NaHC0₃ aqueous solution and the pH was adjusted to about 7-8. The mixture was extracted with CH₂C1₂ (50 mL x 3), dried over anhydrous Na₂S0₄, and filtered. The filtrate was concentrated in vacuo, and the residue was recrystallized from ethyl acetate and hexanes (1 : 1). The solid was collected by filtration and dried in vacuo to afford the product (S)-3-(l-(9H-purin-6-ylamino) ethyl)-8-chloro-2-phenylisoquinolin- l(2H)-one (Formula (I)) (90% yield) as a white solid as polymorph Form A.

Example 5C

[00588] 3-(l-Aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (Compound 9) and 6-chloro-9- (tetrahydro-2H-pyran-2-yl)-9H-purine (Compound 4) are combined in the presence of triethylamine and isopropyl alcohol. The reaction solution is heated at 82 °C for 24 hours to afford Compound 10. The intermediate compound 10 is treated with concentrated HCl and ethanol under aqueous conditions at 35 °C to remove the tetrahydropyranyl group to yield (S)-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2- phenylisoquinolin-l(2H)-one. Isolation/purification under aqueous conditions affords polymorph Form C.

Example 6

Synthesis of (S)-3-(l-(9H^urin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

[00589] 3-(l-Aminoethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one (Compound 9) (150 g; 90% ee) and 6- chloro-9-(tetrahydro-2H-pyran-2-yl)-9H-purine (Compound 4) (216 g, 1.8 equiv) were charged to a round bottom flask followed by addition of IPA (1.2 L; 8 vol) and triethylamine (175 mL; 2.5 equiv). The resultant slurry was stirred at reflux for one day. Heptane (1.5 L; 10 vol) was added dropwise over two hours. The batch was then cooled to 0-5 °C, held for one hour and filtered. The cake was washed with heptane (450 mL; 3 vol) and returned to the reactor. IPA (300 mL; 2 vol) and water (2.25 L; 15 vol) were added and the resultant slurry stirred at 20-25 °C for three and half hours then filtered. The cake was washed with water (1.5 L; 10 vol) and heptane (450 mL; 3 vol) and then vacuum dried at 48 °C for two and half days to give 227 g (90.1 %) of the intermediate (Compound 10) as an off-white solid with >99% (AUC) purity and >94 ee (chiral HPLC). The ee was determined by converting a sample of the cake to the final product and analyzing it with chiral HPLC.

[00590] The intermediate (Compound 10) (200 g) was slurried in an ethanol (900 mL; 4.5 vol) / water (300 mL; 1.5 vol) mixture at 22 °C followed by addition of cone. HC1 (300 mL; 1.5 vol) and holding for one and half hours at 25-35 °C. Addition of HC1 resulted in complete dissolution of all solids producing a dark brown solution. Ammonium hydroxide (260 mL) was added adjusting the pH to 8-9. Product seeds of polymorph Form C (0.5 g) (Form A seeds can also be used) were then added and the batch which was held for ten minutes followed by addition of water (3 L; 15 vol) over two hours resulting in crystallization of the product. The batch was held for 3.5 hours at 20-25 °C and then filtered. The cake was washed with water (1 L; 5 vol) followed by heptane (800 mL; 4 vol) and vacuum dried at 52 °C for 23 hours to give 155.5 g (93.5%) of product with 99.6% (AUC) purity and 93.8% ee (chiral HPLC).

Example 7

-3-(l-(9H-purin-6-ylamino)ethyl)-8-chloro-2-phenylisoquinolin-l(2H)-one

[00591] A mixtue of isopropanol (20.20 kg, 8 vol.), Compound 9 (3.17 kg, 9.04 mol, 1 eq.), Compound 4 (4.61 kg, 16.27 mol, 1.8 eq.) and triethylamine (2.62 kg, 20.02 mol, 2.4 eq.) was prepared and heated to an internal temperature of 82 ± 5 °C. The mixture was stirred at that temperature for an additional about 24 h. The temperature was adjusted to 20 ± 5 °C slowly over a period of about 2 h and the solids were isolated via vacuum filtration through a 24″ polypropylene table top filter equipped with a Sharkskin paper. The filter cake was rinsed sequentially with IPA (5.15 kg, 3 vol.), purified water (80.80 kg, 25 vol.) and n-heptane (4.30 kg, 2 vol.). The cake was further dried for about 4 days in vacuo at 50 ± 5 °C to afford Compound 10.

[00592] To a mixture of ethanol (17.7 kg, 5 vol.) and Compound 10 (4.45 kg, 8.88 mol. 1.0 eq.) was added purified water (8.94 kg, 2 vol.). To this mixture was slowly added concentrated HC1 (3.10 kg, 3.5 eq.) while maintaining the temperature below about 35 °C. The mixture was stirred at 30 ± 5 °C for about 1.5 h and HPLC analysis indicated the presence the compound of Formula (I) in 99.8% (AUC) purity with respect to compound 10.

[00593] Then, the compound of Formula (I) mixture was cooled to 25 ± 5 °C. The pH of the mixture was adjusted to about 8 using pre filtered ammonium hydroxide (1.90 kg). After stirring for about 15 min, Form C crystal seeds (13.88 g) were added. After stirring for about 15 min, purified water (58.0 kg, 13 vol.) was charged over a period of about 2 h. After stirring the mixture for 15 h at 25 ± 5 °C, the solids were isolated via vacuum filtration through a 24″ polypropylene table top filter equipped with a PTFE cloth over Sharkskin paper. The filter cake was rinsed with purified water (18.55 kg, 4 vol.) followed by pre -filtered n-heptane (6.10 kg, 2 vol.). After conditioning the filter cake for about 24 h, HPLC analysis of the filter cake indicated the presence the compound of Formula (I) in about 99.2% (AUC) purity.

[00594] To the filter cake was added dichloromethane (29.9 kg, 5 vol.) and the slurry was stirred at 25 ± 5 °C for about 24 h. The solids were isolated via vacuum filtration through a 24″ polypropylene table top filter equipped with a PTFE cloth over Sharkskin paper, and the filter cake was rinsed with DCM (6.10 kg, 1 vol.). After conditioning the filter cake for about 22 h, the filter cake was dried for about 2 days in vacuo at 50 ± 5 °C to afford the compound of Formula (I) in 99.6% (AUC) purity. The compound of Formula (I) was consistent with a Form A reference by XRPD.

[00595] To this solid was added purified water (44.6 kg, 10 vol.) and pre filtered 2-propanol (3.0 kg, 0.8 vol.). After stirring for about 6 h, a sample of the solids in the slurry was analyzed by XRPD and was consistent with a Form C reference. The solids were isolated via vacuum filtration through a 24″ polypropylene table top filter equipped with a PTFE cloth over Sharkskin paper, and the filter cake was rinsed with purified water (22.35 kg, 5 vol.) followed by pre filtered n-heptane (9.15 kg, 3 vol.). After conditioning the filter cake for about 18 h, the filter cake was dried in vacuo for about 5 days at 50 ± 5 °C.

[00596] This process afforded a compound of Formula (I) in about 99.6% (AUC) purity, and a chiral purity of greater than about 99% (AUC). An XRPD of the solid was consistent with a Form C reference standard. ^:H NMR (DMSO-<i₆) and IR of the product conformed with reference standard.

 

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KEY     Duvelisib, IPI-145,  INK-1197, AbbVie, INFINITY, chronic lymphocytic leukemia, phase 3, orphan drug

Albaconazole

7-chloro-3-[(2R,3R)-3-(2,4-difluorophenyl)-3-hydroxy-4-(1,2,4-triazol-1-yl)butan-2-yl]quinazolin-4-one

Albaconazole (UR-9825) is a triazole antifungal. It has potential broad-spectrum activity.

Albaconazole is a broad-spectrum antifungal agent being evaluated in phase II clinical trials by Stiefel for the oral treatment of fungal infections, including toenail fungus, distal onychomycosis and subungual onychomycosis. Early clinical trials for the treatment of tinea pedis have been completed. In September 2005, Uriach, originator of albaconazole, granted Stiefel exclusive rights to develop and market albaconazole on a worldwide basis. In November 2006, Uriach’s R&D pipeline was transferred to Palau Pharma, a newly-created spin-out company. Under the terms of the agreement with Stiefel, Palau retains rights as comarketing partner in some European countries. In August 2013, Palau Pharma granted worldwide rights to Actavis. A triazole, albaconazole, has shown potent activity against a broad range of organisms, including pathogens resistant to other antifungals, such as fluconazole or itraconazole. It will be developed as an oral and topical formulation, and is expected to be available to the medical community for a variety of dermatological indications and fungal infections, including vulvovaginal candidiasis.

Albaconazole

Systematic (IUPAC) name
7-Chloro-3-[(2R,3R)-3-(2,4-difluorophenyl)-3-hydroxy-4-(1,2,4-triazol-1-yl)butan-2-yl]quinazolin-4-one
Clinical data
Identifiers
CAS number	187949-02-6
ATC code	None
PubChem	CID 208952
ChemSpider	181045
UNII	YDW24Y8IAB
KEGG	D09702
ChEMBL	CHEMBL298817
Chemical data
Formula	C20H16ClF2N5O2
Mol. mass	431.823146 g/mol

The condensation of the chiral oxazolidinone (I) with 2,4-difluorophenacyl bromide (II) by means of NaHMDS in THF/Et2 O gives the chiral oxirane (III), which is treated with LiOH and H2O2 to eliminate the chiral auxiliary, yielding the carboxylic acid (IV). The cleavage of the oxirane ring of (IV) with 1,2,4-triazole (V) and NaH in hot DMF affords the chiral hydroxyacid (VI), which is submitted to Curtius rearrangement by means of DPPA in hot pyridine to provide the chiral oxazolidinone (VII). The cleavage of the oxazolidinone ring of (VII) by means of refluxing aq. HCl gives the chiral aminoalcohol (VIII), which is condensed with 2-amino-4-chlorobenzoic acid (IX) by means of DCC and HOBt to yield the corresponding amide (X). Finally, this compound is cyclized to the target quinazolinone by reaction with triethyl orthoformate in hot dioxane/NMP.

The condensation of the chiral oxazolidinone (I) with 2,4-difluorophenacyl bromide (II) by means of NaHMDS in THF/Et2 O gives the chiral oxirane (III), which is treated with LiOH and H2O2 to eliminate the chiral auxiliary, yielding the carboxylic acid (IV). The cleavage of the oxirane ring of (IV) with 1,2,4-triazole (V) and NaH in hot DMF affords the chiral hydroxyacid (VI), which is submitted to Curtius rearrangement by means of DPPA in hot pyridine to provide the chiral oxazolidinone (VII). The cleavage of the oxazolidinone ring of (VII) by means of refluxing aq. HCl gives the chiral aminoalcohol (VIII), which is condensed with 2-amino-4-chlorobenzoic acid (IX) by means of DCC and HOBt to yield the corresponding amide (X). Finally, this compound is cyclized to the target quinazolinone by reaction with triethyl orthoformate in hot dioxane/NMP.

EP 0783501; ES 2107376; ES 2120885; JP 1998508317; US 5807854; WO 9705130

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The condensation of (R)-lactic acid (I) with morpholine (II) gives the corresponding morpholide (III), which is protected at the hydroxyl position with dihydropyran (IV) to yield the tetrahydropyranyl ether (V). The Grignard reaction of (V) with 2,4-difluorophenylmagnesium bromide (VI) affords the chiral 1-propanone (VII), which by a Corey’s diastereoselective epoxidation with trimethylsulfoxonium iodide is converted into the oxirane (VIII). The opening of the oxirane ring of (VIII) by means of 1,2,4-triazole (IX) and NaH provides the tertiary alcohol (X), which is treated with pyridine p-toluenesulfonate to give the deprotected diol (XI) as a (2R,3R) and (2R,3S) 4:1 diastereomeric mixture, from which the desired (2R,3R)-isomer (XII) was isolated by crystallization. The reaction of (XII) with Ms-Cl and TEA, followed by cyclization with NaOMe, yields the oxirane (XIII), which is finally condensed with 7-chloroquinazolin-4(3H)-one (XIV) by means of K2CO3 in hot NMP.

ES 2159488; WO 0166519

…………………………………………….

Alternatively, intermediate (XIII) can be obtained as follows: Heating of ethyl (S)-lactate (XIV) with morpholine affords amide (XVI), which then reacts with 3,4-dihydro-2H-pyran (A) in the presence of p-TsOH to give protected derivative (XVII). Grignard reaction between (XVII), bromo derivative (XVIII) and Mg turnings in THF yields protected ketone (XIX), which is treated with pyridinium p-toluenesulfonate (PPTS) (THP group removal) and reprotected by means of Tf2O and DIEA to give triflate derivative (XX). Conversion of (XX) into intermediate (XIII) is achieved by reaction with triazolone (VII) and NaH in THF.

Chem Pharm Bull 1993,41(6),1035-42

……………………………………

Alternatively, derivative (XXIX) can be obtained in an analogous way as its enantiomer (XIX). Diastereoselective epoxidation of (XXIX) with trimethylsulfoxonium iodide and NaH in DMSO provides oxirane (XXX) (3). THP group removal by means of PPTS in EtOH, followed by reaction with 3,5-dinitrobenzoyl chloride (XXXI) and NaHCO3 in CH2Cl2, yields a diastereomeric mixture from which dinitrobenzoate derivative (2R,3R)-(XXXII) is obtained by recrystallization (1). Hydrolysis of (2R,3R)-(XXXII) in MeOH by treatment with aqueous NaOH gives compound (2R,3R)-(XXXIII), which is converted into ester (2R,3S)-(XXXIV) by Mitsunobu reaction with benzoic acid, Ph3P and DEAD in THF. Subsequent debenzoylation of (2R,3S)-(XXXIV) with NaOMe in MeOH affords oxiranyl ethanol derivative (2R,3R)-(XXXV), which is first converted into its triflate derivative by means of Tf2O and DIEA in CH2Cl2, and then into triazolone derivative (2S,3R)-(XXXVI) by reaction with intermediate (VII) and NaH in CH2Cl2/DMF. Finally, oxirane derivative (2S,3R)-(XXXVI) reacts with triazole (XXVI) and NaH in DMF to furnish the desired product.

…………………………………………………..

ER-30346 is synthesized by thiazole ring formation of (2R,3R)-3-(2,4-difluorophenyl)-3-hydroxy-2-methyl-4-(1H-1,2,4-triazol-1-yl)thiobutanamide (I) and 4-bromoacetylbenzonitrile (II) by means of reflux in methanol. The thioamide (I) is obtained with excellent yield from a chiral nitrile (III) by heating with diethyl dithiophosphate in aqueous medium.

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The nitrile (III), a chiral key intermediate of this synthesis, can be obtained by two different synthetic routes as follows: Route-a: The key step of this route is ring opening reaction of the trisubstituted oxirane (VII) by cyanide anion leading to the nitrile (III). The chiral oxirane (VII) is synthesized from (R)-lactic acid derivatives as already reported. The reaction of (VII) with diethylaluminum cyanide in toluene or lithium cyanide in tetrahydrofuran gives the nitrile (III) with high yield without any epimerization reaction.

…………………………………………..

The nitrile (III), a chiral key intermediate of this synthesis, can be obtained by two different synthetic routes as follows: Route-b: The starting material of this route is methyl (S)-3-hydroxy-2-methylpropionate (VIII), which contains one additional carbon between the hydroxyl group and the 2-position carbon of (R)-lactate, the starting material of route-a. The hydroxyl group of (VIII) is protected by triphenylmethyl group. Then, 2,4-difluorophenyl moiety is introduced to give the ketone (X). Direct conversion of the ketone (X) to the oxirane (XIV) by dimethylsulfoxonium methylide, the same condition for compound (IV) in route-a, does not proceed. The oxirane (XIV) having desired stereochemistry is obtained via oxidation reaction. The ketone (X) is converted to the exomethylene (XI) by Wittig reaction. The stereoselective oxidation of (XI) is achieved by means of osmium tetroxide in the presence of 4-methylmorpholine N-oxide to give the diol (XII) in 58% yield after separation of its epimer by column chromatography. After methanesulfonylation of the primary alcohol of (XII), a triazole moiety is introduced and the triphenylmethyl group is deprotected. Then, the primary hydroxyl group of (XVI) is oxidized under Swern oxidation condition to give the aldehyde (XVII), which is converted to the chiral nitrile intermediate (III) by means of heating with hydroxylamine-O-sulfonic acid.

………………………………..

A series of azole antifungal agents featuring a quinazolinone nucleus have been subjected to studies of structure−activity relationships. In general, these compounds displayed higher in vitro activities against filamentous fungi and shorter half-lives than the structures described in our preceding paper. The most potent products in vitro carried a halogen (or an isostere) at the 7-position of the quinazolinone ring. Using a murine model of systemic candidosis, oral activity was found to be dependent on hydrophobicity, which, in turn, modulated the compound’s half-life. The 7-Cl derivative, (1R,2R)-7-chloro-3-[2-(2,4-difluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl]quinazolin-4(3H)-one (20, UR-9825), was selected for further testing due to its high in vitro activity, low toxicity, good pharmacokinetic profile, and ease of obtention. Compound 20 is the (1R,2R) isomer of four possible stereoisomers. The other three isomers were also prepared and tested. The enantiomer (1S,2S) and the (1R,2S) epimer were inactive, whereas the (1S,2R) epimer retained some activity. In vitro 20 was superior to fluconazole, itraconazole, SCH-42427, and TAK-187 and roughly similar to voriconazole and ER-30346. In vivo, 20 was only moderately active in a mouse model of systemic candidosis when administration was limited to the first day. This was attributed to its short half-life in that species (t_1/2 = 1 h po). Protection levels comparable to or higher than those of fluconazole, however, were observed in systemic candidosis models in rat and rabbit, where the half-life of the compound was found to be 6 and 9 h, respectively. Finally, 20 showed excellent protection levels in an immunocompromised rat model of disseminated aspergillosis. The compound showed low toxicity signs when administered to rats at 250 mg/kg qd or at 100 mg/kg bid during 28 days.

The condensation of the chiral oxazolidinone (I) with 2,4-difluorophenacyl bromide (II) by means of NaHMDS in THF/Et2 O gives the chiral oxirane (III), which is treated with LiOH and H2O2 to eliminate the chiral auxiliary, yielding the carboxylic acid (IV). The cleavage of the oxirane ring of (IV) with 1,2,4-triazole (V) and NaH in hot DMF affords the chiral hydroxyacid (VI), which is submitted to Curtius rearrangement by means of DPPA in hot pyridine to provide the chiral oxazolidinone (VII). The cleavage of the oxazolidinone ring of (VII) by means of refluxing aq. HCl gives the chiral aminoalcohol (VIII), which is condensed with 2-amino-4-chlorobenzoic acid (IX) by means of DCC and HOBt to yield the corresponding amide (X). Finally, this compound is cyclized to the target quinazolinone by reaction with triethyl orthoformate in hot dioxane/NMP.

J Med Chem 1998,41(11),1869

http://pubs.acs.org/doi/abs/10.1021/jm9707277

 (1R,2R)-7-Chloro-3-[2-(2,4-difluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl]quinazolin-4(3H)-one (20, UR-9825). Precipitated from EtOH/H₂O (66% yield from amine 11):  white amorphous solid;

mp 93−110 °C (wide range);

IR (KBr) ν 1675, 1601, 1554, 1498 cm^-1;

¹H NMR (300 MHz, CDCl₃) 8.58 (s, 1H, NCH-N), 8.26 (d, J = 8.6, 1H, arom), 8.11 (d, J = 5.7, trace rotamer), 7.76 (s, 2H, triazol),

7.74 (d, J = 5.3, 1H, arom), 7.5 (m, 2H, arom), 7.10 (s, trace rotamer), 6.9−6.7 (m, 2H, arom),

5.91 (dq, J_d = 2, J_q = 7, 1H, MeCH), 5.54 (d, J = 2, 1H, OH),

5.15 (d, J = 14.2 1H, CH(H)), 4.9−4.7 (m, trace rotamer), 4.30 (d, trace rotamer), 3.99 (d, J = 14.2, 1H, CH(H)),

1.46 (d, J = 6.9, trace rotamer), 1.29 (d, J = 7, 3H, CHMe);

GC−MS 224 (Tr-CH₂COHAr, C₁₀H₈F₂N₃O), 208 (group N-ethylheterocycle, C₁₀H₉ClN₂O);

[α]_D −8.0° (c 1, CHCl₃).

Chiral HPLC (column, CicloBond SN 1; eluent, MeOH: Et₃NHOAc in H₂O at pH7 1:1; retention times:  (S,S) (74) t_R 12.6 min; (R,R) (20) t_R 13.7 min). Area ratio:  0.01:99.99.

Anal. (C₂₀H₁₆ClF₂N₅O₂) C, H, N. 

KEY
Albaconazole,UNII-YDW24Y8IAB, UR-9825, UR 9825, W-0027

//

Synthesis offers potential routes to analogues of vitamin-D-based drug

Paricalcitol, an A-ring-modified 19-nor analogue of 1α,25-dihydroxyvitamin D₂, is currently used for the treatment and prevention of secondary hyperparathyroidism associated with chronic renal failure.

Read more

http://www.chemistryviews.org/details/ezine/6508291/New_Route_to_Paricalcitol.html

Abbott (Originator), Tetrionics (Bulk Supplier)

Paricalcitol (chemically it is 19-nor-1,25-(OH)₂-vitamin D₂. Marketed by Abbott Laboratories under the trade name Zemplar) is a drugused for the prevention and treatment of secondary hyperparathyroidism (excessive secretion of parathyroid hormone) associated withchronic renal failure. It is an analog of 1,25-dihydroxyergocalciferol, the active form of vitamin D₂ (Ergocalciferol).

Paricalcitol is a synthetic vitamin D analog. Paricalcitol has been used to reduce parathyroid hormone levels. Paricalcitol is indicated for the prevention and treatment of secondary hyperparathyroidism associated with chronic renal failure.

Medical uses

Its primary use in medicine is in the treatment of secondary hyperparathyroidism associated with chronic kidney disease.^[2] In three placebo-controlled studies, chronic renal failure patients treated with paricalcitol achieved a mean parathyroid hormone (PTH) reduction of 30% in six weeks. Additionally there was no difference in incidence of hypercalcemia or hyperphosphatemia when compared to placebo.^[3] A double-blind randomised study with 263 dialysis patients showed a significant advantage over calcitriol (also known as activated vitamin D₃; a similar molecule to 1,25-dihydroxyergocalciferol, adding a methyl group on C₂₄ and lacking a double-bond in the C₂₂ position). After 18 weeks, all patients in the paricalcitol group had reached the target parathormone level of 100 to 300 pg/ml, versus none in the calcitriol group.^[4] Combination therapy with paricalcitol and trandolapril has been found to reduce fibrosis inobstructive uropathy.^[5] Forty-eight week therapy with paricalcitol did not alter left ventricular mass index or improve certain measures of diastolic dysfunction in 227 patients with chronic kidney disease.^[6]

Patents

Mechanism of action

Like 1,25-dihydroxyergocalciferol, paricalcitol acts as an agonist for the vitamin D receptor and thus lowers the bloodparathyroid hormone level.^[1]

Pharmacokinetics

Within two hours after administering paricalcitol intravenous doses ranging from 0.04 to 0.24 µg/kg, concentrations of paricalcitol decreased rapidly; thereafter, concentrations of paricalcitol declined log-linearly. No accumulation of paricalcitol was observed with multiple dosing.^[9]

vitamin D is a fat-soluble vitamin. It is found in food, but also can be formed in the body after exposure to ultraviolet rays. Vitamin D is known to exist in several chemical forms, each with a different activity. Some forms are relatively inactive in the body, and have limited ability to function as a vitamin. The liver and kidney help convert vitamin D to its active hormone form. The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. Vitamin D aids in the absorption of calcium, helping to form and maintain healthy bones.

The 19-nor vitamin D analogue, Paricalcitol (I), is characterized by the following formula:

In the synthesis of vitamin D analogues, a few approaches to obtain a desired active compound have been outlined previously. One of the methods is the Wittig-Homer attachment of a 19-nor A-ring phosphine oxide to a key intermediate bicyclic-ketone of the Windaus-Grundmann type, to obtain the desired Paricalcitol, as is shown for example in U.S. Pat. Nos. 5,281,731 and 5,086,191 of DeLuca.

The synthesis of Paricalcitol requires many synthetic steps which produce undesired by-products. Therefore, the final product may be contaminated not only with a by-product derived from the last synthetic step of the process but also with compounds that were formed in previous steps. In the United States, the Food and Drug Administration guidelines recommend that the amounts of some impurities be limited to less than 0.1 percent.

U.S. Pat. Nos. 5,281,731 and 5,086,191 of DeLuca disclose a purification process of Paricalcitol by using a HPLC preparative method.

As the unwanted products have almost the same structure as the final product, it may difficult to get a sufficiently pure drug substance, vitamin D analogue, using this route to purify the drug substance. Moreover, the high polarity of Paricalcitol makes it very difficult to purify by HPLC and to recover the solid product. Furthermore, HPLC preparative methods are generally not applicable for use on industrial scale. There remains a need in the art to provide a method of preparing the vitamin D analogue Paricalcitol in a sufficiently pure form which is applicable for use on an industrial scale.

Paricalcitol (chemical name: 19-nor-1α,3β,25-trihydroxy-9,10-secoergosta-5(Z),7(Z),22(E)-triene; Synonyms: 19-nor-1,25-dihydroxyvitamin D₂, Paracalcin) is a synthetic, biologically active vitamin D analog of calcitriol with modifications to the side chain (D2) and the A (19-nor) ring. Paricalcitol inhibits the secretion of parathyroids hormone (PTH) through binding to the vitamin D receptor (D. M. Robinson, L. J. Scott, Drugs, 2005, 65 (4), 559-576) and it is indicated for the prevention and treatment of secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease (CKD).

Paricalcitol is marketed under the name Zemplar®, which is available as a sterile, clear, colorless, aqueous solution for intravenous injection (each mL contains 2 microgram (2 μg) or 5 μg paricalcitol as active ingredient) or as soft gelatin capsules for oral administration containing 1 μg, 2 μg or 4 μg paricalcitol.

The molecular formula of paricalcitol is C₂₇H₄₄O₃ which corresponds to a molecular weight of 416.65. It is a white, crystalline powder and has the following structural formula:

Historically, nor-vitamin D compounds were described in 1990 as a new class of vitamin D analogs wherein the exocyclic methylene group C(19) in ring A has been removed and replaced by two hydrogen atoms (see e.g. WO 90/10620). So far, two different routes have been discovered for the synthesis of such 19-nor-vitamin analogs which specifically may be used for the preparation of paricalcitol.

The first synthesis of paricalcitol is disclosed in WO 90/10620 (additional patents from patent family: EP patent no. 0 387 077, U.S. Pat. No. 5,237,110, U.S. Pat. No. 5,342,975, U.S. Pat. No. 5,587,497, U.S. Pat. No. 5,710,294 and U.S. Pat. No. 5,880,113) and generally described in Drugs of the Future, 1998, 23, 602-606.

Example 3 of WO 90/10620 provides the preparation of 1α,25-dihydroxy-19-nor-vitamin D₂ (Scheme 1) by using experimental conditions analogous to the preparation of 1α,25-dihydroxy-19-nor-vitamin D₃. According to this description the starting material 25-hydroxyvitamin D2 is first converted to 1α,25-dihydroxy-3,5-cyclovitamin D₂ (a2) using the procedures published by DeLuca et al. in U.S. Pat. No. 4,195,027 and Paaren et al. published in J. Org. Chem., 1980, 45, 3252. Acetylation of compound a2 followed by dihydroxylation of the exocyclic methylene group using osmium tetroxide in pyridine gives the 10,19-dihydroxy compound a4 which is converted with sodium metaperiodate (diol cleavage) to the 10-oxo-intermediate a5. Reduction of the 10-oxo group in a5 is carried out by treatment with sodium borohydride in a mixture of ethanol and water giving the corresponding 10-hydroxy derivative a6. Mesylation of the 10-hydroxy group in a6 (→a7) followed by reduction with lithium aluminium hydride in THF gives the 10-deoxy intermediate a8 wherein the 1-OAcyl group was simultaneously cleaved during the reduction step. Solvolysis (cycloreversion) of a8 by treatment with hot (55° C.) acetic acid results in the formation of two monoacetates (a9 and a10) which are separated and purified by using HPLC. Finally both monoacetates are saponified with aqueous potassium hydroxide in methanol yielding paricalcitol which is purified by HPLC.

The preparation of paricalcitol according to the method provided in WO 90/10620 has several drawbacks:

• • (1) the starting material 25-hydroxyvitamin D2 is one of the major metabolites of vitamin D2 and not readily available in larger amounts. Additional efforts have to be made in order to synthesize the starting material in sufficient amounts resulting in a protractive and unattractive total synthesis of paricalcitol. Examples for the preparation of 25-hydroxyvitamin D2 are described e.g. in U.S. Pat. No. 4,448,721; WO 91/12240; Tetrahedron Letters, 1984, 25, 3347-3350; J. Org. Chem., 1984, 49, 2148-2151 and J. Org. Chem., 1986, 51, 1264-1269;
  • (2) the use of highly toxic osmium tetroxide which requires special precaution for its handling;
  • (3) use of HPLC for separation of isomers and purification of the final compound. As teached in WO 2007/011951 paricalcitol is difficult to purify by HPLC and as a preparative method HPLC is generally not applicable for use on industrial scale;
  • (4) the yields for the preparation of paricalcitol are not described in WO 90/10620. Generally, the provided yields for the preparation of the analogue compound 1α,25-dihydroxy-19-nor-vitamin D3 are very low especially for the corresponding steps 7 to 11 (yield starting from 1α,25-dihydroxy-10-oxo-3,5-cyclo-19-nor-vitamin D3 1-acetate which is the vitamin D3 analogue to a5 in Scheme1: step 7: 63.4%, steps 8-10: 10.7%, step 11: 51.7%; overall yield starting with step 7: 3.5%).

Another strategy for synthesizing 19-nor vitamin D compounds is disclosed in EP 0 516 410 (and corresponding U.S. Pat. No. 5,281,731, U.S. Pat. No. 5,391,755, U.S. Pat. No. 5,486,636, U.S. Pat. No. 5,581,006, U.S. Pat. No. 5,597,932 and U.S. Pat. No. 5,616,759). The concept is based on condensing of a ring-A unit, as represented by structure b1 (Scheme 2), with a bicyclic ketone of the Windaus-Grundmann type, structure b2, to obtain 19-nor-vitamin D compound (b3).

Specific methods for synthesizing compounds of formula b1 are shown in Schemes 3, 4 and 5. According to Scheme 3, the route starts with the commercially available (1R,3R,4R,5R)(−)quinic acid (b4). Esterification of b4 with methanol followed by protection of the l- and 3-hydroxygroup using tert.-butyldimethylsilyl chloride (TBDMSCl) gives compound b5. Reduction of the ethyl ester in b5 yields b6 which is subjected to a diol cleavage giving compound b7. The 4-hydroxy group is protected as trimethylsilylether resulting in the formation of b8 which is further converted in a Peterson reaction with ethyl (trimethylsilyl)acetate before being deprotected with dilute acetic acid in tetrahydrofurane (THF). The resulting compound b9 is treated with 1,1-thiocarbonyldiimidazole to obtain b10. Subsequent reaction with tributyltin hydride in the presence of a radical initiator (AIBN) gives b11. Compound b11 is then reduced with DIBAH to the allylalcohol b12 which is then reacted with NCS and dimethyl sulfide giving the allylchloride b13. Finally the ring A synthon b14 is prepared by treatment of the allychloride b13 with lithium diphenylphosphide followed by oxidation with hydrogen peroxide.

In an alternative method for synthesizing the ring A unit (Scheme 3), the intermediate b5 can be also subjected to radical deoxygenation using analogues conditions as previously described, resulting in the formation of b16. Reduction of the ester (→b17), followed by diol cleavage (→b18) and Peterson reaction gives intermediate b11 which can be further processed to b14 as outlined in Scheme 3.

Another modification for the preparation is shown in Scheme 5. As described, b7 can be also subjected to the radical deoxygenation yielding intermediate b18 which can be further processed to b14 as depicted in Schemes 3 and 4.

In EP 0 516 411 (and its counterpart, U.S. Pat. No. 5,086,191) is disclosed the preparation of intermediates useful for the synthesis of 19-nor vitamin D compounds (Scheme 6). The key step is the condensation of compounds c1 which can be prepared in an analogous manner as previously described for e.g. b14 (Scheme 3) with compounds c2, resulting in compounds of formula c3.

EP 0 516 411 discloses that Grignard coupling of hydroxy-protected 3-hydroxy-3-methylbutylmagnesium bromide with compound c5 (Scheme 7) can give hydroxy-protected 1α,25-dihydroxy-19-nor vitamin D3 or coupling of the corresponding 22-aldehyde c3 (X¹=X²=TBDMS, R¹=—CHO) with 2,3-dimethylbutyl phenylsulphone can give after desulfonylation, 1α-hydroxy-19-norvitamin d2 in hydroxy-protected form.

An additional method for preparation of 1α-hydroxy-19-nor-vitamin D compounds is provided in EP 0 582 481 (and corresponding U.S. Pat. No. 5,430,196, U.S. Pat. No. 5,488,183, U.S. Pat. No. 5,525,745, U.S. Pat. No. 5,599,958, U.S. Pat. No. 5,616,744 and U.S. Pat. No. 5,856,536) (Scheme 8). Similar to the strategy as described above and shown in schemes 3 to 7, the basis for preparing 1α-hydroxy-19-nor-vitamin D compounds is an independent synthesis of ring A synthon and ring C/D synthon which are finally coupled resulting in vitamin analogs.

Thus the synthesis of 1α-hydroxy-19-nor-vitamin D compounds comprises the coupling of either the ketone d1 with the acetylenic derivatives d2 or ketone d4 with acetylenic derivatives d3, yielding compounds of formula d5. Partial reduction of the triple bond giving d6 followed by reduction using low-valent titanium reducing agents results in the formation of 7,8-cis and 7,8-trans-double bond isomers (d7). Compounds of formula d7 can be also obtained directly from d5 by reaction of d5 with a metal hydride/titanium reducing agent. The isomeric mixture of compounds of formula d7 may be separated by chromatography to obtain separately the 7,8-trans-isomer. The 7,8-cis-isomer of structure d7 can be isomerized to yield the corresponding 7,8-trans-isomer. Finally any protecting groups, if present, can be then removed to obtain 1α-hydroxy-19-nor-vitamin D compounds.

The main disadvantage of the strategies as shown in Schemes 3 to 8 is the fact that ring A as well as ring C/D of the vitamin D derivative has to be separately synthesized before coupling them to compounds like 1α-hydroxy-nor-vitamin D or a protected precursor thereof. According to literature procedure, the ring fragment C/D can be prepared from vitamin D2 by ozonolysis (see e.g. J. C. Hanekamp et al., Tetrahedron, 1992, 48, 9283-9294) from which the ring A is cleaved (and disposed). This fragment has then to be separately synthesized e.g. by using other sources or starting materials like quinic acid in up to 10 steps or more. Therefore such strategies for the total synthesis of 1α-hydroxy-nor-vitamin D compounds become protractive and unattractive for large scale and according to the procedures provided in these patents, the final compounds are obtained only in amounts of <10 mg and in most cases even <1 mg.

Paricalcitol is an active Vitamin D Analog. Paricalcitol is used for the treatment and prevention of secondary hyperparathyroidism associated with chronic kidney disease.

It has been shown to reduce parathyroid hormone levels by inhibiting its synthesis and secretion.

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………………………………….

The 25-hydroxyvitamin D2 (I) is converted into the cyclovitamin D2 acetate (II) according to known methods. The dihydroxylation of the methylene group of (II) with OsO4 in pyridine gives vicinal diol (III), which is oxidized with NaIO4 yielding the ketonic cyclovitamin (IV). The reduction of the ketonic group of (IV) with NaBH4 in ethanol/water affords the corresponding hydroxy derivative (V), which is treated with mesyl chloride and triethylamine to give the mesylate (VI). The reduction of (VI) with LiAlH4 in THF yields the 19-nor-cyclovitamin D (VII), which is treated with hot acetic acid to afford both monoacetates (VIII) and (IX), separated by HPLC. Finally, both monoacetates (VIII) and (IX) are hydrolyzed with KOH in methanol.

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EXAMPLEShttp://www.google.com/patents/US20070149489

Example 1 Crystallization of Paricalcitol from Acetone

500 mg of Paricalcitol were dissolved in 75 ml of acetone in a sonicator at 28° C. over a period of 15 minutes. The clear solution was filtered through glass wool into another flask, and the solution was then concentrated by evaporation, until the volume was 57.5 ml acetone (control by weight). The solution was cooled to −18° C., and the temperature was maintained at −18° C. for 20 hours. The crystals were filtered and washed with 20 ml of cold (−18° C.) acetone, then dried at high vacuum in an oven at 28° C. for 22 hours to obtain a yield of 390 mg (purity of 98.54%).

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http://www.google.com/patents/US20110184199

FIG. 3 is a flow chart showing a detailed example for the synthesis of paricalcitol according to route A1.

FIG. 4 is a flow chart showing the general synthesis of paricalcitol according to route A1.

FIG. 5 is a flow chart showing a detailed example for the synthesis of paricalcitol according to route B1.

FIG. 6 is a flow chart showing the general synthesis of paricalcitol according to route B1.

FIG. 7 is a flow chart showing the general synthesis of paricalcitol using Julia olefination for installation of the side chain according to route B2.

FIG. 8 is a flow chart showing a detailed example for the synthesis of paricalcitol according to route C1.

FIG. 9 is a flow chart showing the general synthesis of paricalcitol according to route C1.

FIG. 10 is a flow chart showing the general synthesis of paricalcitol using Julia olefination for installation of the side chain according to route C2.

Example B11Process Step 12Deprotection of IM-A10b(I) and IM-A10b(II) to Paricalcitol

A mixture consisting of IM-A10b(I) and IM-A10b(II) (41 mg, HPLC purity 54.8%) was dissolved in 1M TBAF in THF (1.5 mL) at temperature 20-25° C. and stirred for 2 h. Then, the reaction mixture was diluted with MeOH (1.5 mL) and 2M aqueous NaOH (0.3 mL) was added. The mixture was stirred for another 2 h and monitored by TLC. Then AcOEt (20 mL) and saturated aqueous NaHCO₃ solution (20 mL) were added and the phases separated. The organic phase was washed with brine (20 mL), dried over MgSO₄ and concentrated under reduced pressure. The product was purified by column chromatography on silica gel (15 g), with mobile phase cyclohexane/AcOEt (100:0 to 92:8).

Yield 11 mg (81%).

In an additional purification, the product (Paricalcitol, 11 mg) was dissolved in acetone (1 mL) at 35-40° C. The solution was filtered and then cooled to −18° C. to initiate crystallization. The obtained slurry was stirred for 15 min at room temperature (20-25° C.) and again cooled to −18° C. for 3.5 h. The solid material was filtered off, washed with cold (−18° C.) acetone (0.25 mL) and dried in vacuo (6 mbar, 40° C.).

Yield of paricalcitol: 4 mg (36%, HPLC purity 98.3%)

Example C7Process Step 12Hydrolysis of IM-A11a to Paricalcitol

To a solution of IM-A11a(I) and IM-A11a(II) (5.24 g, HPLC-purity 94.2%) in EtOH (80 mL) was added at room temperature (20-25° C.) 2M aqueous NaOH solution (8 mL). The reaction mixture was stirred for 1 h 20 min (TLC monitoring), then EtOAc (8 mL) was added and the mixture was concentrated under reduced pressure to a volume of 40 mL whereupon the crystallization started. Water (50 mL) was added to the suspension and after stirring for 75 min at room temperature the solid was isolated by filtration (pH of the mother liquor measured 8-9). The wet product was slurried in EtOH/H₂O (24 g, 1:1) at room temperature, filtered, washed with EtOH/H₂O (5 mL, 1:1) and dried (40° C., 10 mbar).

Yield of paricalcitol: 4.26 g (89.5%, HPLC-purity 97.7%).

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References

Systematic (IUPAC) name
(1R,3R,7E,17β)-17-[(1R,2E,4S)-5-hydroxy-1,4,5-trimethylhex-2-en-1-yl]-9,10-secoestra-5,7-diene-1,3-diol
Clinical data
Trade names	Zemplar
AHFS/Drugs.com	monograph
MedlinePlus	a682335
Pregnancy cat.	AU: C US: C
Legal status	AU: Prescription Only (S4) CA: ℞-only UK: POM US: ℞-only
Routes	Oral, Intravenous
Pharmacokinetic data
Bioavailability	72%[1]
Protein binding	99.8%[1]
Metabolism	Hepatic[1]
Half-life	14-20 hours[1]
Excretion	Faeces (74%), urine (16%)[1]
Identifiers
CAS number	131918-61-1
ATC code	H05BX02
PubChem	CID 5281104
IUPHAR ligand	2791
DrugBank	DB00910
ChemSpider	4444552
UNII	6702D36OG5
ChEMBL	CHEMBL1200622
Synonyms	(1R,3S)-5-[2-[(1R,3aR,7aS)-1-[(2R,5S)-6-hydroxy-5,6-dimethyl-3E-hepten-2-yl]-7a-methyl-2,3,3a,5,6,7-hexahydro-1H-inden-4-ylidene]ethylidene]-cyclohexane-1,3-diol
Chemical data
Formula	C27H44O3
Mol. mass	416.636 g/mol

more………….

Imatinib

CAS No:- [152459-95-5]

IUPAC Name:- 4-[(4-Methyl-1-piperazinyl)methyl]-N-[4-methyl-3-[[4-(3-pyridinyl)-2-pyrimidinyl]amino]phenyl]benzamide

M. P.:- 211-213 °C

MW: 493.604

4-[(4-methylpiperazin-1-yl)methyl]-N-(4-methyl-3-{[4-(pyridin-3-yl)pyrimidin-2-yl]amino}phenyl)benzamide

-[(4-methylpiperazin-1-yl)methyl]-N-(4-methyl-3-{[4-(pyridin-3-yl)pyrimidin-2-yl]amino}phenyl)benzamide

Imatinib (INN), marketed by Novartis as Gleevec (Canada, South Africa and the USA) or Glivec (Australia, Europe and Latin America), and sometimes referred to by its investigational name STI-571, is a tyrosine-kinase inhibitor used in the treatment of multiple cancers, most notably Philadelphia chromosome-positive (Ph⁺) chronic myelogenous leukemia (CML).^[1]

Like all tyrosine-kinase inhibitors, imatinib works by preventing a tyrosine kinase enzyme, in this case BCR-Abl, fromphosphorylating subsequent proteins and initiating the signalling cascade necessary for cancer growth and survival, thus preventing the growth of cancer cells and leading to their death by apoptosis.^[2] Because the BCR-Abl tyrosine kinase enzyme exists only in cancer cells and not in healthy cells, imatinib works as a form of targeted therapy—only cancer cells are killed through the drug’s action.^[3] In this regard, imatinib was one of the first cancer therapies to show the potential for such targeted action, and is often cited as a paradigm for research in cancer therapeutics.^[4]

Imatinib has been cited as the first of the exceptionally expensive cancer drugs, costing $92,000 a year. Doctors and patients complain that this is excessive, given that its development costs have been recovered many times over, and that the costs of synthesizing the drug are orders of magnitude lower. In the USA, the patent protecting the active principle will expire on 4 January 2015 while the patent protecting the beta crystal form of the active principal ingredient will expire on 23 May 2019.^[5]

The developers of imatinib were awarded the Lasker Award in 2009 and the Japan Prize in 2012.^[6][7]

bcr-abl kinase (green), which causes CML, inhibited by imatinib (red; small molecule).

Medical uses

Imatinib is used to treat chronic myelogenous leukemia (CML), gastrointestinal stromal tumors (GISTs) and a number of othermalignancies.

Chronic myelogenous leukemia

The U.S. Food and Drug Administration (FDA) has approved imatinib as first-line treatment for Philadelphia chromosome-positive CML, both in adults and children. The drug is approved in multiple Philadelphia chromosome-positive cases of CML, including after stem cell transplant, in blast crisis, and newly diagnosed.^[8]

Gastrointestinal stromal tumors

The FDA first granted approval for advanced GIST patients in 2002. On 1 February 2012, imatinib was approved for use after the surgical removal of KIT-positive tumors to help prevent recurrence.^[9] The drug is also approved in unresectable KIT-positive GISTs.^[8]

Other

The FDA has approved imatinib for use in adult patients with relapsed or refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL), myelodysplastic/ myeloproliferative diseases associated with platelet-derived growth factor receptor gene rearrangements, aggressive systemic mastocytosis without or an unknown D816V c-KIT mutation, hypereosinophilic syndrome and/or chronic eosinophilic leukemia who have the FIP1L1-PDGFRα fusion kinase (CHIC2 allele deletion) or FIP1L1-PDGFRα fusion kinase negative or unknown, unresectable, recurrent and/or metastaticdermatofibrosarcoma protuberans.^[8] On 25 January 2013, Gleevec was approved for use in children with Ph+ ALL.^[10]

For treatment of progressive plexiform neurofibromas associated with neurofibromatosis type I, early research has shown potential for using the c-KIT tyrosine kinase blocking properties of imatinib.^{[11][12][13][14]}

Legal challenge to generics

In 2007, imatinib became a test case through which Novartis challenged India’s patent laws. A win for Novartis would make it harder for Indian companies to produce generic versions of drugs still manufactured under patent elsewhere in the world. Doctors Without Borders argues a change in law would make it impossible for Indian companies to produce cheap generic antiretrovirals (anti-HIV medication), thus making it impossible for Third World countries to buy these essential medicines.^[43] On 6 August 2007, the Madras High Court dismissed the writ petition filed by Novartis challenging the constitutionality of Section 3(d) of Indian Patent Act, and deferred to the World Trade Organization (WTO) forum to resolve the TRIPS compliance question. As of 2009 India has refused to grant patent exclusivity..

On April 01, 2013 Supreme Court of India dismissed the plea of Novartis for the grant of patent.

in germany

Mechanism of action

Imatinib
Drug mechanism
Crystallographic structure of tyrosine-protein kinase ABL (rainbow colored, N-terminus = blue, C-terminus = red) complexed with imatinib (spheres, carbon = white, oxygen = red, nitrogen = blue).[31]
Therapeutic use	chronic myelogenous leukemia
Biological target	ABL, c-kit, PDGF-R
Mechanism of action	Tyrosine-kinase inhibitor
External links
ATC code	L01XE01
PDB ligand id	STI: PDBe, RCSB PDB
LIGPLOT	1iep

Imatinib is a 2-phenyl amino pyrimidine derivative that functions as a specific inhibitor of a number of tyrosine kinase enzymes. It occupies the TK active site, leading to a decrease in activity.

There are a large number of TK enzymes in the body, including the insulin receptor. Imatinib is specific for the TK domain inabl(the Abelson proto-oncogene), c-kit and PDGF-R (platelet-derived growth factorreceptor).

In chronic myelogenous leukemia, the Philadelphia chromosome leads to a fusion protein of abl with bcr(breakpoint cluster region), termed bcr-abl. As this is now aconstitutively active tyrosine kinase, imatinib is used to decrease bcr-abl activity.

The active sites of tyrosine kinases each have a binding site for ATP. The enzymatic activity catalyzed by a tyrosine kinase is the transfer of the terminal phosphate from ATP to tyrosine residues on its substrates, a process known as protein tyrosinephosphorylation. Imatinib works by binding close to the ATP binding site of bcr-abl, locking it in a closed or self-inhibited conformation, and therefore inhibiting the enzyme activity of the protein semi-competitively.^[32] This fact explains why many BCR-ABL mutations can cause resistance to imatinib by shifting its equilibrium toward the open or active conformation.^[33]

Imatinib is quite selective for bcr-abl – it does also inhibit other targets mentioned above (c-kit and PDGF-R), but no other knowntyrosine kinases. Imatinib also inhibits the abl protein of non-cancer cells but cells normally have additional redundant tyrosine kinases which allow them to continue to function even if abl tyrosine kinase is inhibited. Some tumor cells, however, have a dependence on bcr-abl.^[34] Inhibition of the bcr-abl tyrosine kinase also stimulates its entry in to the nucleus, where it is unable to perform any of its normal anti-apoptopic functions.^[35]

The Bcr-Abl pathway has many downstream pathways including the Ras/MapK pathway, which leads to increased proliferation due to increased growth factor-independent cell growth. It also affects the Src/Pax/Fak/Rac pathway. This affects the cytoskeleton, which leads to increased cell motility and decreased adhesion. The PI/PI3K/AKT/BCL-2 pathway is also affected. BCL-2 is responsible for keeping the mitochondria stable; this suppresses cell death by apoptosis and increases survival. The last pathway that Bcr-Abl affects is the JAK/STAT pathway, which is responsible for proliferation.^[36]

synthesis

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Imatinib is known as an inhibitor of protein-tyrosine kinase and is indicated for the treatment of chronic myeloid leukemia (CML). Imatinib also has potential for the treatment of various other cancers that express these kinase including acute lymphocyte leukemia and certain solid tumors. It can also be used for the treatment of atherosclerosis, thrombosis, restenosis, or fibrosis. Thus, imatinib can also be used for the treatment of non-malignant diseases. Imatinib is usually administered orally in the form of a suitable salt, e.g., in the form of imatinib mesylate.

The chemical name of Imatinib is 4-(4-methyl piperazine -1- methyl) -N-4-methyl-3-[4- (3- pyridyl) pyrimidine-2-amino] – benzamide and is represented by the following structural formula:

(Imatinib)

Imatinib Mesylate is an inhibitor of signal transduction (STI571) invented by Novartis AG after 7 years of hard work; it is the first inhibitor of cancer signal transduction ratified in the whole world. It is sold by Novartis as Gleevec capsules containing imatinib mesylate in amounts equivalent to 100 mg or 400 mg of imatinib free base.

Imatinib Mesylate is the rare drug in America, European Union and Japan. In May 10, 2001, it was ratified by American Food and Drug Administration (FDA) to treat the chronic myelogenous leukemia patients. EP0564409 (US5521 184) describes the process for the preparation of imatinib and the use thereof, especially as an anti tumour agent.

There are generally two synthetic routes for synthesis of Imatinib, suitable for the industrial production. One synthetic process as described in scheme-I comprises using 2-methyl-5-nitroaniline as the raw material which is reacted with cyanamide to obtain guanidine; cyclization reaction with 3-dimethylamino-l-(3-pyridyl)-2-propylene-l- ketone; reduction step of nitro to amine and condensation reaction with 4- (Chloromethyl)benzoyl chloride and N-methylpiperazidine to obtain Imatinib (WO 2004/108669). -I

Scheme-2 describes the successful process for the synthesis of Imatinib using 4-methyl-3- nitroanilines as the raw material, comprising reacting 4-methyl-3-nitroanilines with 4- (Chloromethyl)benzoyl chloride and N-methyl piperazidine in turns; followed by reduction of nitro group to amino group; then reaction with cyanamide to obtain guanidine; finally cyclization reaction with 3- dimethyl amino- 1 -(3- pyridyl)-2- propylene-1 -ketone to obtain Imatinib (WO 03/066613). The said PCT application discloses the use of 4-4-(methyl piperazin-l-ylmethyl)-benzoic acid methyl ester as one of the raw material but rest of the reactants are different from that of N-(5-amino -2- methylphenyl)-4-(3-pyridyl)-2-pyrimidine amine in presence of trimethyl aluminium.

Scheme-2

Common feature of the processes for preparing imatinib according to (WO 2004/108669) and (WO03/066613) lies in use of cyanamide as a reagent. The main difference between the two routes is that the reaction sequence of cyclization of pyrimidine chain is different. Example 10 of PCT International Publication no. WO 2003/066613 is less applicable to industrial purposes. These include the reaction between N-(3-bromo-4-methyl-phenyl)-4- (4-methyl-piperazin-l -ylmethyl)-benzamide and 4-(3-pyridyl)-2-pyrimidineamine which uses a mixture of rac-BINAP (a phosphine oxide catalyst) and Pd₂ (dba)₃*CHCl₃. These catalysts are very expensive, therefore, their use is unfit for commercial production.

CN1630648A describes a process comprising reaction of 3- bromine-4- methyl aniline with 4-(4-methyl-piperazin- methyl) methyl benzoate in presence of trimethyl-Aluminum to obtain N-(4-methyl-3-bromobenzene)-4-(4-methyl-piperazin- 1 -methyl)-benzamide, which further reacts with 2-amino-4-(3-pyridyl)- pyrimidine in presence of palladium as catalyst to obtain Imatinib.

The drawback of the above process is the use of trimethyl-Aluminum, which is flammable and reacts severely when comes in contact with water.

CN101016293A describes another process using N-(4-methyl-3-3- aminophenyl)-4-(4- methyl-piperazin-1 -methyl)- benzamide as the raw material. The said raw material is reacted with 2-halogen-4-(3-pyridyl)- pyrimidine to obtain Imatinib.

The process disclosed in CN 101016293 A comprises use of halogenated agent, such as phosphorus oxychloride, which is used to synthesize 2-halogeno-4- methyl- (3-pyridyl) – pyridine is lachrymator and corrosive and has great influence to the surroundings. EP0564409 describes a coupling reaction between N-(5-amino -2-methylphenyl)-4-(3- pyridyl)-2-pyrimidine amine and 4-(4-methyl piperazin-l-ylmethyl)-benzoyl chloride in the presence of high quantity of pyridine to starting reactant amine N-(5-amino -2- methylphenyl)-4-(3-pyridyl)-2-pyrimidine amine. The ratio of the pyridine to the said reactant is 138 which is equivalent to about 40 parts v/w. Use of such a large quantity of pyridine is unsafe as it is a toxic solvent according to ICH guidelines. The workup of the reaction comprises evaporation of the remaining pyridine and further processing, which finally involves chromatography for purification, which is highly undesirable on industrial scale because it is expensive and time consuming.

US2006/0149061 and US20060223817 also discloses a similar synthetic approach comprising the use of similar pyridine /starting amine ratio (140 equivalents which is equals about 41 parts v/w). The product obtained is purified by slurring in ethyl acetate.

WO2004/074502 describes a coupling reaction between N-(5-amino -2-methylphenyl)-4- (3-pyridyl)-2-pyrimidine amine and 4-(4-methyl piperazin-l-ylmethyl)-benzoyl chloride wherein solvent like dimethyl pharmamide , dimethyl acetamide, N-methyl pyrilidinone are used as solvents instead of pyridine. However the method described in this patent application lacks an advantage in that the coupling reaction produces the hydrohalide salt of imatinib, e.g. imatinib trihydrochloride monohydrate, which has to be treated with a base in order to afford the imatinib base, thus an extra step is required. Further, conventional methods for coupling N-(5-amino -2-methylphenyl)-4-(3-pyridyl)-2- pyrimidine amine require reaction with an acid halide, e.g. 4-(4-methyl piperazin-1- ylmethyl)-benzoyl chloride, which requires an additional production step that can involve harsh and/or toxic chlorinating agent.

WO2008/1 17298 describes a coupling reaction between N-(5-amino -2-methylphenyl)-4- (3-pyridyl)-2-pyrimidine amine and 4-(4-methyl piperazin-l-ylmethyl)-benzoyl chloride in presence of a base selected from potassium carbonate, sodium carbonate, potassium or sodium hydroxide. Use of potassium carbonate as base results into the formation of Imatinib dihydrochloride which ultimately requires an additional operation of neutralization by using excessive base to get imatinib.

WO2008/136010 describes a coupling reaction between N-(5-amino -2-methylphenyl)-4- (3-pyridyl)-2-pyrimidine amine and 4-(4-methyl piperazin-l-ylmethyl)-benzoyl chloride in presence of base potassium hydroxide resulting into 78.6% yield of crude imatinib base. Preparation of crude requires imatinib hydrochloride preparation during the workup which is then basified to get base in crude form. This also describes maleate salt preparation as mode of purification which is again basified to give pure Imatinib base.

US patent application 2004/0248918 discloses a different approach using N-(5-amino -2- methylphenyl)-4-(3-pyridyl)-2-pyrimidine amine and 4-(2-chloromethyl)-benzoyl chloride as raw material. The reaction for the preparation of Imatinib is carried out in tetrahydrofuran as a reaction solvent and in the presence of pyridine as a base. However the method described in this patent application lacks an advantage as purification of the product requires column chromatography using chloroform: methanol (3: 1 v/v), which is not suitable purification method when performing the reaction on large scale, followed by crystallizati

US patent application 2008/0103305 discloses a process comprising reacting N-(5-amino -2-methylphenyl)-4-(3-pyridyl)-2-pyrimidine amine or its alkyl derivative and an acid salt of 4-[(4-methyl-l-piperazinyl)-methyl] benzoyl derivative as given below in the scheme-3 using pyridine in an amount of about 2 to 10 volumes per gram of the said amine. However the drawback associated with this process is use of pyridine especially when reaction is performed on large scale. -3

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SYNTHESIS

Inverse synthetic analysis will be divided into four imatinib into fragment A has 1,3 – parents electrical, fragment B are 1,3 – parent nuclear, fragments A and B constitute a pyrimidine ring.

Compound 4 can be obtained in two ways, benzyl bromide 1 and secondary amines 2 by SN2 reaction, or the aldehyde 3 with a secondary amine 2 by reductive amination. Sodium cyanoborohydride electron withdrawing effect of the cyano group, thereby reducing the activity of the negative hydrogen, it may be present in acidic solution. Also in the acidic conditions of aldehydes and secondary amines imine positive ions, which is higher than the activity of aldehyde reduction.This is why the reductive amination reagent with inert negative and hydrogen under acidic conditions. 4 hydrolyzed ester with thionyl chloride into the acid chloride 5 . The reaction of aniline and cyanamide dinucleophile guanidine 7 . Compound 8 and DMF-DMA reaction electrophilic reagent parents 9 , 7 , and 9 ring closure under alkaline conditions to generate 10 . Finally, reduction, amidation, and a salt of imatinib mesylate generated.

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An efficient, economic process has been developed for the production of imatinib with 99.99% purity and 50% overall yield from four steps. Formation and control of all possible impurities is described. The synthesis comprises the condensation of N-(5-amino-2-methylphenyl)-4-(3-pyridinyl)-2-pyrimidineamine with 4-(4-methylpiperazinomethyl)benzoyl chloride in isopropyl alcohol solvent in the presence of potassium carbonate to yield imatinib base.

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DOI: 10.1039/C2OB27003J

http://pubs.rsc.org/en/content/articlelanding/2013/ob/c2ob27003j#!divAbstract

Imatinib (1), nilotinib (2) and dasatinib (3) are Bcr-Abl tyrosine kinase inhibitors approved for the treatment of chronic myelogenous leukemia (CML). This review collates information from the journal and patent literature to provide a comprehensive reference source of the different synthetic methods used to prepare the aforementioned active pharmaceutical ingredients (API’s).

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Organic Process Research & Development, 12(3), 490-495. DOI: 10.1021/op700270n As an example of research aimed at industrial production one involving imatinib. This cancer drug was one of the first offspring of rational drug design and if you believe the Wikipedia page hugely expensive despite its simple appearance (no stereocenters!). A group of Northwest University researchers set out to improve the existing Novartis procedure DOI and here is how they did it. 2-acetylpyridine (1) was alkylated with the acetal of N,N-dimethylformamide 2 to enamine 3. A pyrimidine ring in 5was formed with base and reagent guanidine nitrate 4 and nitrotoluene fragment 6 was added in a Ullmann-type reaction with CuI generating secondary amine 7. The nitro group was reduced by hydrazine / FeCl3/C to the amine which was then converted to amide 8 with acid chloride 9. The final step is addition of piperazine 10 to form imatinib11. So is this procedure an improvement on the existing method and ready-made for industrial implementation? Surely they have eradicated the use of toxic cyanamide, cumbersome sodium metal and expensive palladium but they have also introduced equally toxic hydrazine and the harmful and explosive guanidine nitrate. As a further point of criticism the final step is demonstrated on a 0.5 gram scale. If the journal Organic Process Research & Development would live up to its standards the scale would at least be a kilogram. Liu, Y., Wang, C., Bai, Y., Han, N., Jiao, J., Qi, X. (2008). A Facile Total Synthesis of Imatinib Base and Its Analogues. Organic Process Research & Development, 12(3), 490-495. DOI: 10.1021/op700270n …………………………………………. Tetrahedron Lett. 2007, 48, 3455. DOI: 10.1016/j.tetlet.2007.03.033 Angelo Carotti and his group from University of Bari have developed a solid-phase synthesis of Imatinib which acts as a selective tyrosine kinase inhibitor (Tetrahedron Lett. 2007, 48, 3455. DOI: 10.1016/j.tetlet.2007.03.033). By applying microwave heating in five steps of the synthesis (preparation of linker 1, nucleophilic substitution, reduction of the nitro group, formation of guanidine and final cyclization) the total process could be accelerated. Key steps were the guanylation of aniline 2 where a higher yield and purity of product 3 could be obtained under microwave irradiation, and the final cyclization to resin bound Imatinib where the reaction time could be reduced from 20 h to 50 min. Addiotionally, resin stability was ensured due to the shorter reaction time. ……………………………… ……………………………………. http://www.google.com/patents/EP2509973A1?cl=en   process for the preparation of imatinib, which comprises the reaction of 4-Methyl-N-(4-pyridin-3-yl-pyrimidin-2-yl)- benzene-l,3-diamine (II) also referred as N-(5-amino -2-methylphenyl)-4-(3-pyridyl)-2- pyrimidine amine with 4-(4-Methyl-piperazin-l-ylmethyl)-benzoic acid ester (III) in the presence of a base in a suitable solvent to yield substantially pure imatinib base in about 90% yield. R is C1-C4 alkyl group The preparation of 4-Methyl-N-(4-pyridin-3-yl-pyrimidin-2-yl)-benzene-l,3-diamine (II) and 4-(4-Methyl-piperazin-l-ylmethyl)-benzoic acid ester (III) may be carried out according to prior art methods. Compound of formula (II) can be synthesized by the process disclosed in WO2004/ 108669 comprising reacting 2-methyl-5-nitroaniline with 50% aqueous solution of cyanamide to obtain N-(2- Methyl-5-nitrophenyl)-guanidinium nitrate, which further reacted with 3-dimethylamino- l-pyridin-3-yI-propenone to yield (2-methyI-5-nitrophenyl)-(4-pyridin-3-yI-pyrimidin -2- yl)-amine, finally, reduction of nitro group to obtain compound of formula (Π). Componds of formula (III) can be synthesized by the process disclosed in synthtic communications 2003, 3597 comprising reacting a-halogen-/?-toluinitrile or methanesulfonic acid 4-cyano-benzyl ester or toluene-4-sulfonic acid 4-cyano-benzyl ester with N-methylpiperazine, followed by hydrolysis of the cyano to acid which formed as dihydrochloride contain half crystalline hydrate, finally reaction with alcohol to obtain compound of formula (III). The synthetic route for preparing imatinib according to the present invention is is given below   EXAMPLES Example 1 To a solution of 4-Methyl-N-(4-pyridin-3-yl-pyrimidin-2-yl)-benzene-l,3-diamine (27.7g) and 4-(4-Methyl-piperazin-l-ylmethyl)-benzoic acid methyl ester (50g) in Tetrahydrofuran (250ml), a solution of sodium methylate (lOg) in methanol (10ml) was added. The reaction mixture was heated to reflux. After completion of the reaction solution was poured into ice-water and a large amount of solid precipitated, which was filtered and washed with water and dried to obtain Imatinib base (45g). Yield: 91%. The spectral data is as follows: Ή NMR ( 500M , DMSO ) δ : 10.2 (s, lH), 9.30 (s, 1H), 8.99 (s, 1H), 8.72 (d, J=4.0 Hz, 1H), 8.57 (s, 1H), 8.53 (s, 1H), 8.11 (s, 1H), 8.00 (s, 1H), 7.98 (s, 1H), 7.58-7.51 (m, 4H), 7.44 (d, J=4.3 Hz, 1H), 7.22 (d, J=8.1 Hz, 1H), 3.70 (s, 2H), 3.50-3.25 (m, 2H), 3.20-2.90 (m, 4H), 2.81 (s, 3H), 2.40 (s, 3H), 2.24 (s, 3H). 13C NMR (125M , DMSO ) δ : 164.9, 161.3, 161.1, 159.4, 150.8, 147.7, 137.7, 137.1, 134.9, 134.3, 132.3, 129.9, 129.1, 127.7, 127.6, 123.9, 117.2, 1 16.8, 107.5, 59.9, 52.1, 48.9, 42.2, 17.5. MS (M++l): 494.3   Example 2 To a solution of 4-Methyl-N-(4-pyridin-3-yl-pyrimidin-2-yl)-benzene-l,3-diamine (27.7g) and 4-(4-Methyl-piperazin-l-ylmethyl)-benzoic acid methyl ester (50g) in toluene (250ml), a solution of sodium ethoxide (20g) in methanol (10ml) was added. The reaction mixture was heated to reflux. After completion of the reaction, solution was poured into ice-water and a large amount of solid precipitated, which was filtered and washed with water and dried to obtain Imatinib base (44g). Yield: 91%. Example 3 To a solution of potassium butoxide (250g) in methanol (1000ml), a solution of 4-Methyl- N-(4-pyridin-3-yl-pyrimidin-2-yl)-benzene-l,3-diamine (277g) and 4-(4-Methyl- piperazin-l-ylmethyl)-benzoic acid propyl ester (600g) in Tetrahydrofuran (2500ml) was added. The reaction mixture was stirred at room temperature. After completion of the reaction solution was poured into ice-water and a large amount of solid precipitated, which was filtered and washed with water and dried to obtain Imatinib base (450g). Yield: 91%. Example 4 To a solution of potassium butoxide (25kg) in ethanol (lOOLitre), a solution of 4-Methyl- N-(4-pyridin-3-yI-pyrimidin-2-yl)-benzene-l,3-diamine (27.7kg) and 4-(4-MethyI- piperazin-l-ylmethyl)-benzoic acid ethyl ester (50.0kg) in toluene (250Litre) was added. The reaction mixture was stirred at room temperature. After completion of reaction, solution was poured into ice-water and a large amount of solid precipitated, which was filtered and washed with water, and dried to obtain Imatinib base (40.0kg). Yield: 81%. ………………………………… FIGURE 2. Synthesis of SKI696. (A) isopropanol/sodium hydroxide (a); iron/acetic acid/EtOH/water (b); triethyl amine/acetonitrile (c); 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N,N-dimethylaminopyridine/dimethylformamide (d); trifluoroacetic acid/dichloromethane (e); potassium carbonate/acetonitrile (f). (B) 18F-KF/Kryptofix/1,2-dichlorobenzene (g); dimethylformamide/acetonitrile (h).  http://jnm.snmjournals.org/content/52/8/1301/F2.expansion.html …………………………………. http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-9-265 In order to prepare the core heterocyclic unit a direct condensation between a 1,3-dicarbonyl compound 3.39 and an amidine or guanidine 3.40 is frequently employed (Scheme 36a). Alternatively, an amidine can be condensed with a vinylogous amide 3.41 resulting in the direct formation of 2,4-disubstituted pyrimidines. These condensations often require relatively harsh reaction conditions despite this they are of great value as they involve cheap or easily accessible materials and typically only form water as the principle byproduct. A modification of the above pyrimidine synthesis has been applied in the generation of imatinib (3.36, Gleevec) which is Novartis’ tyrosine kinase inhibitor used for the treatment of chronic myeloic leukaemia. In a patented route the aldol product 3.47 undergoes a condensation reaction with guanidine 3.48 in basic media to give the 2-aminopyrimidine 3.49 (Scheme 37) [93]. After generating the functional pyrimidine core a hydrazine-mediated reduction of the nitro group in the side chain was conducted with Raney-Nickel as the catalyst. Amide formation with 4-chloromethylbenzoyl chloride (3.50) and a direct displacement of the benzylic chloride with N-methylpiperazine (1.118) complete this synthesis of imatinib in excellent overall yields. Scheme 37: Synthesis of imatinib.   One noteworthy feature of this imatinib synthesis is that it is specifically designed for facile isolation of intermediates by precipitation due to their limited solubility in non-polar solvents [94]. Whilst this process was efficient in enabling the isolation of pure material after each step, it does not encourage telescoping of steps, which would in principal increase the overall efficiency of the process. Recently, similar approaches have been utilised in the academic environment using enabling techniques in a route to imatinib. For instance, our group has employed continuous flow synthesis methods to imatinib [95,96]. The route not only afforded imatinib but led to many previously inaccessible derivatives in an automated fashion within a single working day (Scheme 38). In addition, this particular sequence showcases the uses of scavenger resins for in-line purification as the synthesis progresses and features the use of a Buchwald–Hartwig amination in a late stage fragment coupling. While it was sufficient to access only small amounts of these structures (around 50 mg), these techniques are currently being adopted by several major pharmaceutical companies in order to enhance drug development and even manufacturing sequences. Scheme 38: Flow synthesis of imatinib. pick up ref from http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-9-265 ………………………………….. Imatinib is a tyrosine-kinase inhibitor used for the treatment of cancer.  A key steps in its synthesis is the enamine formation highlighted in green below. 1) Show a mechanism for this transformation? 2) This particular enamine is rather stable.  Comment on it relatively high stability?  (i.e. What make it so stable?)   …………………………………….. Org. Biomol. Chem., 2009,7, 5129-5136 DOI: 10.1039/B913333J  http://pubs.rsc.org/en/content/articlelanding/2009/ob/b913333j#!divAbstract Protein kinases catalyze the phosphorylation of serine, threonine, tyrosine and histidine residues in proteins. Aberrant regulation of kinase activity has been implicated in many diseases including cancer. Thus development of new strategies for kinase inhibitor design remains an active area of research with direct relevance to drug development. Abelson (Abl)tyrosine kinase is one of the Src-family of tyrosine kinases and is directly implicated in Chronic Myelogenous Leukemia (CML). In this article, we have, for the first time, developed an efficient method for the construction of small molecule-based bisubstrate inhibitors of Abl kinase using click chemistry. Subsequent biochemical screenings revealed a set of moderately potentinhibitors, a few of which have comparable potency to Imatinib (an FDA-approved drug for treatment of chronic myeloid leukemia) against Abl.   ……………………………………

Medicine for Blood Cancer

‘Imitinef Mercilet’ is a medicine which cures blood cancer.
Its available free of cost at “Adyar Cancer Institute in Chennai”.
Create Awareness. It might help someone.Cancer Institute in Adyar, Chennai

‘Imitinef Mercilet’ is apparently an alternative spelling of the drug Imatinib mesylate which is used in the treatment of some forms of leukemia along with other types of cancer. Imatinib, often referred to a “Gleevec”, has proved to be an effective treatment for some forms of cancers. However, “blood cancer” is a generalized term for cancers that affect the blood, lymphatic system or bone marrow. The three types of blood cancer are listed as leukemia, lymphoma, and multiple myeloma. These three malignancies require quite different kinds of treatments. While drugs (including Imatinib), along with other treatments such as radiation can help to slow or even stop the progress of these cancers, there is currently no single drug treatment that can be said to actually cure all such cancers.

Category: Cancer
Address: East Canal Bank Road , Gandhi Nagar
Adyar, Chennai -600020
Landmark: Near Michael School
Phone: 044-24910754 044-24910754 ,
044-24911526 044-24911526 , 044-22350241

Imatinib is a small molecule selectively inhibiting specific tyrosine kinases that has emerged recently as a valuable treatment for patients with advanced GIST. The use of imatinib as monotherapy for the treatment of GIST has been described in PCT publication WO 02/34727, which is here incorporated by reference. However, it has been reported that primary resistance to imatinib is present in a population of patients, for example 13.7% of patients in one study. In addition, a number of patients acquire resistance to treatment with imatinib. More generally this resistance is partial with progression in some lesions, but continuing disease control in other lesions. Hence, these patients remain on imatinib treatment but with a clear need for additional or alternative therapy.

Imatinib is 4-(4-methylpiperazin-1-ylmethyl)-N-[4-methyl-3-(4-pyridin-3-yl)pyrimidin-2-ylamino)phenyl]-benzamide having the formula I

The preparation of imatinib and the use thereof, especially as an anti-tumour agent, are described in Example 21 of European patent application EP-A-0 564 409, which was published on 6 Oct. 1993, and in equivalent applications and patents in numerous other countries, e.g. in U.S. Pat. No. 5,521,184 and in Japanese patent 2706682

The flow-based route required minimal manual intervention and was achieved despite poor solubility of many reaction components

UK chemists have used a combination of flow chemistry methods with solid-supported scavengers and reagents to synthesise the active pharmaceutical ingredient, imatinib, of the anticancer drug Gleevec. The method avoids the need for any manual handling of intermediates and allows the drug to be synthesised in high purity in less than a day.

Gleevec, developed by Novartis, is a tyrosine kinase inhibitor used for the treatment of chronic myeloid leukaemia and gastrointestinal stromal tumours.

READ ALL AT

http://www.rsc.org/chemistryworld/2013/01/flow-synthesis-anticancer-drug

IMATINIB

CREDIT

http://www.veomed.com/va041542042010

‘Wrapping’ Gleevec Fights Drug-Resistant Cancer, Study Shows

Hydrogenation in flow: homogenous and heterogeneous catalysts using Teflon AF-2400 to effect gas-liquid contact at elevated pressure

http://pubs.rsc.org/en/Content/ArticleLanding/2011/SC/c1sc00055a#!divAbstract

M. O’Brien, N. Taylor, A. Polyzos, I.R. Baxendale, S.V. Ley, Chem. Sci. 2011, 2, 1250-1257.

A Tube-in-Tube reactor/injector has been developed, based on a gas-permeable Teflon AF-2400 membrane, which allows both heterogeneous and homogeneous catalytic hydrogenation reactions to be efficiently carried out at elevated pressure in flow, thereby increasing the safety profile of these reactions. Measurements of the gas permeation through the tubing and uptake into solution, using both a burette method and a novel computer-assisted ‘bubble counting’ technique, indicate that permeation/dissolution follows Henry’s law and that saturation is achieved extremely rapidly. The same gas-permeable membrane has also been shown to efficiently effect removal of excess unreacted hydrogen, thus enabling further downstream reaction/processing.

Homogenous hydn…ABOVE

Heterogenous hydrogenation

M. Amatore, C. Gosmini and J. Périchon, J. Org. Chem., 2006, 71, 6130-6134. \

LAPATINIB

Systematic (IUPAC) name
N-[3-chloro-4-[(3-fluorophenyl)methoxy]phenyl]-6- [5-[(2-methylsulfonylethylamino)methyl]-2-furyl] quinazolin-4-amine
Clinical data
Trade names	Tykerb, Tyverb
AHFS/Drugs.com	monograph
MedlinePlus	a607055
Licence data	EMA:Link, US FDA:link
Pregnancy cat.	AU: D US: D D
Legal status	AU: Prescription Only (S4) CA: ℞-only UK: POM US: ℞-only
Routes	Oral
Pharmacokinetic data
Bioavailability	Variable, increased with food
Protein binding	>99%
Metabolism	Hepatic, mostly CYP3A-mediated (minor 2C19 and2C8 involvement)
Half-life	24 hours
Excretion	Mostly fecal
Identifiers
CAS number	231277-92-2  388082-78-8 (ditosylate)
ATC code	L01XE07
PubChem	CID 208908
DrugBank	DB01259
ChemSpider	181006
UNII	0VUA21238F
Chemical data
Formula	C29H26ClFN4O4S
Mol. mass	581.058 g/mol

Lapatinib (INN), used in the form of lapatinib ditosylate, (USAN) (Tykerb/Tyverb, GSK) is an orally active drug for breast cancerand other solid tumours.^[1] It is a dual tyrosine kinase inhibitor which interrupts the HER2/neu and epidermal growth factor receptor(EGFR) pathways.^[2] It is used in combination therapy for HER2-positive breast cancer. It is used for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress HER2 (ErbB2).^[3]

Status

On March 13, 2007, the U.S. Food and Drug Administration (FDA) approved lapatinib in combination therapy for breast cancer patients already using capecitabine (Xeloda, Roche).^[2][3] In January 2010, Tykerb received accelerated approval for the treatment of postmenopausal women with hormone receptor positive metastatic breast cancer that overexpresses the HER2 receptor and for whom hormonal therapy is indicated.^[3]

Pharmaceutical company GlaxoSmithKline (GSK) markets the drug under the propriety names Tykerb (mostly US) and Tyverb (mostly Europe).^[4] The drug currently has approval for sale and clinical use in the US,^[2][4] Australia,^[2] Bahrain,^[2] Kuwait,^[2] Venezuela,^[2]Brazil,^[5] New Zealand,^[5][6] South Korea,^[5] Switzerland,^[4] Japan, Jordan, the European Union, Lebanon, India and Pakistan.^[4]

On the 2nd of August 2013, India’s Intellectual Property Appellate Board revoked the patent for Glaxo’s Tykerb citing its derivative status, while upholding at the same time the original patent granted for Lapatinib.^[7]

The drug lapatinib ditosylate is classified as S/NM (a synthetic compound showing competitive inhibition of the natural product) that is naturally derived or inspired substrate (Gordon M. Cragg, Paul G. Grothaus, and David J. Newman, Impact of Natural Products on Developing New Anti-Cancer Agents, Chem. Rev. 2009, 109, 3012–3043)

Breast cancer[

Lapatinib is used as a treatment for women’s breast cancer in treatment naive, ER+/EGFR+/HER2+ breast cancer patients(now often called “triple positive”) and in patients who have HER2-positive advanced breast cancer that has progressed after previous treatment with other chemotherapeutic agents, such as anthracycline, taxane-derived drugs, or trastuzumab (Herceptin, Genentech).

A 2006 GSK-supported randomized clinical trial on female breast cancer previously being treated with those agents (anthracycline, a taxane and trastuzumab) demonstrated that administrating lapatinib in combination with capecitabine delayed the time of further cancer growth compared to regimens that use capecitabine alone. The study also reported that risk of disease progression was reduced by 51%, and that the combination therapy was not associated with increases in toxic side effects.^[11] The outcome of this study resulted in a somewhat complex and rather specific initial indication for lapatinib—use only in combination with capecitabine for HER2-positive breast cancer in women whose cancer have progressed following previous chemotherapy with anthracycline, taxanes and trastuzumab.

………………………………………………………..

US6727256

or

http://www.google.co.in/patents/WO1999035146A1

………………………………………………..

http://www.google.com/patents/EP2550269A1?cl=en

Lapatinib has the structural formula (I) and chemical name N-[3- chloro-4-[(3-fluorophenyl)methoxy]phenyl]-6-[5-[(2-methylsulfonylethylamino)methyl]-2- furyl] quinazolin-4-amine.

BACKGROUND ART

Lapatinib is a tyrosine kinase inhibitor that is used as an orally administered drug as its ditosylate salt to treat certain types of advanced or metastatic breast cancer and other solid tumors. Lapatinib ditosylate was approved by the FDA in 2007 and the EMEA in 2008 and is marketed by GlaxoSmithKline (GSK) under the trade name of Tykerb^® in the USA and Tyverb^® in Europe.

Lapatinib substance is claimed in US 6,713,485 B2 and US 6,727,256 Bl and lapatinib ditosylate and its crystalline forms are claimed in US 7,157,466 B2. A synthesis of lapatinib that utilises a palladium mediated coupling of a substituted 4-anilino-6-iodo-quinazoline (II) with a 2- (tributylstannyl)furan (Ilia) is disclosed in US 6,727,256 Bl and is also presented in US 7,157,466 B2. In US 7,157,466 B2 a second generation approach was disclosed that utilises a palladium catalysed coupling of a substituted 4-anilino-6-iodo-quinazoline (II) with furan-2-yl-boronic acids (Illb). Following the palladium catalysed coupling reactions utilised in the two synthetic methods of US 6,727,256 Bl and US 7,157,466 B2, only one (US 7,157,466 B2) or two (US 6,727,256 Bl and US 7,157,466 B2) synthetic modification of the structure are utilised before the lapatinib substance is provided (Scheme 1). The EMEA’s COMMITTEE FOR MEDICINAL PRODUCTS FOR HUMAN USE (CHMP) has published guidelines titled GUIDELINE ON THE SPECIFICATION LIMITS FOR RESIDUES OF METAL CATALYSTS OR METAL REAGENTS and recommendations are presented for oral exposure to metals, including palladium. For a drug being consumed in quantities not exceeding a 10 g daily dose, a limit of 10 ppm (parts per million) concentration of palladium in the drug substance is recommended. Given this, there is still an unmet need for an alternative synthetic method that can be used for preparation of lapatinib in which the palladium mediated coupling step is performed early in the synthetic route, thereby being capable to provide .

Scheme 1

SUMMARY OF THE INVENTION

There are a number of ways that the levels of a metal, such as palladium, can be controlled in a drug substance through purging of the metal by treatment of the drug substance or its synthetic intermediates or both, including crystallisation, aqueous extraction, filtration through metal absorbent filter aids (Organic Process Research & Development 2005, 9, 198-205), precipitation of the metal from solution, chromatography, and treatment with metal scavenging reagents (Organic Process Research & Development 2003, 7, 733-742). By placing the palladium mediated coupling step downstream in the synthetic route, however, to take advantage of synthetic convergence, the opportunity to reduce the level of palladium in the drug substance is reduced. In contrast, however, by redesigning the synthetic route to move the palladium mediated coupling step upstream, further away from the drug substance, increases the opportunity to control the palladium level in the drug substance. Furthermore, by careful operational design (such as in a precipitation and crystallisation step), the palladium level in the intermediates can be consistently controlled. Given that there is a need, the present invention has addressed these two latter points and utilised them in a novel and efficient process for the manufacture of lapatinib and lapatinib ditosylate.

Scheme 2 – Synthesis of lapatinib and lapatinib ditosylate

In contrast to the prior art methods disclosure in US 6,727,256 Bl and US 7,157,466 B2, the present invention has performed a transition metal catalysed coupling reaction at the most upstream point in the synthetic route based on the utilization of commercially available starting materials SMla (6-iodoquinazolin-4(3H)-one) and SM2a (5-formylfuran-2-ylboronic acid), or their analogues SMI and SM2, to provide IM1. Thus, in one aspect of the present invention, lapatinib is made from a novel compound (IM1) (Scheme 2).

In another aspect of the present invention, a lapatinib ditosylate monohydrate is prepared by crystallizing lapatinib ditosylate in a mixture of water, DMSO and MeCN.

In another aspect of the present invention, novel compound IM1 is synthesized by the cross- coupling of commercially available SMla and SM2a, or their analogues SMI and SM2, in suitable solvents comprised of an organic solvent and water in the presence of a base and a catalyst formed from a transition metal and a ligand (scheme 3).

X = CI, Br, I, OTf Y = CHO, or CH(OR)₂

BZ = B(OH)₂, B(OR)₂, [BF₃]M or BR₂

Scheme 3

Example

Example 1: Synthesis of 5-(4-oxo-3,4-dihydroquinazolin-6-yl)furan-2-carbaldehyde (IMl)

IM1

A 5:2 v/v mixture of DMSO and H₂0 (1400 mL) was degassed for 30 min at ambient temperature using nitrogen. 5-Formylfuran-2-ylboronic acid (SM2a; 26.8 g, 193 mmol) was added dissolved in this mixture. [HP(i-Bu)₃] BF₄ ^“ (840 mg, 2.94 mmol) and Pd(OAc)₂ (680 mg, 2.94 mmol) was added and the mixture was stirred at ambient temperature under an atmosphere of nitrogen for 20 min. AcOK (18.8 g, 192 mmol) was added into the reactor and was stirred for 20 min at ambient temperature. 6-Iodoquinazolin-4(3 /)-one (SMla; 40 g, 147 mmol) was added and heated to 80±5°C (internal temperature) in an oil bath under nitrogen, Upon completion of the reaction (HPLC), the reaction mixture was hot-filtered, then hot water (400 mL, 80±5°C) was added into the filtrate. This was slowly cooled to 0-15°C (solid started to precipitate at 70°C (internal temperature) and was then filtered. The filter cake was washed with H₂0 (80 mL), then with MeCN (60 mL), and dried in vacuo at 60+5°C for 6 h to provide 5-(4-oxo-3,4-dihydroquinazolin-6-yl)-furan-2- carbaldehyde (IMl; 34.6 g, 144 mmol) with 99.7 % HPLC purity in 97.6% HPLC yield. ^XH NMR (300 MHz, de-DMSO): δ 7.47 (d, / = 3.8 Hz, 1H), 7.69 (d, / = 3.8 Hz, 1H), 7.77 (d, / = 8.6 Hz, 1H), 8.17 (s, 1H), 8.27 (dd, / = 8.6, 2.1 Hz, 1H), 8.52 (d, = 2.1 Hz, 1H), 9.66 (s, 1H); ¹³C NMR (75 MHz, CDC1₃): δ 110.5, 122, 6, 123.9, 126.0, 127.5, 129.0, 131.4, 147.1, 150.1, 152.7, 157.6, 161.2, 178,8; ESI-MS, Pos: [M+H]⁺ mJz 241; IR (cm ¹): 1713, 1671, 1604,1462; m.p.: 267°C. See Figure 2 for the DSC/TGA of IMl; See Figure 3 for the X-ray powder diffraction pattern of IMl; Residual concentration of palladium: 230 ppm.

Example 2: Synthesis of 5-(4-chloroquinazolin-6-yl)furan-2-carbaldehyde hydrochloride

(IM2a.HCl)

I 1 reflux IM2a.HCI

Over a 1.5 hour period under an atmosphere of N₂, SOCb (86.2 g) in MeCN (145 mL) was added dropwise into a mixture, that had been preheated at reflux for 0.5 h, of IM1 (29 g, 0.121 mol), MeCN (435 mL) and DMF (0.88 g) at reflux. The reaction was terminated when less than 2% (HPLC) of IM1 was remaining. If the reaction did not achieve complete reaction, extra SOCI₂was added. The mixture was cooled to about 25±5°C (internal temperature), and was then filtered and washed with MeCN (58 mL) to give ca. 55 g of IM2a.HCl (moist with MeCN) with 82A purity by HPLC. IM2a.HCl: ¾ NMR (300 MHz, d₆-DMSO): δ 9.68 (s, 1 H), 9.17 (s, 1H), 8.57 (d, / = 2.0 Hz, 1H), 8.46 (dd, J = 8.6, 2.1 Hz, 1H), 8.02 (d, / = 8.6 Hz, 1H), 7.74 (d, = 3.8 Hz, 1H), 7.60 (d, J = 3.8 Hz, 1H). See Figure 5 for the ^XH NMR spectrum of IM2a.HCl; ¹³C NMR (75 MHz, d₆- DMSO) δ 179.0, 159. 6, 156.4, 152.9, 149.5, 141.0, 132.6, 129.2, 125.9, 123.2, 122.9, 122.7, 111.5;

IM2a.HCl was purified by column chromatography (eluent: ) to give pure IM2a. IM2a: ^lH NMR (300 MHz, d₆-DMSO): δ 7.53 (d, / = 3.3 Hz, 1H), 7.68 (d, J = 3.3 Hz, 1H), 8.02 (d, / = 8.7 Hz, 1H), 8.42 (d, / = 8.4 Hz, 1H), 8.54 (d, / = 2.1 Hz, 1H), 8.90 (s, 1H), 9.64 (s, 1H); ¹³C NMR (75 MHz, CDCI3): δ 111.5, 122.8, 122.9, 123.7, 125.9, 129.1, 132.5, 142.1 , 149.3, 152.9, 156.6, 159.7, 179.1.

Example 3: Synthesis of 5-(4-(3-chloro-4-(3-fluorobenzyloxy)phenylamino)

- uinazolin-6-yl)furan-2-carbaldehyde hydrochloride (IM3.HC1)

A mixture of IM2a.HCl (moist with MeCN solvent, prepared from 29 g IM1, 0.120 mol) and 3-chloro-4-(3-fiuorobenzyloxy)aniline (SM3; 27.3 g, 0.108 mol) in MeCN (580 mL) was stirred under reflux, until HPLC analysis showed that the reaction was completed (about 2 h). The mixture was cooled to room temperature (25±5°C), filtered, and washed with MeCN (58 mL). A mixture of the moist crude solid IM3 and THF (870 mL) was treated with a 2.0 N aqueous NaOH (348 mL) and stirred for 3-4 h until most of the solid had dissolved. The mixture was filtered through diatomite and was washed with a saturated aqueous solution of NaCl (87 mL). The organic layer was treated with 10% aqueous HCI (174 mL) and stirred for 0.5 h. The resulting solid was filtered, washed with THF (87 mL), and dried in vacuo at 60+5°C for 16 h to give the crude IM3.HC1 (34 g, 0.067 mol, HPLC purity: 99%).

IM3.HC1: ^:H NMR (300 MHz, d₆-DMSO): δ 9.69 (s, 1H), 9.52 (s, 1H), 8.94 (s, 1H), 8.50 (dd, / = 8.8, 1.7 Hz, 1H), 8.01 (d, / = 8.8 Hz, 1 H), 7.97 (d, J =2.5 Hz, 1H), 7.77 (d, / = 3.8 Hz, 1H), 7.73 (dd, = 9.0, 2.5 Hz, 1H), 7.69 (d, / = 3.8 Hz, 1H), 7.49 (td, 7 = 8.0, 6.1 Hz, 1 H), 7.41-7.28 (m, 3H), 7.20 (td, / = 8.4, 2.2 Hz, 1H), 5.31 (s, 2H).

Free base IM3 is obtained by column chromatography (eluting with EtOAc/DCM, 1:4, v/v). IM3 ^XH NMR (300 MHz, d₆-DMSO): δ 5.28 (s, 2H), 7.19 (td, /= 8.7 Hz, 7 = 2.1 Hz 1H), 7.34 (m, 4H), 7.43 (d, 7 = 3.6 Hz , 1H), 7.49 (m, 1H), 7.73 (dd, 7 = 8.7 Hz 7 = 2.7 Hz, 1H), 7.76 (d, 7 = 3.6 Hz, 1H), 7.88 (d, 7 = 9 Hz, 1H), 8.07 (d, 7 = 2.1 Hz, 1H), 8.32 (dd, 7 = 4.43 Hz, 7 = 1.95 Hz, 1H), 8.95 (d, 7 = 1.5 Hz, 1H), 9.68 (s, 1H).

Example 4: Synthesis of N-(3-chloro-4-(3-fluorobenzyloxy)phenyl)-6-(5-((2- (methylsulfonyl)ethylamino)methyl)furan-2-yl)quinazolin-4-amine ditosylate (lapatinib ditosylate)

I

To a suspension of 2-(methylsulfonyl)ethanamine hydrochloride (SM4.HC1; 12.2 g, 76.7 mmol) in THF (600 mL) was added acetic acid (14.1 g, 235 mmol) followed by DIPEA (30.3 g, 235 mmol) were added. After stirred at ambient temperature for 0.5 h, ¾0 (4.2 g, 233 mmol) and IM3.HC1 (30.0 g, HPLC assay >99%, 58.7 mmol) were added. After being stirred at ambient temperature (20°C) for 4 h, sodium triacetoxyborohydride (37.4 g, 176 mmol) was added and the mixture was stirred at ambient temperature (20°C±5°C; external temperature) until HPLC showed the completion of the reaction. A 10% aqueous solution of sodium hydroxide (90 mL) was added and the mixture was stirred for 30 min. The organic phase was washed with 25% aqueous NH₄C1 (60 mL), filtered, treated with -TsOH (40.4 g, 135 mmol) and heated to reflux for 2 h. The mixture was cooled to ambient temperature and stirred for 3 h at ambient temperature. The mixture was filtered, and the filter cake was washed twice with THF (120 mL each) and was then dried under vacuum at 70±5°C for 6 h to give 43 g (46.5 mmol) lapatinib ditosylate with 99.4% HPLC purity.

Lapatinib ditosylate ^[H NMR (300 MHz, d₆-DMSO): δ 11.41(s, 2H), 9.33 (s, 3H), 9.04 (d, / = 1.3 Hz, 2H), 8.93 (s, 2H), 8.41 (dd, J =8.8, 1.6 Hz, 2H), 7.91 (d, J = 2.6 Hz, 2H), 7.54-7.41 (m, 9H), 7.37 – 7.27 (m, 6H), 7.25 (d, / = 3.4 Hz, 2H), 7.22 – 7.13 (m, 2H), 7.08 (dd, / = 8.4, 0.6 Hz, 8H), 6.87 ( d, / = 3.5 Hz, 2H), 5.29 (s, 4H), 4.46 (s, 4H), 3.65 – 3.51 (m, 4H), 3.51 – 3.38 (m, 4H), 2.26 (s, 12H).

A solution of lapatinib ditosylate was converted to its free base form, lapatinib, by washing a solution with aqueous NaOH followed by concentration. Lapatinib: ^XH NMR (300 MHz, d₆-DMSO): δ 2.98 (t, / = 6.75 Hz, 1H), 3.04 (s, 1H), 3.29 (t, J = 6.6 Hz, 1H), 3.83 (s, 1H), 5.28 (s, 1H), 6.50 (d, / = 3.0 Hz, 1H), 7.08 (d, / = 3.3 Hz, 1H), 7.20 (m, 1H), 7.33 (m, 4H), 7.48 (m, 1H), 7.76 (m, 1H), 7.80 (d, 7 = 9 Hz, 1H), 8.04 (d, 7 = 2.75 Hz, 1H), 8.17 (dd, / = 8.7 Hz, / = 1.8 Hz, 1H), 8.56 (s, 1H), 8.75 (d, J = 1.8 Hz, 1H).

Example 5a: Purification of lapatinib ditosylate

Lapatinib ditosylate (5.0 g, 5.4 mmol, 96.5% HPLC purity with the maximum individual impurity at 0.8%) was dissolved in DMSO (10 mL) at 70°C (internal temperature). MeCN (10 mL) was added dropwise into the mixture at 70-80°C (internal temperature) and was stirred at this temperature for 1 h. Over a 4 h period the mixture was cooled to room temperature. MeCN (30 mL) was added dropwise, and the mixture was stirred for lh, then filtered and washed with MeCN (10 mL). The filter cake was dried under vacuum at 60°C for 16 h to give 4.0 g lapatinib ditosylate as crystalline Form 1 (as disclosed in US 7,157,466 B2) with 99.6% HPLC purity in 78% HPLC yield.

Example 5b. Purification of lapatinib ditosylate.

Lapatinib ditosylate (3 g, 3.25 mmol, 99.3% HPLC purity was dissolved in DMF (18 mL) at 80°C and stirred for 1 hour. The mixture was hot-filtered. MeCN (18 mL) was added into the filtrate at 80°C. The temperature was cooled to 70°C and crystal precipitated. The mixture was kept at 70°C for 1 h and then 60°C for 1 h. The mixture was further cooled to 0°C and stirred for 2 h. The crystals of lapatinib ditosylate were isolated by filtration and were dried at 40°C under vacuum overnight. Lapatinib ditosylate (2.5 g, 2.70 mmol, 83% yield) with 99.9% HPLC purity was obtained. XRPD analysis (figure 9) indicated that this was Form 2 as disclosed in WO 2009/079541 Al.

Example 6: Preparation of lapatinib ditosylate monohydrate Lapatinib ditosylate (2.0 g, 96.7% HPLC purity, 2.1 mmol) was dissolved in DMSO (5 mL) at 80°C (internal temperature) and the solution was filtered whilst the lapatinib ditosylate was still dissolved. A mixture of MeCN (5 mL, 2.5 P) and water (0.3 mL) was then added dropwise into the filtered solution at 70-80°C (internal temperature). The mixture was cooled at a rate of 10°C/h until 60°C, and was kept at 60°C for 2 h and was then slowly cooled down to 50°C. After being kept at 50°C for 1 h, MeCN (15 mL) was added, and then the mixture was cooled to 20-30°C and stirred at 20-30°C for 2 h. The slurry was filtered, washed with MeCN (6 mL) and the filter cake was dried in vacuo at 60°C for 4 h to give lapatinib ditosylate monohydrate (1.7 g, 99.4A% purity, 1.8 mmol). XRPD analysis (figure 10) indicated that this was the monohydrate crystalline form as disclosed in US 7,157,466 B2.

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Beilstein J. Org. Chem. 2013, 9, 2265–2319.

http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-9-265

GlaxoSmithKline’s lapatinib (3.38, Tykerb) is a novel dual kinase inhibitor used in the treatment of solid tumors such as those found in breast cancer and contains a quinazoline core structure. It consists of a 2,5-disubstituted furan ring, which is directly linked to the aminoquinazoline unit (Scheme 41). The quinazoline heterocycle was prepared starting from 5-iodoanthranilic acid (3.72) via initial condensation with formamidine acetate (3.73) followed by chlorination using oxalyl chloride or phosphorous oxychloride [101]. Performing a nucleophilic aromatic substitution on the chloride 3.74 with aniline 3.75renders the extended core of lapatinib. This intermediate (3.76) was then coupled with 5-formyl-2-furanoboronic acid (3.77) using standard Suzuki cross-coupling conditions. Finally, a reductive amination of the pendant aldehyde of3.78 with 2-(methylsulfonyl)ethylamine (3.79) furnishes the desired product lapatinib (Scheme 41).

http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-9-265

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Guntrip SB, Lackey KE, Cockerill GS, Carter MC, Smith KJ Bicyclic heteroaromatic compounpds as protein tyrosine kinase inhibitors. EP 1047694; WO 9935146.

Quinazoline ditosylate salt compounds (US7157466)

A NOVEL PROCESS FOR THE PREPARATION OF Lapatinib AND ITS PHARMACEUTICALLY ACCEPTABLE SALTS ( WO 2010061400)

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Fresenius Kabi Oncology Ltd.WO 2013080218

Lahiri, Saswata; Gupta, Nitin; Singh, Hemant Kumar; Handa, Vishal; Sanghani, Sunil

6 JUNE 2013, http://www.google.com/patents/WO2013080218A1?cl=en

Lapatinib of Formula-(II), was first disclosed by SmithKline Beecham in US Patent No. 6,727,256.

The process for the preparation of Lapatinib of Formula-(II), disclosed in W099/35146, is given in the Scheme-I. Accordingly, 4-chloro-6-iodo-quinazoline of Formula-(IV), is reacted with 3-chloro-4-(3′-fluoro-benzyloxy)-aniline yielding N-[3- chloro-4-{(3'-fluorobenzyloxy) phenyl} ]-6-iodo-quinazoline of Formula-( l). The compound of the Formula-(l) reacts with 5-(l,3-dioxolan-2-yl)-2-(tributylstannyl)furan to get the compound of Formula-(2) which on deprotection with HC1, removes the 1,3- dioxolan-2-yl protecting group and liberates 5-(4-{3-chloro-4-(3-fluoro- benzyloxy)anilino}-6- quinazolinyl)-furan-2-carbaldehyde of Formula-(3). The compound of the Formula-(3) on reaction with 2-methanesulfonylethylamine, followed by reductive amination using sodium (triacetoxy)borohydride as the reducing agent gives the required compound Lapatinib of Formula-(II) as an organic residue, which is purified by column chromatography and subsequently converted into its hydrochloride salt (5).

Subsequently, US 7, 157,466 also discloses the preparation of Lapatinib and its ditosylate salt, which is given in Scheme-II.

Lapatinib ditosylate has been prepared by reacting the tosylate salt of 5-(4-[3- chloro-4-(3-fluorobenzyloxy)-anilino]-6-quinazolinyl)-furan-2-carbaldehyde of Formula (3) with 2-(methylsulfonyl)ethylamine in the presence of base (diisopropyl- ethylamine) followed by reduction with sodium triacetoxyborohydride to obtain Lapatinib base which is converted to Lapatinib ditosylate anhydrate by adding para- toulenesulfonic acid. Conversion to Lapatinib ditosylate monohydrate is carried out using THF/H₂0. Intercon vers ion to the anhydrate of the ditosylate salt and back to monohydrate is carried out with methanol and water respectively.

(lla)

WO201 1039759, filed by Natco Pharma also describes a process for the preparation of Lapatinib from 2-amino benzonitrile, as given in scheme-Ill. Firstly, 2- aminobenzonitrile (6) is reacted with iodine monochloride in acetic acid medium to form compound of Formula (7) which is recrystallized from mixture of hexane and toluene. The compound of Formula (1) is reacted with N,N-dimethylformamide dimethy|acetal in an organic solvent such as toluene or xylene to form novel compound of Formula (8). The compound of Formula (7) is then coupled with compound of Formula (8) in presence of acid catalyst such as trifluoroacetic acid, formic acid or acetic acid to form compound of Formula (3). The compound of Formula (3) is the subjected to Suzuki coupling with 5-formyl-2-furyl boronic acid in ethereal solvent in the presence of catalyst selected from palladium (II) acetate, palladium (II) chloride, and palladium on carbon to form aldehyde compound of Formula (4). The compound of Formula (4) is reacted with 2-methanesulphonyl ethylamine or its salt to produce imine compound of Formula (VI) which is reduced with sodium borohydride to form Lapatinib base (II). The crude Lapatinib base is purified by crystallization from organic solvents. The purified Lapatinib base is converted into Lapatinib ditosylate anhydrous by treating Lapatinib base in organic solvent with /7-toluenesulfonic acid monohydrate which is then recrystallized from aqueous alcohol to produce pharmaceutically acceptable Lapatinib ditosylate monohydrate. The process is depicted in Scheme-Ill.

-IH

Lapatinib (II) WO2010017387, filed by Teva relates to Lapatinib intermediates and process for the preparation of Lapatinib base and Lapatinib ditosylate. The application relates to highly pure intermediate of Formula (2), 3-chloro-4-(3-fluorobenzyloxy)aniline which is prepared by reducing a compound of Formula (1), 3-chloro-4-(3- fluorobenzyloxy)nitrobenzene, with iron and ammonium chloride system in the presence of a C1 -C4 alcohol and water at refluxing temperature. The application also relates to highly pure intermediate of Formula (3), N-[3-chloro-4-(3-fluorobenzyloxy)- phenyl]-6-iodoquinazolin-4-amine, which is prepared in one-pot process from compound of Formula (1 ) by reduction using iron and ammonium chloride system in presence of C1 -C4 alcohol and water. The compound of Formula (3) is reacted with 5- formyl-2-furanboronic acid in the presence of a palladium catalyst and a base in a polar organic solvent to obtain Lapatinib aldehyde base, compound of Formula (4). Optionally, Lapatinib aldehyde base is combined with /? oluenesulfonic acid to obtain Lapatinib aldehyde monotosylate, compound of Formula (5). The invention further provides a process for the preparation of Lapatinib base. Lapatinib aldehyde base or its salt is combined with methylsulfonylethylamine or its hydrochloride salt, acetic acid, an inorganic base in an organic solvent and a reducing agent (sodium triacetoxyborohydride) to form Lapatinib base. Lapatinib base is further purified by using organic solvents. Lapatinib base obtained is further converted to Lapatinib ditosylate. The process is depicted in scheme-IV.

Scheme-IV

Example-5

Preparation of Lapatinib Ditosylate

To a stirred mixture of Sodiumtriacetoxyborohydride (0.21 g) in Tetrahydrofuran (THF)(2.4 ml) was added N-(3-Chloro-4-(3-fluorobenzyloxy)phenyl)-6-(5-((2- (methylsulfonyl)ethylimino)- methyl)furan-2-yl)quinazolin-4-amine (0.2 g) in THF. The reaction mixture was stirred for 1 hour at 20-25 °C. Reaction was monitored by TLC and on completion of reaction, aqueous NaQH (0.16 g NaOH to 0.8 g demineralized water) was added. The organic layer was separated and added p- Toluenesulfonic acid (0.42) in THF (0.6 ml) and stirred for 3 hours. The solid was filtered and dried under vacuum at 60-65°C till constant weight.

Weight: 0.15 g

Yield: 46.9 %

Purity by HPLC: 96.16%

MS (ES+) m/z: 581 [M+H]⁺ & 583 [M+H+2]⁺

1H NMR (400 MHz; DMSO-d6): 2.28 (s, 6H), 3.14 (s, 3H), 3.44 (t, J=8.0 Hz, 2H), 3.55 (t, J=8.0 Hz, 2H), 4.46 (s, 2H), 5.31 (s, 2H), 6.89 (br s, 1H), 7.10 (d, J=7.2 Hz, 4H), 7.20 (m, 1H), 7.23 (br s, 1H), 7.31- 7.36 (m, 3H), 7.47 (d, J=7.2 Hz, 4H), 7.63 (d, J=8.8 Hz, IH), 7.89 (br s, IH), 7.92 (d, J=8.8 Hz, IH), 8.39 (d, J=8.8 Hz, IH), 8.89 (s, IH), 8.98 (s, IH), 9.28 (s, IH, NH), 11.18 (s, IH, NH).

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http://www.google.com/patents/WO2008024439A2?cl=en

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http://www.google.co.in/patents/US7157466

The free base and HCl salts of the compounds of Formulae (I), (II), (III), and (IV), may be prepared according to the procedures of International Patent Application No. PCT/EP99100048, filed Jan. 8, 1999, and published as WO 99/35146 on Jul. 15, 1999, referred to above. A schematic of such procedures is presented in Scheme A following. The specific page references given are to WO 99/35146. The free base of the compound of formula II is used as an example of the general scheme.

The compound of formula (II), i.e., N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methanesulphonyl) ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate has been prepared in two distinct forms, an anhydrate form (Formula II′ in Scheme B) and a monohydrate form (Formula II″ in Scheme B). The relationship of these forms is illustrated in Scheme B below. The anhydrate form of N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methanesulphonyl)ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate may be prepared by (a) reacting the tosylate salt of 5-(4-[3-chloro-4-(3-fluorobenzyloxy)-anilino]-6-quinazolinyl)-furan-2-carbaldehyde (formula B in Scheme B) with 2-(methylsulfone)ethylamine in tetrahydrofuran in the presence of diisopropyl-ethylamine followed by (b) the introduction of this solution into to a slurry of sodium triacetoxyborohydride in tetrahydrofuran at room temperature, (c) adding 5N sodium hydroxide to adjust the pH to within a range of 10–11, (d) separating the organic tetrahydrofuran phase, and then (e) adding para-toulenesulfonic acid hydrate to the organic phase to provide the ditosylate anhydrate. Interconversion to the monohydrate and back to the anhydrate of the ditosylate salt compounds of the invention is as depicted in Scheme B. The tosylate salt of 5-(4-[3-chloro-4-(3-fluorobenzyloxy)-anilino]-6-quinazolinyl)-furan-2-carbaldehyde is prepared from the HCl salt of the carbaldehyde (Formula A of Scheme B). Preparation of N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methanesulphonyl)ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate and the anhydrate and monohydrate forms thereof are utilized as an example. As recognized by those skilled in the art, other compounds of formula I and anhydrate and hydrate forms thereof may be prepared by similar methods.

Compound A of Scheme B may be prepared by various synthetic strategies, other that the strategy recited in Scheme A above, utilizing the palladium(O) mediated coupling of quinazoline and substituted furan intermediates.

Example 8

Preparation of N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methanesulphonyl)ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate anhydrate (Anhydrate Form of Compound of Formula II)

To a 20 L reactor was added 13.3 vol of THF followed by 0.62 wt (2.93 mol) of NaBH(OAc)₃. The 20 L reactor was set to maintain contents at 20° C. A second 20 L reactor was charged with 1000 grams, (1.55 mol) of 5-(4-[3-chloro-4-(3-fluorobenzyloxy)-anilino]-6-quinazolinyl)-furan-2-carbaldehyde 4-methyl benzenesulfonate prepared by the procedure of Example 7 and 6.7 vol of THF. To the THF solution of 5-(4-[3-chloro-4-(3-fluorobenzyloxy)-anilino]-6-quinazolinyl)-furan-2-carbaldehyde 4-methylbenzenesulfonate was added 0.325 vol (1.86 mol) diisopropylethylamine followed by 0.32 wt of 2-(methylsulfone)ethylamine, (321 g, 2.6 mol) and 0.15 vol of IPA. After 1 hour, the preformed imine/THF solution was transferred by vacuum to the stirred suspension of NaBH(OAC)₃ in the first 20 L reactor over 10 minutes. After 90 minutes, 4 vol of 5N NaOH was added over 40 min via a pump. This solution was allowed to stir for 15 minutes after which the stirrer was switched off and the layers were allowed to separate. The aqueous layer was drained from the bottom of the reactor and the organic layer transferred to the empty 20 L reactor through a teflon-lined stainless steel jacketed transfer hose outfitted with an in-line 0.45 μm filter. To this solution was added a 2 vol THF solution of 4 wt (1180 g, 6.2 mole) of p-toluenesulfonic acid monohydrate over 5 min. A yellowish precipitate was observed to come out of solution and this was allowed to stir at room temperature for 12 hours. The reaction was drained from the bottom of the reactor and filtered through a ceramic filter lined with paper. The yellow filter cake was washed with 1 vol of a 95:5 THF water solution and allowed to air dry overnight. After suctioning dry for 12 hours, the yellow filter cake was transferred to two glass trays and placed in the drying oven (42° C.) under house vacuum (18 in Hg) with a nitrogen bleed. The two glass trays were removed from the oven and allowed to cool to room temperature and sampled accordingly. The isolated yield of N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methane-sulphonyl)ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate (anhydrate) was 1264 grams (1.3 wt, 88%; 1443 g Th) and was a yellow solid.

Approximately 50 mg of the product was transferred to a Karl Fisher Volumetric Moisture Apparatus (model DL35, Mettler, Hightstown, N.J.), which was operated according to the manufacturer’s instructions. The anhydrate water content was determined to be 0.31%.

Example 10Preparation of N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methanesulphonyl)ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate monohydrate (Monohydrate Form of Compound of Formula II)

A 20 L reactor was charged with 1 wt (930 g, 1.0 mol) of N-{3-Chloro-4-[(3-fluorobenzyl) oxy]phenyl}-6-[5-({[2-(methanesulphonyl)ethyl]amino}methyl)-2-furyl]-4-quinazolinamine ditosylate anhydrate prepared using the procedure of Example 8. To this was added 10 volumes of a pre-mixed 8:2 THF:deionized water solution and the reactor was heated to 65° C. Complete dissolution was observed at 50° C. The clear reaction mixture was transferred to another 20 L reactor through a stainless steel jacketed transfer hose that was equipped with an in-line 5.0 μm cartridge filter. The empty 20 L reactor and the filter line were washed with 0.2 vol of the pre-mixed 8:2 THF:deionized water solution. An additional 1 vol of pre-mixed 8:2 THF:deionized water solution was used to wash the material into the reaction mixture. The 20 L reactor was heated to ˜80° C. The reaction temperature was then ramped down to 55° C. over 2 hours and then to 45° C. over 10 hours. After 10 hours, the temperature was adjusted to 25° C. and the reaction mixture allowed to stir at room temperature for 45 minutes. The yellow precipitate was drained from the bottom of the 20 L reactor into a ceramic filter lined with paper. The flow was fast and smooth and the filter rate very good. The yellow filter cake was washed with 0.6 volumes of a pre-mixed 8:2 THF:deionized water solution and the yellow solid was air dried for 4 hours and placed into a glass tray. The glass tray was placed in a vacuum oven under house vacuum (˜18 in Hg) at 60° C. with a nitrogen bleed for 2 days. After removal from the oven, the material was sampled accordingly. The yield was 743 grams (0.8 wt, 80%; 930 g th) as a bright yellow, crystalline solid.

Approximately 50 mg of the product was transferred to a Karl Fisher Volumetric Moisture Apparatus (model DL35, Mettler, Hightstown, N.J.), which was operated according to the manufacturer’s instructions. The monohydrate water content was determined to be 1.99%, which is in agreement with the theoretical value of 1.92%.

Literature References:

Reversible dual inhibitor of ErbB1 and ErbB2 tyrosine kinases. Prepn: M. C. Carter et al., WO 9935146(1999 to Glaxo); eidem, US6727256 (2004 to SmithKline Beecham).

Mechanism of action study: W. Xia et al., Oncogene 21, 6255 (2002); and crystal structure in complex with epidermal growth factor receptor (EGFR, ErbB1): E. R. Wood et al., Cancer Res. 64, 6652 (2004).

In vitro antitumor activity in combination with anti-ErbB2 antibodies: W. Xia et al., Oncogene 24, 6213 (2005). Biologic effects on tumor growth: N. L. Spector et al., J. Clin. Oncol. 23, 2502 (2005).

Pharmacokinetics and clinical activity in metastatic carcinomas: H. A. Burris III et al., ibid. 5305.

Review of clinical development: T. E. Kim, J. R. Murren, IDrugs6, 886-893 (2003); H. A. Burris III, Oncologist 9, Suppl. 3, 10-15 (2004).

Lapatinib Ditosylate [USAN]

• Lapatinib ditosylate monohydrate
• Tykerb
• Tyverb
• UNII-G873GX646R
• KS-1300; 388082-78-8

• N-(3-Chloro-4-((3-fluorobenzyl)oxy)phenyl)-6-(5-(((2-(methylsulfonyl)ethyl)amino)methyl)furan-2-yl)quinazolin-4-amine bis(4-methylbenzenesulfonate) monohydrate

Dosages/Routes/Forms

Approval History

In a move that raises questions about the future of drug research in India, Piramal Enterprises will end its drug discovery activities. The decision—which involves possible job losses—will affect several hundred scientists, many of whom were recruited internationally to work in Mumbai in one of India’s most sophisticated pharmaceutical labs.
The company has been considered an Indian leader in drug research since opening its discovery labs in 2004. Within the firm, drug discovery was championed by the vice chairman, Swati A. Piramal, a medical doctor who also holds a master’s degree from the Harvard School of Public Health.
“After reevaluating the risk-benefits of new chemical entity research, the company decided to focus resources on our other areas of R&D with shorter development timelines and different risk profiles,” Piramal tells C&EN.

read all at

http://cen.acs.org/articles/92/i37/Piramal-Drops-Drug-Discovery.html

Piramal Enterprises, which sold off its domestic formulations business to Abbott in a multi-billion dollar deal a few years ago, is now shutting down its Mumbai-based R&D unit which would in effect bring to an end its early stage drug discovery business.

Separate media reports, citing Swati Piramal, part of the promoter group of the diversified firm and wife of group chief Ajay Piramal, said, the decision to move away from the drug discovery business was taken given the costs of basic research.

The company would now focus on molecules at an advanced stage of development; resources would be redeployed from basic research to the clinical unit.

Its other research facilities are located in Chennai, Hyderabad, Ahmedabad and Indore, which would continue to be functional.

Although Piramal Enterprises retains its exposure to healthcare as a sector, after selling the key pharma business, it is now more associated with financial services, including investments in infrastructure and real estate sectors.

In an unrelated development, the firm is forming a joint venture with Navin Fluorine International Limited, an Arvind Mafatlal Group company, to develop, manufacture and sell specialty fluorochemicals with a focus on applications in healthcare, according to a company release.

As per the agreement, Piramal Enterprises will hold 51 per cent of the equity share capital of the proposed joint venture company, whereas the remaining 49 per cent will be held by Navin.

In the first phase of development, the JV is expected to invest around Rs 120 crore in India for this project.

Mumbai-based Navin Fluorine has a turnover of around $100 million. It specialises in specialty fluorine. It had acquired UK-based Manchester Organics, a specialty fluorochemicals research company in 2011.