NS 398 is a COX-2 inhibitor used in the study of the function of cyclooxygenases.

NS 398

N-[2-(Cyclohexyloxy)-4-nitrophenyl]methanesulfonamide

Taisho (Originator)

Taisho Pharmaceutical Co. Ltd

N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide.

123653-11-2, 123653-43-0 (Ca salt), 123653-44-1 (Na salt)

Cerebrovascular Diseases, Treatment of, NEUROLOGIC DRUGS, Stroke, Treatment of, Cyclooxygenase-2 Inhibitors

NS-398 is a COX-2 inhibitor used in the study of the function of cyclooxygenases.^[2]

Selective cyclooxygenase-2 inhibitor (IC₅₀ values are 3.8 and > 100 μM for COX-2 and COX-1 respectively). Orally active. Anti-inflammatory, anti-pyretic, analgesic and non-ulcerogenic in vivo. Induces apoptosis and cell cycle arrest

Cyclooxygenase (COX-2) has been recently suggested to play a role in hepatocarcinogenesis. However, the exact pathway by which COX-2 affects the growth of hepatocellular carcinoma (HCC) is not clear. This study investigated the effects of a specific COX-2 inhibitor, NS-398, on the cell proliferation and apoptosis of COX-2-expressing and non-expressing HCC cell lines.

In addition, the modulatory effect of NS-398 on apoptosis-regulating gene expression was examined. Semi-quantitative/quantitative reverse transcription-polymerase chain reaction and Western blot showed that Hep3B and HKCI-4 cells expressed COX-2 mRNA and protein, but HepG2 cells did not. NS-398 suppressed cell proliferation and induced apoptosis in the two COX-2-expressing cell lines in a dose-dependent manner, but not in HepG2 cells.

Fas ligand mRNA and protein expression were increased by the treatment with NS-398 (10 micro M) in COX-2-expressing cell lines. The expressions of Fas and Bcl-2 family genes (Bax, Bcl-2, Bcl-xL, Bcl-xS) were not affected by NS-398 treatment in all three cell lines. In conclusion, specific COX-2 inhibitor suppresses cell proliferation and induces apoptosis in HCC cell lines that express COX-2. Our finding suggests that COX-2 inhibition may offer a new approach for HCC chemoprevention.

IUPAC name N-[2-(Cyclohexyloxy)-4-nitrophenyl]methanesulfonamide
Identifiers
CAS number	123653-11-2
PubChem	4553
Jmol-3D images	Image 1
SMILES [show]
Properties
Molecular formula	C13H18N2O5S
Molar mass	314.36 g mol−1
Appearance	Off-white solid
Solubility in water	Insoluble
Solubility in DMSO	5 mg/mL
Hazards
S-phrases	S22 S24/25

The condensation of 2-fluoronitrobenzene (I) with cyclohexanol (II) by means of NaH gives 2-(cyclohexyloxy)nitrobenzene (III), which is reduced with H2 over Pd/C in methanol yielding 2-(cyclohexyloxy)aniline (IV). The acylation of (IV) with methanesulfonyl chloride (V) in pyridine affords N-(2-cyclohexyloxy phenyl)methanesulfonamide (VI), which is finally nitrated with concentrated HNO3 in hot acetic acid.

EP 0317332

http://www.google.com/patents/EP0317332A2?cl=en

Example 1
• [0045]
  (1) To 40 ml of a dioxane suspension containing 0.92 g of 60% sodium hydride was added 2.5 ml of cyclo­hexanol at room temperature over a 15-minute period, and the mixture was stirred at the same temperature for 1 hour and then at 50°C for 3.5 hours. The temperature of the reaction solution was returned to room temperature, 10 ml of a dioxane containing 3.2 g of 2-fluoro­nitrobenzene was added dropwise, and the mixture was stirred at room temperature overnight. The dioxane was evaporated, the residue was extracted with chloroform, and the chloroform layer was washed, in turn, with water and a saturated aqueous sodium chloride solution and then dried over anhydrous sodium sulfate. The solvent was evaporated to give an oil, which was then distilled under reduced pressure to give 3.8 g of 2-cyclohexyloxy­nitrobenzene.
  b.p. 130 – 134°C/0.5 – 0.7 mmHg
• [0046]
  (2) Fifty ml of a methanol solution containing 3.7 g of 2-cyclohexyloxynitrobenzene and 0.2 g of 5% palladium on carbon was stirred at room temperature under a hydrogen atmosphere for catalytic reduction. The catalyst was removed by filtration, and the filtrate was evaporated off to give 2.9 g of 2-cyclo­hexyloxyaniline as pale brown crystals.
  m.p. 55 – 56°C
• [0047]
  (3) To 20 ml of a pyridine solution containing 2.7 g of 2-cyclohexyloxyaniline was added dropwise 1.8 g of methanesulfonyl chloride under ice cooling with stir­ring. After completion of the addition, the mixture was stirred at room temperature for 2 hours. The reaction solution was poured into ice water and made acidic with dilute hydrochloric acid. The crystals which formed were collected by filtration, washed with water and dried to give 3.8 g of the crude crystals, which were then recrystallized from ethanol-n hexane to give 3.4 g of N-(2-cyclohexyloxyphenyl)methanesulfonamide.
  m.p. 113 – 115°C
• [0048]
  (4) To 20 ml of an acetic acid solution containing 3.4 g of N-(2-cyclohexyloxyphenyl)methanesulfonamide was added dropwise 1.5 g of 61% nitric acid on heating at 110°C over a 30-minute period, and then the mixture was stirred for 1 hour. The reaction solution was poured into ice water and neutralized with a dilute aqueous sodium hydroxide solution. The crystals which formed were collected by filtration, washed with water and dried to give 4.5 g of the crude crystals, which were then recrystallized from ethanol-n-hexane to give 3.3 g of N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide.
  m.p. 136 – 137°C

The cortical collecting duct (CCD) is a major site of intrarenal prostaglandin E₂ (PGE₂) synthesis. This study examines the expression and regulation of the prostaglandin synthesizing enzymes cyclooxygenase-1 (COX-1) and -2 in the CCD. By indirect immunofluorescence using isoform-specific antibodies, COX-1 and -2 immunoreactivity was localized to all cell types of the murine M-1 CCD cell line. By immunohistochemistry, both COX-1 and COX-2 were localized to intercalated cells of the CCD on paraffin-embedded mouse kidney sections. When COX enzyme activity was measured in the M-1 cells, both indomethacin (COX-1 and -2 inhibitor) and the specific COX-2 inhibitor NS-398 effectively blocked PGE₂ synthesis. These results demonstrate that COX-2 is the major contributor to the pool of PGE₂synthesized by the CCD. By Western blot analysis, COX-2 expression was significantly upregulated by incubation with either indomethacin or NS-398. These drugs did not affect COX-1 protein expression. Evaluation of COX-2 mRNA expression by Northern blot analysis after NS-398 treatment demonstrated that the COX-2 protein upregulation occurred independently of any change in COX-2 mRNA expression. These studies have for the first time localized COX-2 to the CCD and provided evidence that the intercalated cells of the CCD express both COX-1 and COX-2. The results also demonstrate that constitutively expressed COX-2 is the major COX isoform contributing to PGE₂synthesis by the M-1 CCD cell line. Inhibition of COX-2 activity in the M-1 cell line results in an upregulation of COX-2 protein expression.

http://jasn.asnjournals.org/content/10/11/2261.abstract
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NS398 inhibits the growth of OSCC cells by mechanisms that are dependent and independent of suppression of PGE₂ synthesis. Molecular targeting of COX-2, PGE₂ synthase, or PGE₂ receptors may be useful as a chemopreventive or therapeutic strategy for oral cancer.

http://clincancerres.aacrjournals.org/content/9/5/1885.full

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References