Lefucoxib (乐福昔布)

Lefucoxib (乐福昔布)
5-(3,4-dimethyl-phenyl)-1-methanesulfonyl-3-trifluoromethol-pyrazole
1 [4- (methylsulfonyl) phenyl] -3-trifluoromethyl-5- (3,4-dimethylphenyl) - pyrazole
CAS 849048-84-6
394.411, C19 H17 F3 N2 O2 S
IND FILED
Prostaglandin G/H Synthase 2 (PTGS2; COX-2) Inhibitors
A COX-2 inhibitor potentially for the treatment of rheumatoid arthritis.
cyclooxygenase-2 (COX-2) inhibitor
National Center of Biomedical Analysis

冉允章, 梅世昌

梅世昌, 冉允章

CHINA FLAG

PATENT

CN 1468854

http://www.google.com/patents/CN1468854A?cl=en

Example 1
1 [4- (methylsulfonyl) phenyl] -3-trifluoromethyl-5- (3,4-dimethylphenyl) - pyrazole (I1)
1- (3,4- two toluene-yl) -4,4,4-trifluoro-methyl - D-1,3-dione (IV1) of sodium metal was weighed 2.3g (0.1mol) was added 50ml of anhydrous toluene to prepare a sodium sand. After cooling, ethanol was added dropwise 12ml, and then heated at 60 ℃, complete reaction of sodium metal. After cooling to room temperature, was added 3,4-dimethylphenyl ethanone 23.8g (0.1mol) and trifluoroacetic ethyl acetate 20ml (0.2mol), reacted at 100 ℃ 5 hours. Toluene was distilled off under reduced pressure, a 10% aqueous hydrochloric acid was added, the pH was adjusted to 2-3, extracted with ethyl acetate, washed with water, dried over anhydrous MgSO4, ethyl acetate was distilled off under reduced pressure. Then under reduced pressure, distillation, collecting fractions 105-107 ℃ / 0.7mmHg, was 14.6g, 60% yield.
1- [4- (methylsulfonyl) phenyl] -3-trifluoromethyl-5- (3,4-dimethylphenyl) - pyrazole (I1) take the above-prepared substituted (IV1) 2.38g (0.01mol ), 15ml of ethanol, then added p-methanesulfonyl phenyl hydrazine salt alkoxide 2.3g (0.01ml). Was refluxed for 15 hours. Place the refrigerator overnight, the crystals were collected by filtration, recrystallized from ethanol, mp 129-31 ℃, to give 3.1 g.
Elemental analysis: C19H17F3N2O2S Calculated: C, 57.86; H, 4.34; N, 7.10 Found: C, 57.97; H, 4.29; N, 7.20MS (m / z): 395 (M + 1)

References

Cheng, Feixiong, Edited by Lee, Philip W, From Handbook of Metabolic Pathways of Xenobiotics (2014), 4, 1655-1656

Bi, X.; Meng, Z.; Chen, H.; Zhu, X.; Dou, G.
In vivo and in vitro metabolism of lefucoxib in rats, J Pharm Biomed Anal. 2008 Sep 10;48(1):134-9. doi: 10.1016/j.jpba.2008.04.024. Epub 2008 Apr 30.

Bi, X.; Meng, Z.; Dou, G.   Determination of lefucoxib in rat plasma, urine, and feces by high-performance liquid chromatography with fluorescence detection: Application in pharmacokinetic studies
J Chromatogr B Anal Technol Biomed Life Sci 2007, 850(1-2): 199

Talanta (2011), 85(1), 8-27

Jiefangjun Yaoxue Xuebao (2009), 25(6), 496-498.

Yaowu Fenxi Zazhi (2006), 26(9), 1222-1224.

Zhongguo Yaolixue Yu Dulixue Zazhi (2007), 21(2), 147-151.

CN101497585B

Jan 31, 2008

Jan 12, 2011

中国科学院理化技术研究所

Method for photocatalytic synthesis of 1,3,5-trisubstituted-2-pyrazole derivative

China PLA General Hospital

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