一二三四区视频,亚洲少妇熟女色,日本久热无码视频网,欧美国产日韩大尺度,亚洲a视频,久久少妇一区二区,日韩999无码视频,刺激久久久久久久,啊啊啊啊不要啊在线

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
010-86108875
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List Parecoxib
198470-84-7

Parecoxib synthesis

9synthesis methods
Propionic anhydride

123-62-6

Valdecoxib

181695-72-7

Parecoxib

198470-84-7

General procedure for the synthesis of N-((4-(5-methyl-3-phenylisoxazol-4-yl)phenyl)sulfonyl)propionamide from propionic anhydride and 4-(5-methyl-3-phenyl-1,2-oxazol-4-yl)benzenesulfonamide: 3.1 grams (10 mmol) of 4-(5-methyl-3-phenyl-1,2-oxazol-4-yl)benzenesulfonamide was mixed with 3.5 grams (35 mmol) of triethylamine and 2.6 g (20 mmol) propionic anhydride in 20 mL of chloromethane. After completion of the reaction, the reaction mixture was poured into water and extracted with dichloromethane. The extract was concentrated, dissolved in ethanol, crystallized 5 to 10 times, filtered and dried to give 3.4 g of N-((4-(5-methyl-3-phenylisoxazol-4-yl)phenyl)sulfonyl)propionamide in 92.5% yield and 99.77% purity.

-

Yield:198470-84-7 97.7%

Reaction Conditions:

with benzenesulfonic acid at 50; for 2 h;Reagent/catalyst;Temperature;

Steps:

1.3; 2.3; 3.3; 4.3; 5.3 3. Preparation of parecoxib (formula 4 compound)
Weighed 15g (47.7mmol, 1e.q) of valdecoxib (compound of formula 3),Add to 22.5ml of propionic anhydride (238.5mmol, 5e.q), stir and heat to raise the temperature to 50 ° C,Add 0.076 g (4.8 mmol, 0.1 e.q) benzenesulfonic acid, react for 120 minutes, and cool to room temperature (15-30 ° C).Crystallization, filtration, vacuum drying at 55±5°C, vacuum degree -0.070-0.082Mpa for 4-6h,17.27 g of parecoxib was obtained, the yield was 97.7%, and the purity was 99.9% by HPLC.

References:

Kunyao Group Co., Ltd.;Xi Liang;Zhu Changcheng;Jin Yi;Ba Dewei;Wen Na;Hu Yanchao CN110256370, 2019, A Location in patent:Paragraph 0043; 0048-0049; 0052; 0057-0058; 0061; 0066-0067

FullText

Parecoxib Related Search:

宁河县| 石屏县| 长子县| 景宁| 望谟县| 闽侯县| 永康市| 西贡区| 肃北| 绵阳市| 三穗县| 沭阳县| 黄骅市| 惠州市| 砀山县| 砚山县| 石屏县| 任丘市| 华蓥市| 晋江市| 哈密市| 广宁县| 榕江县| 根河市| 驻马店市| 来凤县| 塔河县| 巴东县| 楚雄市| 本溪| 若尔盖县| 伊宁市| 泾源县| 巴塘县| 巴中市| 永寿县| 瑞丽市| 岳阳县| 施甸县| 东莞市| 潼南县|