CAS: 70374-36-6; 5-Chloro-3-(N-Methylsulfamoyl)Thiophene-2-Carboxylic Acid

专利信息

专利号:US-11697658-B2
优先权日:2020-12-25
标题:Method for preparing lornoxicam
发明人：LIU ZHEN; XING DONGYE; ZHANG ZHONGZHENG; LI JIE; Han Yangong; CUI YALI; WANG LIRU; LIU HONGLIANG; MI YAN; LI LI; TANG JINGANG; KANG YI
权利人:BEIJING JINCHENG TAIER PHARMACEUTICAL CO LTD
摘要:The present disclosure relates to the technical field of drug synthesis, in particular to a method for preparing lornoxicam. The method includes the following steps: using 6-chloro-4-hydroxy-2-methyl-2-H-thieno[2,3-e]-1,2-thiazine methyl carboxylate-1,1-dioxide and 2-aminopyridine as raw materials, and xylene as a solvent; mixing the raw material and solvent, and adding a stabilizer, to obtain a mixture; subjecting the mixture to an ammonolysis; cooling the resulting reactant; conducting a vacuum concentration to remove the solvent; adding an organic solvent and slurrying, and filtering, to obtain a crude lornoxicam; and refining the crude lornoxicam to obtain the lornoxicam. In the present disclosure, p-toluenesulfonic acid is used as a stabilizer to reduce the reaction temperature and promote the reaction to proceed forward, thereby improving the quality and yield of the product.