申请人:Parthasaradhi Bandi
公开号:US20080242858A1
公开(公告)日:2008-10-02
There is provided an improved process for preparing cefixime. Thus, for example, 7-amino-3-vinyl-3-cephem-4-carboxylic acid is reacted with 2-mercapto-1,3-benzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-(methoxycarbonyl)-methoxyimino acetate in tetrahydrofuran and water at 4° C. in the presence of triethylamine. The reaction mass is extracted with ethyl acetate. 7-[2-(2-Amino-4-thiazolyl)-2-(methoxycarbonylmethoxyimino)acetamido]-3-vinyl-3-cephem-4-carboxylic acid triethylamine salt present in the aqueous layer is hydrolyzed with sodium hydroxide in less than 30 minutes and aqueous hydrochloric acid is added immediately to adjust the pH to 4.8 to 5.2. Then, aqueous hydrochloric acid is added at 35° C. to adjust the pH 2.5 and cooled to crystallize cefixime trihydrate in high purity.
提供了一种改进的头孢克肟制备工艺。例如,将7-氨基-3-乙烯基-3-头孢烷-4-羧酸与2-巯基-1,3-苯并噻唑基-(Z)-2-(2-氨基噻唑-4-基)-2-(甲氧羰基)-甲氧基亚乙酸酯在四氢呋喃和水中在三乙胺存在下于4℃反应。反应物质用乙酸乙酯提取。7-[2-(2-氨基-4-噻唑基)-2-(甲氧羰基甲氧基亚乙氧基)亚乙酰氨基]-3-乙烯基-3-头孢烷-4-羧酸三乙胺盐存在于水层中,在不到30分钟内用氢氧化钠水解,并立即加入水盐酸以调节pH值为4.8至5.2。然后,在35℃下加入水盐酸以调节pH值为2.5,并冷却结晶高纯度的头孢克肟三水合物。