头孢唑啉的合成路线

概述了头孢唑啉的主要合成路线。第一条路线，７－ＡＣＡ（７－氨基头孢烷酸）和噻二唑、四氮唑乙酸反应；第二路线，ＧＣＬＥ先和噻二唑反应，然后脱去３位和７位的保护基团，最后和四氮唑乙酸缩合；第三路线，噻二唑和四氮唑乙酸先形成活性硫醇酯，再与７－ＡＣＡ反应；第四条路线，以噻唑淋－丁啶酮为起始原料进行反应。

Summary about Synthetic Methods of Cefazolin

This article summarizes main methods of synthesising cefazolin. There are four synthesising routes. First route, a beginning material is 7-ACA. 7-ACA reacts with 2-mercapto-5-methylthiadiazole and tetrazole-1-acetic acid. Now it is main method of productive cefazolin. Second route, a beginning material is GCLE. GCLE reacts with 2-mercapto-5-methylthiadiazole. The reactant take off protective groups which lie in 3-place and 7-place. Then the compound reacts with tetrazole-1-acetic acid. This route is newer and good. Third route, 2-mercapto-5-methylthiadiazole and tetrazole-1-acetic acid form active thiol ester. Then the ester reacts with 7-ACA. This method isn't used in produce,bnt it has high yield and less procedure. There is a good prospect. Fourth route,a beginning material is thiazoline-azetidinones. It is in a study stage.