头孢克肟开环侧链酸的合成

Synthesis of Cefixime Open Side Chain acid

以乙酰乙酸叔丁酯为原料,经过肟化、醚化、氯代酯解反应合成了头孢克肟开环侧链酸。比较了肟化反应不同酸化剂对产品的影响,选用乙酸作酸化剂,醚化反应中用溴乙酸甲酯代替氯乙酸甲酯,氯代酯解反应采取低温反应,硫酰氯与醚化物用量摩尔比为2时,反应总收率为53.4%,高于文献值。

Cefixime open side chain acid was prepared by oximation, etherification, chlorination, ester decomposition using t-butyl acetoacetate as starting material. In the oximation, we compared the effect that various acidifier on the reaction and thought acetic acid is better. In the etherification, we used ethyl bromoacetate instead of ethyl chloroacetate. We carried on the chlorination and ester, decomposition at low temperature and n（sulfuric chloride）：n（ether） was 2. The total yield was 53.4%,which was higher than the literature value.