头孢丙烯的合成

Synthesis of Cefprozil

以7-苯乙酰胺基-3-氯甲基-3-头孢烯-4-羧酸二苯甲酯为起始原料,经7-位酰胺基水解、在DCC作用下与侧链D-2-叔丁氧羰基氨基-2-(4-羟苯基)乙酸缩合、3-位氯甲基置换为碘甲基后与三苯膦成内鎓盐,与乙醛进行Wittig反应在3-位形成丙烯基,最后在三氟乙酸作用下脱去7-位侧链氨基和4-位羧基的保护基制得头孢丙烯,总收率16.4%。

Cefprozil was synthesized from benzyhydryl 7-phenylacetamido- 3-chloromethyl-3-cephem-4-carboxylate by hydrolysis, condensation with D-2-(t-butoxycarbonylamino)-2-(p-hydroxyphenyl)acetic acid, conversionof the 3-chloromethyl group to 3-iodomethyl, Wittig reaction with acetaldehyde and hydrolysis with trifluoroacetic acid inan overall yield of 16.4%.