New thioloesters of the formula: ##STR1## wherein R.degree. represents hydrogen, alkyl, vinyl, cyanomethyl or a protecting radical, R' represents hydrogen or a protecting radical, R represents alkyl, L-2-amino-2-carboxyethyl, phenyl or various heterocyclic radicals, and their syn and anti isomers and mixtures thereof, and metal salts thereof and addition salts thereof with tertiary nitrogen-containing bases, are intermediates useful in the preparation of cephalosporins having anti-bacterial properties.
新的巯酯的
化学式为:##STR1## 其中 R.degree. 代表氢、烷基、
乙烯基、
氰甲基或保护基,R' 代表氢或保护基,R 代表烷基,
L-2-
氨基-2-羧乙基、苯基或各种杂环基,以及它们的syn和anti异构体及其混合物,以及它们的
金属盐和与含有三级氮的碱形成的加合盐,是制备具有抗菌性能的
头孢菌素的中间体。