DERIVATIVES OF CEPHALOSPORINES AND METHOD FOR THEIR PREPARATION

摘要

Novel derivatives belonging to the group of cephalosporin antibiotics can be obtained by this method for use in controlling the spread of bacterial infections in human and veterinary medicine. The method employs readily procurable raw materials and a reduced number of intermediates. The derivatives have the following general formula:<IMAGE>where A = H or<IMAGE>The derivatives are obtained by means of N-acylation of substituted, respectively, at the meanings of A, 7-amino-3-cephem-4-carboxylic acid, with a mixed anhydride obtained from 5-acetyl-2,4-dimethyl-5-carboxypyrol and alkyl chloroformate.