PRODUCTION OF 2-ALKYL-7-SUBSTITUTED-2(OR 3)-CEPHEM-4- CARBOXYLIC ACID

摘要

NEW MATERIAL:A compound of formula I (R1 is amino, acylamino; R2 is alkyl; dotted lines represent 2-cephem or 3-cephem). EXAMPLE:2,2-Trichloroethyl 2-methyl-7-(2-phenylacetamide)-3-cephem-4-carboxylate. USE:Antibacterial, its synthetic intermediate. PREPARATION:A 2-alkyl-7-substituted-2(or 3)-cephem-4-carboxylic acid of formula II, its ester in the carboxyl group or salt is reduced to give the compound of formula I . The compound of formula II as the starting substance is novel and obtained by allowing a Lewis acid to act on a novel compound of formula III, resulting from action of a base on 2-alkyl-2-halomethyl-6-substituted penam-3- carboxylic acid 1-oxide.