Process for the preparation of new penicillins and of new cephalosporins

摘要

The compounds of formula Ia are prepared by reaction of an iminoether of formula II with a reactive derivative of the carboxyl group of a compound of formula III and subsequent hydrolysis in order to remove the group . During the hydrolysis, certain protective groups R<7> are already split off. In the formulae, the symbols have the meaning given in Claim 1. According to another process, the compound of formula Ia is first prepared by the route shown and the protective group R<7> is then removed. The compounds obtained are useful as antibacterial medicaments.