Penicillins and cephalosporins and their production

摘要

beta -Lactams of the formula <IMAGE> and pharmaceutically acceptable nontoxic salts thereof wherein A is hydrogen or alkyl of 1 to 4 carbon atoms; B is phenyl, methylphenyl, chlorophenyl, hydroxyphenyl or cyclohexa-1,4-dien-1-yl; R is a moiety of the formula <IMAGE> wherein E is hydrogen, -OH or -O-CO-CH3; and C* constitutes a center of chirality; are produced which exhibit antibiotic activity.