3-heterocyclic substituted cephem compounds

Abstract

Novel cephem compounds having a group of the formula at the 3-position thereof: ##STR1## wherein X represents oxygen, sulfur or imino, which may be substituted; and B represents hydrogen or a hydroxyl, amino, mercapto or hydrocarbon group, which groups may be substituted, can be prepared by reacting a 3-formylcephem compound with a hydrazine compound of the formula: ##STR2## wherein the symbols have the same meanings as above, and subjecting the thus obtained compound to an oxidative ring-closure reaction. The objective compounds are found to have a broad antimicrobial spectrum and, in particular, are effective against gram-negative bacteria including Escherichia Coli, Klebsiella pneumoniae, Proteus vulgaris, Proteus mirabilis, Proteus rettgerii, as well as gram positive ones, and have low-toxity. Thus, these compounds may be used for antimicrobial agents in therapeutical purpose.