New cephalosporins and 7 alpha-methoxy cephalosporins. Chemistry and biological activities.

The synthesis and the in vitro activity of a number of cephalosporins and 7 alpha-methoxy cephalosporins having 7-acyl substituents derived from 1-methyl-4 (or 5)-nitro-1H-imidazolyl-thioacetic acids are described. The microbiological profile is influenced by the position of both the nitro group and the side-chain sulfur atom on the 1-methyl imidazole, and by the nature of the 3-substituent.