4-(Tetrazol-5-yl)-.DELTA..sup.3 -cephem compounds

A compound selected from the group consisting of ##STR92## the acid addition salts thereof when R is hydrogen and the base addition salts thereof when R.sub.1 and R.sub.11 are hydrogen;

• said R being selected from the group consisting of hydrogen and ##STR93## wherein R.sub.3, R.sub.4 and R.sub.5 are each selected from the group consisting of hydrogen, chloro, bromo, fluoro, methyl, methoxy and phenyl;
• A being selected from the group consisting of hydrogen and acetoxy;
• R.sub.1 being selected from the group consisting of hydrogen, alkanoyloxymethyl having from three to six carbon atoms, 1-(alkanoyloxy)ethyl having from four to seven carbon atoms, methoxymethyl, and phthalidyl
• and R.sub.11 being selected from the group consisting of hydrogen, alkanoyloxymethyl having from three to six carbon atoms, 1-(alkanoyloxy)ethyl having from four to seven carbon atoms, methoxymethyl, phthalidyl, ##STR94## wherein R.sub.6 is selected from the group consisting of alkyl having from one to three carbon atoms and phenyl and R.sub.7 is selected from the group consisting of hydroxy, methoxy, alkanoyloxy having two or four carbon atoms, and benzyloxy and R.sub.8 is selected from the group consisting of hydrogen, hydroxy, fluoro, chloro, bromo, iodo, methyl, methoxy, alkanoyloxy having from two to four carbon atoms, phenyl and benzyloxy and ##STR95## wherein R.sub.9 and R.sub.10 are each selected from the group consisting of hydrogen and methyl and X is selected from the group consisting of oxygen and sulfur.