Trifluoromethylmercaptoacetamidocephalosporins

A pharmaceutical composition comprising an antibacterially effective amount of the compound of the formula ##SPC2##

• in which:
• A is S-Het;
• Het is a 5 or 6 membered heterocyclic ring containing 1-4 hetero atoms selected from the group consisting of N, O and S and being unsubstituted or substituted with one or two groups selected from the group consisting of alkyl, alkoxy, alkylthio, each alkyl residue being one to four carbon atoms;
• C.sub.3 -C.sub.4 cycloalkyl, halogen, hydroxy, mercapto, trifluoromethyl and NR.sub.2 ;
• and
• R is hydrogen or C.sub.1 14 C.sub. 6 alkyl, or a pharmaceutically acceptable salt thereof and sterile water or sterile saline as carrier therefor.