cefoxitin and moxalactam were the only agents stable to all chromosomal beta-lactamases , whereas cefamandole , cefoperazone , cefotaxime , carbenicillin , and piperacillin were destroyed by cephalosporinases of proteus vulgaris and bacteroides fragilis .
C0007541
cefamandole
C0007552
cefoperazone