azlocillin and mezlocillin ( mic for 90 % of isolates , 0.78 micrograms/ml ) and piperacillin , ampicillin , and vancomycin ( mic for 90 % of isolates , 1.56 micrograms/ml ) were the most active agents and were significantly more potent than the other reference antibiotics tested .
C0025893
mezlocillin
C0002680
ampicillin