A cephalosporin antibiotic; active against numerous Gram-negative bacteria, including strains of P. mirabilis, P. vulgaris, E. coli, S. typhimurium, and S. enteritidis (MICs = 4-32 UG/ml for all); binds to B. subtilis PBP2a, -2b, -3, -4, and -5 (IC50s = 0.72, 0.19, 1.04, 0.14, and 0.19 UG/ml, respectively); increases survival in mice infected with S. aureus, S. pyogenes, or K. pneumoniae (ED50s = 250, 63, and 795 UG/animal, respectively)