A β-lactam cephalosporin antibiotic; inhibits the growth of various Gram-positive and Gram-negative bacteria, including several strains of S. pyogenes, S. aureus, C. tetani, N. gonorrhoeae, Salmonella, and Shigella (MICs = 0.1-0.2, 0.312-0.625, 0.078, 1.25, 1.56-6.25, and 3.12-12.5 μg/ml, respectively); binds to E. coli PBPs (IC50s = S. pyogenes, D. pneumoniae, and S. aureus