A cephalosporin antibiotic; active against clinical isolates of extended-spectrum β-lactamase-producing E. coli, K. pneumoniae, and P. mirabilis, as well as C. freundii, E. aerogenes, E. cloacae, S. marcescens, and P. vulgaris; protective against lethality in mouse models of systemic infection induced by various bacteria (ED50s = ≤0.025-1.56 mg/kg); reduces the number of renal CFUs in a mouse model of S. epidermidis-induced ascending pyelonephritis at 50 mg/kg