BMY28142, cefbuperazone (T-1982), and Sch 34343. Antimicrobial activity against 94 anaerobes compared to seven other antimicrobial agents.

Three new beta-lactams were evaluated against 94 anaerobic strains representing 15 species using a Wilkins-Chalgren broth microdilution method. The penems, Sch 29482 and Sch 34343, were most active with all minimum inhibitory concentrations (MICs) at less than or equal to 4.0 micrograms/ml and MIC90s of less than or equal to 0.25 micrograms/ml. BMY 28142 had a more limited antianaerobic activity against Bacteroides fragilis with a MIC50 and MIC90 of 32 and 128 micrograms/ml, respectively. Cefbuperazone (T-1982) had low B. fragilis MICs (MIC90, 8.0 micrograms/ml), but potentially resistant range MIC90 results for the other species in the B. fragilis group and Clostridium species.