COMPARATIVE ACTIVITIES OF NOVEL BETA-LACTAMASE INHIBITORS, 6-EXOMETHYLENE PENAMSULFONES (CH1240, CH2140) IN EXPERIMENTAL MOUSE INFECTION MODEL

The antibacterial activity oi novel p-lactamase inhibitors, 6-exomethy lene penamsulfones (CH 1240, CH2140), has been compared in vivo with t hat of sulbactam and clavulanic acid against p-lactamase producing str ains, in vivo microbiological assessment was used as experimental mous e infection model by gram negative strains. Against Pseudomonas aerugi nosa F0013, cefoperazone/CH1240 was slightly less active than sulbacta m. Ampicillin/CH 1240 was more active than sulbactam against Citrobact er diversus species. That oi ampicillin/CH 2140 was less effective tha n sulbactam against Escheriachia coli 3457. Especially against Citroba cter diversus 2046E, amoxicillin/CH 2140 was the most potent and amoxi cillin/CH1240 was slightly more active than clavulanic acid. Consequen tly the difference in efficacy between the drug combinations appears t o be related to the degree oi protection afforded the animals by the P lactamase inhibitors. CH1240 and CH2140 are promising new agents and s hould undergo further investigations.