title: In vitro studies of semisynthetic alpha-(substituted-ureido) penicillins.
abstract: The activity of three alpha-(substituted-ureido) penicillins was evaluated in vitro against 599 clinical isolates of gram-negative bacilli, by use of the broth-dilution technique. At a concentration of 12.5 mug or less/ml, BL-P1597 inhibited 90% of isolates of Pseudomonas sp., 56% of Enterobacter sp., 67% of indole-positive Proteus spp., 72% of Escherichia coli, and 85% of Proteus mirabilis. BL-P1654 had similar activity, whereas BL-P1532 was much less active. At a concentration of 25 mug or less/ml, BL-P1597 also inhibited nearly 60% of isolates of Klebsiella sp. and nearly 40% of Serratia sp. BL-P1597 and BL-P1654 were as active as ampicillin and carbenicillin against E. coli and P. mirabilis. They were less active than carbenicillin against indole-positive Proteus spp. Both drugs were substantially more active than carbenicillin against Pseudomonas sp. A strain of Pseudomonas sp. which developed resistance to carbenicillin also developed resistance to the alpha-(substituted-ureido) penicillins simultaneously.
mesh_terms: D000362:Agar; D000667:Ampicillin / Q000494:pharmacology; D000818:Animals; D001769:Blood; D002228:Carbenicillin / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D003470:Culture Media; D004754:Enterobacter / Q000187:drug effects* / Q000254:growth & development; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development; D007709:Klebsiella / Q000187:drug effects* / Q000254:growth & development; D008826:Microbial Sensitivity Tests; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology*; D011511:Proteus / Q000187:drug effects* / Q000254:growth & development; D011549:Pseudomonas / Q000187:drug effects* / Q000254:growth & development; D012705:Serratia / Q000187:drug effects* / Q000254:growth & development; D012756:Sheep; D013045:Species Specificity
chemical_list: D003470:Culture Media; D010406:Penicillins; D000667:Ampicillin; D000362:Agar; D002228:Carbenicillin