title: Comparison of the in vitro activity of Bay k 4999 and piperacillin, two new antipseudomonal broad-spectrum penicillins, with other beta-lactam drugs.
abstract: Bay k 4999 and piperacillin, two new substituted ampicillins, were compared with other beta-lactam antibiotics, including carbenicillin, azlocillin, mezlocillin, benzylpenicillin, ampicillin, and cefoxitin, against a wide range of gram-positive and -negative organisms. Bay k 4999 and piperacillin were extremely active against Pseudomonas aeruginosa (50% inhibited by 2 mug/ml), being about 16-fold more active than carbenicillin. Bay k 4999 was the most active drug against Escherichia coli (50% inhibited by 0.5 mug/ml) and Klebsiella spp. (50% inhibited by 2 mug/ml). Piperacillin and Bay k 4999 were equally active against Proteus spp., and piperacillin had high activity against Bacteroides fragilis (50% inhibited by between 1 and 2 mug/ml).
mesh_terms: D001390:Azlocillin / Q000031:analogs & derivatives; D001419:Bacteria / Q000187:drug effects*; D001441:Bacteroides fragilis / Q000187:drug effects; D002440:Cefoxitin / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects; D006193:Haemophilus influenzae / Q000187:drug effects; D048289:Imidazolidines; D009344:Neisseria gonorrhoeae / Q000187:drug effects; D010406:Penicillins / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects; D013291:Streptococcus / Q000187:drug effects
chemical_list: D002511:Cephalosporins; D048289:Imidazolidines; D010406:Penicillins; D002440:Cefoxitin; D001390:Azlocillin; C017976:furazlocillin