Chin N X, Neu H C
Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York 10032.
Antimicrob Agents Chemother. 1988 May;32(5):671-7. doi: 10.1128/AAC.32.5.671.
The in vitro activity of R-3746, an iminomethoxy aminothiazolyl cephalosporin with a CH2OCH3 moiety at position 3, was compared with those of other antibiotics. R-3746 inhibited the majority of hemolytic streptococci (groups A, B, C, F, and G) and Streptococcus pneumoniae at less than 0.06 micrograms/ml, which was comparable to the activity of amoxicillin, 2- to 8-fold more active than cefixime, and 16- to 64-fold more active than cefaclor and cephalexin. Ninety percent of beta-lactamase-producing Haemophilus influenzae and Neisseria gonorrhoeae were inhibited at a concentration 0.25 micrograms/ml, but it was less active against Branhamella spp. It did not inhibit (MIC, greater than 16 micrograms/ml) enterococci, viridans group streptococci, or methicillin-resistant staphylococci. The MICs of R-3746 for 90% of strains tested for Escherichia coli; Klebsiella pneumoniae; Citrobacter diversus; Proteus mirabilis; and Salmonella, Shigella, and Yersinia spp. were less than or equal to 1 micrograms/ml. It was two- to eightfold less active than cefixime but was markedly superior to cefaclor, cephalexin, amoxicillin-clavulanate, and trimethoprimsulfamethoxazole. R-3746 inhibited 50% of Enterobacter cloacae, Enterobacter aerogenes, Citrobacter freundii, Morganella spp., Providencia spp., Proteus vulgaris, and Serratia marcescens at less than or equal to 8 micrograms/ml. Pseudomonas spp. were resistant. Fifty percent of Clostridium spp. were inhibited by 0.5 micrograms/ml, but MICs for Bacteroides spp. were greater than 128 micrograms/ml. R-3746 was not appreciably hydrolyzed by most chromosomal and plasmid-mediated beta-lactamases.
将在3位带有CH2OCH3基团的亚氨基甲氧基氨基噻唑基头孢菌素R-3746的体外活性与其他抗生素进行了比较。R-3746对大多数溶血性链球菌（A、B、C、F和G组）和肺炎链球菌的抑制浓度低于0.06微克/毫升，这与阿莫西林的活性相当，比头孢克肟活性高2至8倍，比头孢克洛和头孢氨苄活性高16至64倍。90%产β-内酰胺酶的流感嗜血杆菌和淋病奈瑟菌在浓度为0.25微克/毫升时受到抑制，但对布兰汉菌属活性较低。它不抑制（最低抑菌浓度，大于16微克/毫升）肠球菌、草绿色链球菌或耐甲氧西林葡萄球菌。R-3746对90%受试的大肠杆菌、肺炎克雷伯菌、异型枸橼酸杆菌、奇异变形杆菌以及沙门菌属、志贺菌属和耶尔森菌属菌株的最低抑菌浓度小于或等于1微克/毫升。它比头孢克肟活性低2至8倍，但明显优于头孢克洛、头孢氨苄、阿莫西林-克拉维酸和甲氧苄啶-磺胺甲恶唑。R-3746在小于或等于8微克/毫升时抑制50%的阴沟肠杆菌、产气肠杆菌、弗氏枸橼酸杆菌、摩根菌属、普罗威登斯菌属、普通变形杆菌和粘质沙雷菌。铜绿假单胞菌属耐药。50%的梭菌属在0.5微克/毫升时受到抑制，但对拟杆菌属的最低抑菌浓度大于128微克/毫升。R-3746不会被大多数染色体介导和质粒介导的β-内酰胺酶明显水解。
