Synthesis and in vitro antibacterial activity of fluoroquinolone derivatives containing 3-(N′-alkoxycarbamimidoyl)-4-(alkoxyimino) pyrrolidines

A series of novel 7-[3-(N'-alkoxycarbamimidoyl)-4-(alkoxyimino)pyrrolidin-1-yl] fluoroquinolone derivatives were designed, synthesized and characterized by H-1 NMR, MS and HRMS. These fluoroquinolones were screened for their in vitro antibacterial activity. Most of them exhibit good potency in inhibiting the growth of Staphylococcus aureus and Staphylococcus epidermidis (MIC: 0.06-4.00 mu g/mL). The activity of compounds 33 and 43 against S. aureus including MRSA and S. epidermidis including MRSE (MIC: 0.06-0.125 mu g/mL) is more than or comparable to the reference drugs levofloxacin and gemifloxacin. In addition, compound 33 is 32 and 16-32 fold more potent than both the reference drugs against Enterococcus faecium 08-7 and Klebsiella pneumoniae 09-22, respectively. (C) 2010 Elsevier Masson SAS. All rights reserved.