108115-66-8Relevant academic research and scientific papers
Synthesis of [1-15N,2-13C]-labeled difloxacin
Schmidt, Burkhard,Schumacher-Buffel, Ramona,Thiede, Brigitte,Schaeffer, Andreas
experimental part, p. 1221 - 1227 (2011/10/02)
The synthesis of [1-15N,2-13C]-difloxacin, an arylfluoroquinolone antibacterial agent, is reported. As a crucial initial step, the starting materials ethyl 2,4,5-trifluorobenzoylacetate, [formyl- 13C]-triethyl orthoformate, and [15N]-4-fluoroaniline were reacted to ethyl [15N,3-13C]-3-(4-fluoroanilino)-2-(2,4, 5-trifluorobenzoyl)acrylate. After cyclization and ester cleavage, the resulting intermediate was reacted with 1-methylpiperazine to [1-15N,2- 13C]-1-(4-fluorophenyl)-6-fluoro-7-(4-methyl-1-piperazinyl)-1, 4-dihydro-4-oxoquinoline-3-carboxylate, i.e., [1-15N,2- 13C]-difloxacin. The overall yield was 62% based on the non-labeled and 43% based on the labeled starting materials (both used in 1.4 molar excess). The product was identified by 1H-, 13C-, and 15N-NMR spectroscopy and by cochromatography (TLC, HPLC) with an authentic reference; its purity (HPLC) was above 98%. Prior to synthesis of [1-15N,2-13C]-difloxacin, non-labeled difloxacin was synthesized in order to optimize procedures and to identify and characterize all intermediates.
Effect of Lipophilicity at N-1 on Activity of Fluoroquinolones against Mycobacteria
Renau, Thomas E.,Sanchez, Joseph P.,Shapiro, Martin A.,Dever, Julie A.,Gracheck, Stephen J.,Domagala, John M.
, p. 2974 - 2977 (2007/10/02)
The dramatic increase in drug resistant Mycobacterium tuberculosis has caused a resurgence in research targeted toward these organisms.As part of a systematic study to optimize the quinolone antibacterials against mycobacteria, we have prepared a series of N-1-phenyl-substituted derivatives to explore the effect of increasing lipophilicity on potency at this position.The compounds, synthesized by the modification of a literature procedure, were evaluated for activity against Gram-negative and Gram-positive bacteria, Mycobacterium fortuitum and Mycobacterium smegmatis, and the results correlated with log P, pKa, and other attributes.The activity of the compounds against the rapidly growing, less hazardous organism M. fortuitum was used as a measure of M. tuberculosis activity.The results demonstrate that increasing lipophilic character by itself does not correlate with increased potency against mycobacteria.Rather, intrinsic activity against Gram-negative and/or Gram-positive bacteria is the governing factor for corresponding activity against mycobacteria.
