Asymmetric Synthesis and Properties of the Enantiomers of the Antibacterial Agent 7-(3-Aminopyrrolidin-1-yl)-1-(2,4-difluorophenyl)-1,4-dihydro-6-fluoro-4-oxo-1,8-naphthyridine-3-carboxylic Acid Hydrochloride

Article abstract of DOI:10.1021/jm00403a017

Compound 1 <7-(3-aminopyrrolidin-1-yl)-1-(2,4-difluorophenyl)-1,4-dihydro-6-fluoro-4-oxo-1,8-naphthyridine-3-carboxylic acid hydrochloride> is a potent member of the quinoloecarboxylic acid class of antibacterial agents and is currently undergoing clinical evaluation.We have developed efficient asymmetric syntheses of the enantiomers of this agent.The S-(+) enantiomer 1a is 1-2 log₂ dilutions more active than the R-(-) enantiomer 1b against aerobic bacteria and 1-2 or more log₂ dilutions more active against anaerobic bacteria in vitro.The enantiomer 1a shows significantly better in vivo activity in a Pseudomonas aeruginosa mouse protection model compared to racemic 1.Coupled with the improved solubility profile of 1a relative to racemic material, these features may be of practical significance from a clinical standpoint.