Synthesis and Antibacterial Activities of Optically Active Substituted 1, 2-Dihydro-6-oxo-6H-pyrrolo[3, 2, 1-ij]quinoline-5-carboxylic Acids

A series of optically active substituted 1, 2-dihydro-6-oxo-pyrrolo[3, 2, 1-ij]quinoline-5-carboxylic acids was prepared via optically active 2-methyl-4, 5-difluoroindoline (10) and tested for antibacterial activities. Among them, (2S)-9-[(3R, 1'S)-3-(1'-amino)ethyl-1-pyrrolidinyl]-8-fluoro-1, 2-dihydro-2-methyl-6-oxo-6H-pyrrolo[3, 2, 1, -ij]-quinoline-5-carboxylic acid (19) showed potent activity against gram-positive bacteria and (2S)-8-fluoro-1, 2-dihydro-2-methyl-9-(3-methyl-1-piperazinyl)-6-oxo-6H-pyrrolo[3, 2, 1-ij]quinoline-5-carboxylic acid (16) exhibited well balanced in vitro activity, good intravenous efficacy, and high aqueous solubility.