| Abstract: | Two optically active isomers of 1-ethyl-6,8-difluoro-1,4-dihydro-7-(3-hydroxypyrrolidin-1-yl)-4-oxoquinoline-3-carboxylic acid ( 10 ) were prepared. One of the isomer, 7-(3S)-hydroxypyrrolidin-1-yl] derivative 8 , was about 4 times more potent in vitro than the other, 7-(3R)-hydroxypyrrolidin-1-yl] derivative 4 , and approximately two times more active than the racemate, 7-(3RS)-hydroxypyrrolidine-1-yl] derivative 10. Optical active 8 was the most active in in vivo, followed by 10 , and 4 was the least active compound. But, they were more potent than CI-934 12 and norfloxacin. From the results, (3S)-hydroxypyrrolidinyl group was found to be one of the beneficial group for PCA-anti-bacterial agent. |
