Antibacterial activity of 6,8-disubstituted-quinolone-3-carboxylic acids

Twelve 6,8-disubstituted-1-ethyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid derivatives were prepared and evaluated for their antibacterial activity. Among these, only the 6,8-difluoroquinolinone-3-carboxylic acid showed moderate activity.