1-Cyclopropyl-6,7-difluoro-8-methoxy-4-oxo-3-quinolinecarboxylic acid

1-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid

1-Cyclopropyl-6,7-difluoro-8-methoxy-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid