ethyl 1-methyl-6-nitro-7-[4-(2-pyridyl)-1-piperazinyl]-4-oxo-1,4-dihydroquinoline-3-carboxylate

6-Amino-1-cyclopropyl-7-(4-hydroxy-piperidin-1-yl)-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid ethyl ester

6-Amino-1-cyclopropyl-7-(3-methyl-piperazin-1-yl)-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid ethyl ester

7-Chloro-6-nitro-4-oxo-1-o-tolyl-1,4-dihydro-quinoline-3-carboxylic acid ethyl ester

1-tert-Butyl-7-(3,4-dihydro-1H-isoquinolin-2-yl)-6-nitro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid ethyl ester