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

6-Amino-1-tert-butyl-7-(2,3-dihydro-indol-1-yl)-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid ethyl ester

1-(tert-butyl)-7-chloro-6-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid