1,8-Naphthyridine-3-carboxylic acid, 1,4-dihydro-1-(1,1-dimethylethyl)-6-fluoro-4-oxo-7-(1-piperazinyl)-

1-tert-Butyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydro-1,8-naphthyridine-3-carboxylic acid