7-(4-ethoxycarbonyl-1-piperazinyl)-1-ethyl-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid

哌嗪

1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(p-tolylsulfonyl)-1,8-naphthyridine-3-carboxylic acid

N-乙基-beta-丙氨酸乙酯

3-氰基-2,6-二氯-5-氟吡啶