1,8-Naphthyridine-3-carboxylic acid, 1,4-dihydro-6-chloro-1-ethyl-4-oxo-7-(1-piperazinyl)-, monohydrochloride 6-Chloro-1-ethyl-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine-3-carboxylic acid HCl 74274-59-2