8-ethyl-5,8-dihydro-5-oxo-2-(piperazinyl)pyrido[2,3-d]pyrimidine-6-carboxylic acid hydrochloride

8-Ethyl-5,8-dihydro-5-oxo-2-(1-piperazinyl)pyrido[2,3-d]pyrimidine-6-carboxylic acid/hydrochloric acid,(1:x)