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

8-Ethyl-5-oxo-2-(piperazin-1-yl)-5,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylic acid--hydrogen chloride (1/1)