2,6-Dimethyl-3-n-butyl-4-oxo-4H-pyrido(1,2-a)pyrimidine hydrochloride 3-Butyl-2,6-dimethyl-4H-pyrido(1,2-a)pyrimidin-4-one monohydrochloride 4H-Pyrido(1,2-a)pyrimidin-4-one, 3-butyl-2,6-dimethyl-, monohydrochloride 70381-28-1