2,3,6-Trimethyl-4-oxo-4H-pyrido(1,2-a)pyrimidine hydrochloride 2,3,6-Trimethyl-4H-pyrido(1,2-a)pyrimidin-4-one monohydrochloride 4H-Pyrido(1,2-a)pyrimidin-4-one, 2,3,6-trimethyl-, monohydrochloride 70381-27-0