21271-25-0 3-Phenyl-2-(2-piperidinoethoxy)-4H-pyrazino(1,2-a)pyrimidin-4-one monohydrobromide 4H-Pyrazino(1,2-a)pyrimidin-4-one, 3-phenyl-2-(2-piperidinoethoxy)-, monohydrobromide