2-Amino-5-methyl-3-(2-oxo-2-phenyl­eth­yl)-7-phenyl-4,5,6,7-tetra­hydro-3H-[1,2,4]triazolo[1,5-a]pyrimidin-8-ium bromide ethanol monosolvate

In the title compound, C₂₀H₂₂N₅O⁺·Br⁻·C₂H₆O, the tetra­hydro­pyrimidine ring of the bicyclic cation adopts a half-chair conformation with an equatorial orientation of the phenyl and methyl substituents. The amino group is nearly coplanar with the 1,2,4-triazole ring [interplanar angle = 4.08 (8)°] and has a slightly pyramidal configuration. The mean planes of the triazole ring and the benzene ring of the phenacyl group form a dihedral angle of 88.58 (7)°. In the crystal, N—H...Br, N—H...O and O—H...Br hydrogen bonds link the cations, anions and ethanol mol­ecules into layers parallel to the bc plane.