Ethidium benzoate methanol monosolvate.

In the title salt solvate (systematic name: 8-amino-5-ethyl-6-phenyl-phenanthridin-5-ium benzoate methanol monosolvate), C21H20N3 +·C6H5CO2 -·CH3OH, two ethidium cations, C21H20N3 +, dimerize about a twofold axis through π-π inter-actions [inter-centroid separation = 3.6137 (4) Å]. The benzoate anions are connected through hydrogen bonding with the -NH2 groups of the ethidium cations and the -OH group of the MeOH mol-ecule. The MeOH mol-ecule also accepts a hydrogen bond from the -NH2 group of the ethidium cation. The result is a one-dimensional hydrogen-bonded chain along the b-axis direction.