4,4'-Ethyl-enedipyridinium bis-(3,4,5-trihy-droxy-benzoate) sesquihydrate.

The asymmetric unit of the title compound, C(12)H(14)N(2) (2+)·2C(7)H(5)O(5) (-)·1.5H(2)O, contains two 4,4'-ethyl-enedipyridinium cations, four gallate anions and three water mol-ecules. In the 4,4'-ethyl-enedipyridinium cations, the dihedral angles between the pyridinium rings are 4.3 (3) and 18.6 (3)°. Extensive classical N-H⋯O and O-H⋯O hydrogen bonding and weak C-H⋯O hydrogen bonding and C-H⋯π inter-actions are present in the crystal structure. π-π stacking is also observed, the centroid-centroid separations between the benzene and pyridine rings being 3.611 (3), 3.448 (3) and 3.536 (3) Å.