2-((E)-{2-[(1E)-(2,4-Dihydroxy­benzyl­idene)amino]phen­yl}iminiometh­yl)-5-hydroxy­phenolate methanol solvate

The asymmetric unit of the title compound, C(20)H(16)N(2)O(4)·CH(3)OH, contains two Schiff base zwitterions and two methanol solvent mol­ecules. The dihedral angles between the central benzene ring and the two outer benzene rings of the Schiff base are 2.57 (7) and 52.30 (7)° in one mol­ecule and 5.83 (7) and 49.82 (7)° in the other mol­ecule. Intra­molecular O—H⋯N and N—H⋯O hydrogen bonds generate S(6) ring motifs, whereas intra­molecular N—H⋯N hydrogen bonds generate S(5) ring motifs. In the crystal structure, O—H⋯O, hydrogen bonds and weak C—H⋯O inter­actions link the mol­ecules into one-dimensional chains along the b-axis direction and are further connected by O—H⋯O and weak C—H⋯O inter­actions into a three-dimensional network. C—H⋯π and π–π inter­actions [centroid–centroid distances = 3.6228 (9) and 3.6881 (9) Å] are also observed in the crystal structure.