4-{[2-(2,4-Dinitro-phen-yl)hydrazinyl-idene]meth-yl}phenol ethanol hemisolvate.

In the title compound, C(13)H(10)N(4)O(5)·0.5C(2)H(5)OH, the two benzene rings form a dihedral angle of 4.29†(9)°. The ethanol solvent mol-ecule was treated as disordered between two orientations related by symmetry (center of inversion), with occupancies fixed at 0.5. The crystal packing, stabilized by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds and π-π inter-actions [indicated by the short distance of 3.7299†(7)†à between the centroids of benzene rings from neighbouring mol-ecules], exhibits short inter-molecular O⋯O contacts of 2.8226†(3)†à .