2-{(E)-1-[2-(4-Nitrophenyl) Hydrazin-1-Ylidene] Ethyl}Benzene-1,3-Diol

The title compound, C(14)H(13)N(3)O(4), is close to planar, the dihedral angle between the terminal benzene rings being 5.80 (16)°; the nitro group is coplanar with the benzene ring to which it is bonded [O-N-C-C torsion angle = -177.3 (3)°]. The hy-droxy group forms an intra-molecular hydrogen bond with the imine N atom, and the conformation about the imine bond is E. In the crystal, layers in the (101) plane with an undulating topology are formed by O-H⋯O and N-H⋯O hydrogen bonds along with C-H⋯O inter-actions. Centrosymmetrically related layers are connected via π-π inter-actions [ring centroid-centroid distance = 3.5739 (19) Å] into double layers.