(E)-2-{[4-(Di­methyl­amino)­benzyl­idene]amino}-5-nitro­phenol

The title Schiff base compound, C(15)H(15)N(3)O(3), crystallizes with two mol­ecules (A and B) in the asymmetric unit. Each mol­ecule adopts an E conformation around the C= N imine bond. The two mol­ecules have minor differences in their conformations. In mol­ecule A, the dihedral angle between the nitro group and its benzene ring is 2.1 (2)° and that between the two benzene rings is 0.88 (7)°, while the corresponding angles for mol­ecule B are 5.7 (1) and 2.45 (6)°, respectively. In each mol­ecule, there is an intra­molecular O—H⋯N hydrogen bond. In the crystal, inversion-related mol­ecules are linked via O—H⋯O hydrogen bonds forming A–A and B–B dimers. These dimers are linked via C—H⋯O hydrogen bonds involving the nitro O atoms, forming A–A–A and B–B–B slabs that lie parallel to one another and to (010).