Crystal structure of (E)-N′-(5-bromo-2-hy­droxy­benzyl­idene)nicotinohydrazide monohydrate

In the title compound, C(13)H(10)BrN(3)O(2)·H(2)O, the conformation about the azomethine double bond is E. The mol­ecule exists in the amido form with a C=O bond length of 1.229 (2) Å. There is an intra­molecular O—H⋯N hydrogen bond forming an S(6) ring motif. The whole mol­ecule is almost planar, with an r.m.s. deviation of 0.021 Å for all non-H atoms, and the dihedral angle between the planes of the pyridine and benzene rings is 0.74 (12)°. In the crystal, the water mol­ecule of crystallization links the organic mol­ecules via Ow—H⋯O, Ow—H⋯N and N—H⋯Ow hydrogen bonds and short C—H⋯Ow contacts, forming sheets lying parallel to (100). Within the sheets there is a weak π–π inter­action involving the pyridine and benzene rings [centroid-to-centroid distance = 3.8473 (15) Å]. The sheets are linked via C—H⋯Br inter­actions, forming a three-dimensional network.