(E)-N'-(3,4-Di-meth-oxy-benzyl-idene)nicotinohydrazide monohydrate.

In the title hydrated compound, C15H15N3O3·H2O, the nicotinohydrazide mol-ecule adopts a trans conformation with respect to the C=N double bond. The dihedral angle between the benzene and pyridine rings is 5.10 (14)°. In the crystal, the solvent water mol-ecule acts as an acceptor, forming an N-H⋯O hydrogen bond supported by two C-H⋯O contacts. It also acts as a donor, forming bifurcated O-H⋯(O,O) and O-H⋯N hydrogen bonds that combine with the former contacts to form zigzag chains of mol-ecules along the c-axis direction. An additional O-H⋯O donor contact completes a set of six hydrogen bonds to and from the water mol-ecule and connects it to a third nicotinohydrazide mol-ecule. This latter contact combines with weaker C-H⋯O hydrogen bonds supported by a C-H⋯π contact to stack mol-ecules along b in a three-dimensional network.