N'-(3,4-Dihydroxy-benzyl-idene)acetohydrazide monohydrate.

In the title compound, C(9)H(10)N(2)O(3)·H(2)O, the Schiff base mol-ecule is approximately planar, the dihedral angle between the benzene and acetohydrazide planes being 5.40†(7)°. An intra-molecular O-H⋯O hydrogen bond is observed. In the crystal, mol-ecules are linked into a two-dimensional network parallel to (100) by O-H⋯O, N-H⋯O, O-H⋯N and C-H⋯O hydrogen bonds, and by π-π inter-actions between symmetry-related benzene rings [centroid-centroid distance = 3.543†(2)†à ].