(E)-3,4,5-Trimeth­oxy-N′-[(6-meth­oxy-4-oxo-4H-chromen-3-yl)methyl­idene]benzohydrazide monohydrate

In the title chromone-tethered benzohydrazide derivative, C(21)H(20)N(2)O(7)·H(2)O, the atoms of the 4H-chromen-4-one segment are essentially coplanar (r.m.s. deviation = 0.0073 Å) with the largest deviation from the mean plane [0.012 (3) Å] being found for the benzene C atom. The dihedral angles between the chromone segment and the hydrazide plane and between the chromone segment and the benzene ring of the tri­meth­oxy­benzene unit are 24.67 (9) and 41.28 (8) Å, respectively. The mol­ecule is connected to the solvent water mol­ecule by O—H⋯O hydrogen bonds and weak C—H⋯O inter­actions. Additional N—H⋯O inter­actions are observed and together they link the mol­ecules into chains forming a two-dimensional network along (011).