N'-[1-(5-Bromo-2-hydroxy-phen-yl)ethyl-idene]-3,4,5-trihydroxy-benzohydrazide dimethyl sulfoxide solvate trihydrate.

The benzohydrazide mol-ecule in the title compound, C(15)H(13)BrN(2)O(5)·C(2)H(6)OS·3H(2)O, is almost planar with an r.m.s. deviation for the non-H atoms of 0.078 Å. The organic mol-ecules, water and dimethyl sulfoxide solvent mol-ecules are linked by N-H⋯O, O-H⋯O and O-H⋯S inter-molecular hydrogen bonds, forming zigzag chains along the a axis. Intra-molecular O-H⋯O and O-H⋯N hydrogen bonds also occur.