In the title compound, C(13)H(12)N(2)O(4)S, the dihedral angle between the two aromatic rings is 89.5 (1)°. In the crystal structure, mol-ecules are linked by O-H⋯O(hydr-oxy) and N-H⋯O(sulfon-yl) hydrogen bonds, forming a ribbon that propagates along the b axis; there is also an intra-molecular O-H⋯N hydrogen bond.
The mol-ecule of the title compound, C(13)H(11)N(3)O(5)S, shows a phenyl group and an almost planar intra-molecularly hydrogen-bonded N'-(2-hydr-oxy-5-phenyl-ebenzyl-idene)hydrazino group disposed about the S atom. Adjacent mol-ecules are linked by N-H⋯O(nitro) hydrogen bonds, producing a linear chain that runs along the b axis of the unit cell.
The Cu atom in the title compound, [Cu(C(13)H(9)BrClN(2)O(3)S)(2)], is chelated by two deprotonated Schiff base ligands in a square-planar coordination geometry; the Cu atom lies on a center of inversion. The -NH- group of one anion forms an intra-molecular hydrogen bond to the phenolate atom of the symmetry-related ion.