4-{[(1,3-Benzothia­zolium-2-yl)hydra­zono](phen­yl)meth­yl}-3-methyl-1-phenyl-1H-pyrazol-5-olate monohydrate

The title compound, C(24)H(19)N(5)OS·H(2)O, was synthesized by the reaction of 4-benzoyl-3-methyl-1-phenyl­pyrazol-5-one and 2-hydrazino-1,3-benzothia­zole. Proton transfer leads to the formation of a zwitterionic structure and the mol­ecule exists in the enolate form. The pyrazolone ring makes dihedral angles of 35.4 (3), 69.7 (3) and 40.1 (3)° with the 1-phenyl, indirectly bound phenyl and benzothia­zole ring systems, respectively. The mol­ecules are linked into one-dimensional chains by a combination of N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds.