The title compound, C(25)H(19)NO(4)S, (IV), was produced by a cyclocondensation reaction similar to that which had previously produced an unexpected product, thus giving a novel route for such reactions. The structure of (IV) contains two S(6) motifs formed by strong intramolecular O-H.O hydrogen bonds. Weak C-H.O hydrogen bonds form primary C(11), R(1)(2)(7) and R(2)(2)(8) motifs which combine to form a complex three-dimensional network.