In the title compound, C15H15NO4S, the dihedral angle between the benzene rings is 78.62 (16)°. In the crystal, adjacent mol-ecules are linked along the c axis into C(4) chains through strong N-H⋯O hydrogen bonds. Mol-ecules are further connected through C-H⋯O hydrogen bonds into a hexa-meric unit generating an R (6) 6(66) motif. Another C-H⋯O inter-action connects the mol-ecules along the c axis, forming C(5) chains. A region of disordered electron density, most probably disordered methanol-water solvent mol-ecules, was treated with the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. The formula mass and unit-cell characteristics do not take into account this disordered solvent.