Abstract
In the title molecule, C(16)H(13)NO(4)S, the heterocyclic thiazine ring adopts a half-chair conformation with the S and N atoms displaced by 0.410 (3) and 0.299 (3) angstrom, respectively, on opposite sides of the mean plane formed by the remaining ring atoms. The crystal structure is stabilized by intermolecular hydrogen bonds of the types O-H center dot center dot center dot O and C-H center dot center dot center dot O; the former result in dimers lying about inversion centers and the latter form chains of molecules running along the c axis. In addition, intramolecular O-H center dot center dot center dot O links are present.