2-(3-Oxo-3,4-dihydro-2H-1,4-benzothia-zin-4-yl)acetamide.

In the title compound, C(10)H(10)N(2)O(2)S, the thia-zine ring approximates to an envelope form with the S atom in the flap position. The amide group attached to the acetate group is almost perpendicular to the mean plane of the thia-zine ring [dihedral angle = 88.83 (8)°]. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds occur. Further N-H⋯O and C-H⋯O hydrogen bonds link the dimers into a three-dimensional network.