Mol-ecular and crystal structure of methyl 4-methyl-2,2-dioxo-1 H -2λ 6 ,1-benzo-thia-zine-3-carboxyl-ate.

The title compound, C11 H11 NO4 S, possesses weak analgesic properties and is a source compound for the synthesis of highly active analgesic and anti-inflammatory compounds. The benzo-thia-zine ring adopts a conformation intermediate between twist-boat and sofa. The ester substituent is turned towards the endocyclic double bond because of steric repulsion. In the crystal, the mol-ecules form columns along the [001] direction, bound by N-H⋯O hydrogen bonds and stacking inter-actions.