Methyl 2-methyl-4-(oxiran-2-ylmeth­oxy)-2H-1,2-benzothia­zine-3-carboxyl­ate 1,1-dioxide

In the title compound, C(14)H(15)NO(6)S, the thia­zine ring adopts a distorted half-chair conformation. The structure displays several cooperative weak inter­molecular C—H⋯O hydrogen-bonding inter­actions, giving rise to a two-dimensional sheet packing motif. The CH(2) group in the meth­oxy linker to the oxirane ring, and the CH group in that ring, exhibit twofold positional disorder. The three-membered oxirane ring is twisted approximately perpendicular with respect to thia­zine ring (dihedral angle = 60/86° for the major/minor disorder components). 1,2-Benzothia­zines of this kind have a wide range of biological activities and are mainly used as medicines in the treatment of inflammation and rheumatoid arthritis.