2-(3,4-Dimethyl-5,5-dioxo-2H,4H-pyrazolo-[4,3-c][1,2]benzothia-zin-2-yl)-N-(3-meth-oxy-benz-yl)acetamide.

The asymmetric unit of the title compound, C(21)H(22)N(4)O(4)S, contains two mol-ecules (A and B), in which the thia-zine rings adopt an S-envelope conformation with the S atoms displaced by 0.621 (2) and 0.697 (2) Å from the mean planes formed by the remaining ring atoms. The dihedral angles between the N-methyl-acetamide groups and the meth-oxy-benzene rings are 8.67 (10) and 54.49 (6)° in the two mol-ecules and the equivalent torsion angles in the N-methyl-acetamide chains connecting the ring systems also differ. In the crystal, N-H⋯O hydrogen bonds connect the components into C(4) [100] chains of alternating A and B mol-ecules. The packing is consolidated by weak C-H⋯O inter-actions, which generate a three-dimensional network.