4-{2-[2-(4-Chloro-benzyl-idene)hydrazinyl-idene]-3,6-dihydro-2H-1,3,4-thia-diazin-5-yl}-3-(4-meth-oxy-phen-yl)sydnone.

The title compound, C(19)H(15)ClN(6)O(3)S, exists in trans and cis configurations with respect to the acyclic C=N bonds. The 3,6-dihydro-2H-1,3,4-thia-diazine ring adopts a half-boat conformation. The sydnone ring is approximately planar [maximum deviation = 0.013 (1) Å] and forms dihedral angles of 34.76 (4) and 48.67 (4)° with the benzene rings. An intra-molecular C-H⋯O hydrogen bond stabilizes the mol-ecular structure and forms an S(6) ring motif. In the crystal packing, inter-molecular N-H⋯N hydrogen bonds link centrosymmetrically related mol-ecules into dimers, generating R(2) (2)(8) ring motifs. The dimers are then linked into a three-dimensional network by inter-molecular C-H⋯O and C-H⋯Cl hydrogen bonds, and by C-H⋯π inter-actions. Further stabilization is provided by π-π inter-actions involving the sydnone rings, with centroid-centroid separations of 3.4198 (5) Å.