5-[(Z)-2,3-Dimeth-oxy-benzyl-idene]-1,2,4-triazolo[3,2-b][1,3]thia-zol-6(5H)-one.

The title compound, C(13)H(11)N(3)O(3)S, was synthesized from 1H-1,2,4-triazole-5-thiol in a one pot reaction. The fused thia-zolo[3,2-b][1,2,4]triazole system is essentially coplanar with the benzene ring: they enclose an inter-planar angle of 1.37†(13)°. The olefinic double bond is in a Z conformation. In the crystal, C-H⋯N hydrogen bonds link the mol-ecules into double layers parallel to the ab plane.