(E)-5-[(3-Ethoxy-2-hydroxybenzylidene)amino]-1,3,4-thiadiazole-2(3H)-thione

In the title compound, C11H11N3O2S2, the dihedral angle between the benzene ring and the five-membered ring is 6.85 (9)degrees. An intramolecular O-H center dot center dot center dot N hydrogen bond makes an S(6) ring motif. In the crystal, molecules are linked through bifurcated N-H center dot center dot center dot(O,O) hydrogen bonds with R-1(2)(5) ring motifs, forming chains along the b axis. A short C center dot center dot center dot S contact [3.3189 (19) angstrom], which is shorter than the sum of the van der Waals radii of these atoms (3.50 degrees), occurs in the structure. The crystal structure is further stabilized by C-H center dot center dot center dot N hydrogen bonding and pi-pi interactions [centroid-centroid distance = 3.7649 (12) angstrom].