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

In the title thione–Schiff base compound, C(10)H(9)N(3)O(2)S(2), the dihedral angle between the benzene ring and the five-membered ring is 6.69 (8)°. An intra­molecular O—H⋯N hydrogen bond forms an S (2) (2)(6) ring. In the crystal, inversion dimers linked by pairs of N—H⋯S inter­actions occur, generating R (2) (2)(8) ring motifs. The crystal structure features a S⋯S contact [3.3776 (7) Å], which is significantly shorter than the sum of the van der Waals radii (3.7 Å). The crystal structure also features C—H⋯O and π–π inter­actions [centroid–centroid distances = 3.4636 (9)–3.808 (1) Å].