(E)-4-{[(3-Propyl-5-sulfanyl-idene-4,5-dihydro-1H-1,2,4-triazol-4-yl)imino]-meth-yl}-3-(p-tol-yl)-1,2,3-oxadiazol-3-ium-5-olate.

The title compound, C(15)H(16)N(6)O(2)S, exists in a trans configuration with respect to the acyclic N=C bond. The 1,2,3-oxadiazol-3-ium ring makes dihedral angles of 10.59 (8) and 73.94 (8)°, respectively, with the 1,2,4-triazole and benzene rings. The mol-ecular structure is stabilized by an intra-molecular C-H⋯S hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked into inversion dimers by pairs of inter-molecular N-H⋯S hydrogen bonds, generating eight-membered R(2) (2)(8) ring motifs. The dimers are further connected by C-H⋯O hydrogen bonds, forming a sheet parallel to the bc plane. The ethyl group is disordered over two sets of sites with occupancies of 0.744 (7) and 0.256 (7).