Methidathion: S-(5-meth-oxy-2-oxo-2,3-dihydro-1,3,4-thia-diazol-3-yl)methyl O,O-dimethyl phospho-rodithio-ate.

The title compound, C(6)H(11)N(2)O(4)PS(3), crystallizes with two independent mol-ecules in the asymmetric unit. The dihedral angles between the thia-diazole ring planes and the PS(2) planes of the phospho-rodithio-ate group are 86.51 (5) and 56.33 (5)° in the two mol-ecules. In the crystal, weak inter-molecular S⋯S [3.570 (8) Å] inter-actions and C-H⋯O and C-H⋯N hydrogen bonds contribute to the stabilization of the packing.