The mol-ecule of the title compound, C(7)H(6)N(2)S(3), is almost planar, the dihedral angle between the benzene plane and the 1,3-dithiole-2-thione plane being 2.21 (6)°. In the crystal, mol-ecules are linked by inter-molecular N-H⋯S and N-H⋯N hydrogen bonds into a three-dimensional network. The crystal packing also exhibits weak inter-molecular S⋯S inter-actions [3.5681 (9) Å].

In the title compound, C(4)H(6)N(2)OS(2), the dihedral angle between the five-membered heterocyclic ring and the plane of the eth-oxy group is 4.9 (2)°. The 1,3,4-thiadiazole-2-thione unit is planar, with an r.m.s. deviation of 0.011 Å from the corresponding squares plane defined by the seven constituent atoms. In the crystal, pairs of N-H⋯S hydrogen bonds link the mol-ecules into inversion dim...

In the title compound, C(17)H(18)N(2)S, the imidazolidine ring adopts a twisted conformation. In the crystal, mol-ecules are linked by slipped π-π inter-actions between the benzene rings of neighbouring mol-ecules [centroid-to-centroid distance = 3.903 (2) Å].

The studied crystal of the title compound, C(7)H(12)N(2)S, is a racemic mixture of two isomers, viz. S,S and R,R. The two isomers share the same position on a mirror plane in the space group P2(1)/m; thus all atoms except one are disordered between two positions in a 1:1 ratio. Inter-molecular N-H⋯S hydrogen bonds link the mol-ecules into chains propagating in the [010] direction.