In the title pymiridine-2,4-dione derivative, C14H16N2O2S, the dihedral angle between the six-membered rings is 66.69 (10)°. The mol-ecule is twisted about the Cp-S (p = pyrimidine) bond, with a C-S-C-N torsion angle of -19.57 (16)°. In the crystal, adjacent mol-ecules form inversion dimers through pairs of strong N-H⋯O hydrogen bonds, generating an R 2 (2)(8) ring motif. The dimers are connected into chains extending along the c-axis direction through additional N-H⋯O hydrogen bonds.
The title compound, C19H23N3S, is a functionalized triazoline-3-thione derivative. The benzyl ring is almost normal to the planar 1,2,4-triazole ring (r.m.s. deviation = 0.007 Å) with a dihedral angle of 86.90 (7)°. In the crystal, molecules are linked by pairs of N-H⋯S hydrogen bonds, forming inversion dimers that enclose R 2 (2)(8) loops. The crystal packing is further stabilized by weak C-H⋯π inter-actions that link adjacent dimeric units into supra-molecular chains extending along the a-axis direction.
In the cation of the title salt, C11H17N2O(+)·C7H8ClN2O2 (-), the piperazine ring adopts a distorted chair conformation and contains a positively charged N atom with quaternary character. Its mean plane makes a dihedral angle of 42.36 (8)° with the phenyl ring of its 2-meth-oxy-phenyl substituent. The 2,4-dioxopyrimidin-1-ide anion is generated by deprotonation of the N atom at the 1-position of the pyrimidine-dione ring. Intra-molecular C-H⋯O hydrogen bonds generate S(6) ring motifs in both the cation and the anion. In the crystal, N-H⋯O, N-H⋯N and C-H⋯O hydrogen bonds are also observed, resulting in a two-dimensional network parallel to the ab plane. The crystal stability is further consolidated by weak C-H⋯π inter-actions.
The title 1,3,4-oxa-diazole-2-thione derivative, C18H20N4OS2, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. The 2-thienyl rings in both mol-ecules are rotationally disordered over two orientations by approximately 180° about the single C-C bond that connects it to the oxa-diazole thione ring; the ratios of site occupancies for the major and minor components were fixed in the structure refinement at 0.8:0.2 and 0.9:0.1 in mol-ecules A and B, respectively. The 1,3,4-oxa-diazole-2-thione ring forms dihedral angles of 7.71 (16), 10.0 (11) and 77.50 (12)° (mol-ecule A), and 6.5 (3), 6.0 (9) and 55.30 (12)° (mol-ecule B) with the major and minor parts of the disordered thio-phene ring and the mean plane of the adjacent piperazine ring, respectively, resulting in approximately V-shaped conformations for the mol-ecules. The piperazine ring in both mol-ecules adopts a chair conformation. The terminal benzene ring is inclined towards the mean plane of the piperazine ring with N-C-C-C torsion angles of -58.2 (3) and -66.2 (3)° in mol-ecules A and B, respectively. In the crystal, no inter-molecular hydrogen bonds are observed. The crystal packing features short S⋯S contacts [3.4792 (9) Å] and π-π inter-actions [3.661 (3), 3.664 (11) and 3.5727 (10) Å], producing a three-dimensional network.