Date Published: April 01, 2011
Publisher: International Union of Crystallography
Author(s): Hoong-Kun Fun, Ching Kheng Quah, Nithinchandra, Balakrishna Kalluraya.
The title compound, C18H14N6O2S, exists in trans and cis configurations with respect to the two acyclic C=N bonds [bond lengths = 1.2835 (9) and 1.3049 (9) Å]. The 3,6-dihydro-2H-1,3,4-thiadiazine ring adopts a half-boat conformation. The oxadiazol-3-ium ring makes dihedral angles of 53.70 (4) and 60.26 (4)° with the two phenyl rings. In the crystal, molecules are linked via pairs of intermolecular N—H⋯N hydrogen bonds, generating R22(8) ring motifs, and are further linked via intermolecular C—H⋯O and C—H⋯S hydrogen bonds into a three-dimensional network. The short intermolecular distance between the oxadiazol-3-ium rings [3.4154 (4) Å] indicates the existence of a π–π interaction.
For general background to and the biological activity of sydnone derivatives, see: Newton & Ramsden (1982 ▶); Wagner & Hill (1974 ▶); Kalluraya & Rahiman (1997 ▶). For the preparation, see: Kalluraya et al. (2003 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶). For bond-length data, see: Allen et al. (1987 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For ring conformations, see: Cremer & Pople (1975 ▶).