title: 4-{(Z)-2-[(E)-Benzyl-idenehydrazinyl-idene]-3,6-dihydro-2H-1,3,4-thia-diazin-5-yl}-3-phenyl-1,2,3-oxadiazol-3-ium-5-olate.
abstract: The title compound, C(18)H(14)N(6)O(2)S, 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-thia-diazine 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, mol-ecules are linked via pairs of inter-molecular N-H⋯N hydrogen bonds, generating R(2) (2)(8) ring motifs, and are further linked via inter-molecular C-H⋯O and C-H⋯S hydrogen bonds into a three-dimensional network. The short inter-molecular distance between the oxadiazol-3-ium rings [3.4154 (4) Å] indicates the existence of a π-π inter-action.
authors.forename: Hoong-Kun
authors.initials: HK
authors.lastname: Fun
authors.forename: Ching Kheng
authors.initials: CK
authors.lastname: Quah
authors.lastname: Nithinchandra
authors.forename: Balakrishna
authors.initials: B
authors.lastname: Kalluraya