Date Published: August 01, 2012
Publisher: International Union of Crystallography
Author(s): Hoong-Kun Fun, Tze Shyang Chia, Ahmed M. Alafeefy, Hatem A. Abdel-Aziz.
In the title molecular salt, C16H13N2OS+·HSO4−, the thiazolo[3,2-a]benzimidazolium ring system is roughly planar [maximum deviation = 0.046 (3) Å] and makes a dihedral angle of 58.22 (11)° with the benzene ring. The methoxy group is almost coplanar with its attached benzene ring [Cmethyl—O—C—C = −1.6 (5)°]. In the crystal, the cation is linked to the anion by a bifurcated N—H⋯(O,O) hydrogen bond, generating an R12(4) ring motif. The ion pairs are then connected by a C—H⋯O hydrogen bond into inversion dimers and these dimers are further linked by O—H⋯O hydrogen bonds into an infinite tape along . A π–π stacking interaction [centroid-to-centroid distance = 3.5738 (18) Å] and a short intermolecular contact [S⋯O = 2.830 (3) Å] are also observed.
For the biological activities of thiazolo[3,2-a]benzimidazoles, see: Chimirri et al. (1988 ▶); Al-Rashood & Abdel-Aziz (2010 ▶); Hamdy et al. (2007 ▶); Abdel-Aziz et al. (2007 ▶, 2008 ▶); Farag et al. (2011 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ▶).