2-((1E)-1-{2-[(2Z)-3,4-Diphenyl-2,3-dihydro-1,3-thiazol-2-ylidene]hydrazin-1-ylidene}ethyl)pyridin-1-ium bromide monohydrate

In the title compound, C22H19N4S+·Br−·H2O, the dihedral angles between the phenyl groups and the mean plane of the thiazolylidene ring are 34.69 (13) and 64.27 (13)°, respectively, while that between the thiazolylidene and pyridinium rings is 14.73 (13)°. In the crystal, zigzag chains of alternating bromide ions and water molecules associate through O—H⋯Br interactions run in channels approximately parallel to the b axis. These chains help form parallel chains of cations through N—H⋯O, C—H⋯N and C—H⋯Br hydrogen bonds.

In the title compound, C 22 H 19 N 4 S + ÁBr À ÁH 2 O, the dihedral angles between the phenyl groups and the mean plane of the thiazolylidene ring are 34.69 (13) and 64.27 (13) , respectively, while that between the thiazolylidene and pyridinium rings is 14.73 (13) . In the crystal, zigzag chains of alternating bromide ions and water molecules associate through O-HÁ Á ÁBr interactions run in channels approximately parallel to the b axis. These chains help form parallel chains of cations through N-HÁ Á ÁO, C-HÁ Á ÁN and C-HÁ Á ÁBr hydrogen bonds.

Comment
Several methods for the synthesis of thiazole derivatives have been developed (Zambon et al., 2008;Franklin et al., 2008;Karegoudar et al., 2008) with the most widely used method being the Hantzsch's synthesis utilizing thioamides and αhalocarbonyl compounds as the starting materials (Ochiai et al., 2003). 1,3-Thiazole scaffold compounds are present in many pharmacologically active substances (Masquelin & Obrecht, 2001). They have found to possess strong antiinflammatory (Hirai et al., 1980), antimicrobial (Ali & El-Kazak, 2010), antitumor  and selective cardiodepressant activities (Budriesi et al., 2008). Other compounds containing the thiazole ring have been reported as being histamine H3 antagonists (Walczynski et al., 2005) and herbicidals (Andreani et al., 1996). In view of these findings and as part of our efforts (Mague et al., 2014;Mohamed et al., 2013a,b) to identify new candidates that may be of value in designing new and potent antimicrobial agents we report the synthesis and crystal structure of the title compound.
In the crystal, zigzag chains of alternating bromide ions and water molecules associated through O-H···Br interactions run in channels approximately parallel to the b axis. These chains help form parallel chains of cations through N-H···O, C-H···N and C-H···Br hydrogen bonds ( Fig. 2 and Table 1).

Experimental
The title compound has been prepared according to our reported method (Mohamed et al., 2013b). Orange crystals suitable for X-ray diffraction (m.p.: 507 K) have been obtained by crystallization of the crude product (I) from ethanol.

Special details
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement on F 2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The observed criterion of F 2 > σ(F 2 ) is used only for calculating -R-factor-obs etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq S1 0.61850 (