8,13,26-Trioxa-23-thia-21-azapentacyclo[18.6.0.02,7.014,19.021,25]hexacosa-2(7),3,5,14,16,18-hexaene

In the title compound, C21H23NO3S, both the thiazole and oxazolidine rings adopt twist conformations. The mean plane of the thiazole ring makes a dihedral angle of 61.02 (7)° with the oxazolidine ring mean plane, and dihedral angles of 22.72 (6) and 75.07 (6)° with the benzene rings. The benzene rings are almost perpendicular to one another, making a dihedral angle of 89.14 (6)°. There are bifurcated intramolecular C—H⋯O hydrogen bonds in the molecular structure. In the crystal, molecules are linked via C—H⋯π interactions, forming chains propagating along [100].

In the title compound, C 21 H 23 NO 3 S, both the thiazole and oxazolidine rings adopt twist conformations. The mean plane of the thiazole ring makes a dihedral angle of 61.02 (7) with the oxazolidine ring mean plane, and dihedral angles of 22.72 (6) and 75.07 (6) with the benzene rings. The benzene rings are almost perpendicular to one another, making a dihedral angle of 89.14 (6) . There are bifurcated intramolecular C-HÁ Á ÁO hydrogen bonds in the molecular structure. In the crystal, molecules are linked via C-HÁ Á Á interactions, forming chains propagating along [100].

Experimental
Cg1 is the centroid of the C9-C14 ring.

Raghavachary Raghunathan and Devadasan Velmurugan Comment
Thiazole derivatives have a variety of physiological effects, such as antiinflammatory (Guo et al., 2006) and antimicrobial (Karegoudar et al., 2008). Against this background, we report herein on the crystal structure of the title thiazole derivative.
In the crystal, molecules are linked via C-H···π interactions forming chains along direction [100]; see Table 1.

Experimental
A mixture of 2,2′-(butane-1,4-diylbis(oxy))dibenzaldehyde (1 mMol) and thiazolidine-4-carboxylic acid (1 mMol) was refluxed in acetonitrile (30 ml) for about 6 hrs under N 2 atm. After the completion of reaction as indicated by TLC, acetonitrile was evaporated under reduced pressure. The crude product was purified by column chromatography using hexane: EtOAc (8:2) mixture as eluent. Block-like colourless crystals of the title compound, suitable for X-ray diffraction, were obtained by slow evaporation of a solution in ethyl acetate at room temperature.

Refinement
The H atoms were placed in calculated positions and treated as riding atoms: C-H = 0.93 -0.98 Å, with U iso (H) = 1.5U eq (C) for methyl H atoms and = 1.2U eq (C) for other H atoms.  The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level. 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 esds are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness 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 threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) 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.