(Z)-N′-(3-Ethyl-4-oxothiazolidin-2-ylidene)-2-[6-(4-methoxyphenyl)imidazo[2,1-b]thiazol-3-yl]acetohydrazide

Abstract

The title compound, C 19 H 19 N 5 O 3 S 2 , crystallizes in the triclinic space group P1, with two independent molecules (A and B) in the asymmetric unit (Z 0 = 2). The imidazo [2,1-b] [1,3]thiazole ring systems in molecules A and B are essentially planar (r.m.s deviations = 0.004 and 0.005 Å , respectively), with dihedral angles of 1.1 (3) and 0.8 (3) , respectively, between the thiazole and imidazole rings. The mean planes of these ring systems make dihedral angles of 16.0 (2) and 61.9 (2) for molecule A, and 11.8 (2) and 74.3 (2) for molecule B, with the 1,3-thiazolidine and methoxy-substituted benzene rings, respectively. In the crystal, molecules are linked via N-HÁ Á ÁO hydrogen bonds, forming -A-B-A-Bchains along [100]. The chains are linked by C-HÁ Á ÁO hydrogen bonds, forming layers parallel to the ab plane. Structure descriptionContinuing our work on the synthesis and crystal structure analyses of imidazo[2,1-b]thiazole derivatives (Akkurt et al., 2007(Akkurt et al., , 2008(Akkurt et al., , 2011(Akkurt et al., , 2012, we report herein on the synthesis and crystal structure of the title compound.The asymmetric unit ( (2) for molecule A, and 11.8 (2) and 74.3 (2) for molecule B, with the 1,3- et al., 2007, 2008, 2011, 2012). In the crystal, molecules are linked via N-HÁ Á ÁO hydrogen bonds, forming -A-B-A-B-chains along [100]; see Table 1 and Fig. 2. The chains are linked by C-HÁ Á ÁO hydrogen bonds, forming layers parallel to the ab plane; see Table 1 and Fig. 3. Table 1 Hydrogen-bond geometry (Å , ). Symmetry codes: (i) x þ 1; y; z; (ii) Àx; Ày þ 1; Àz þ 2; (iii) x; y À 1; z. Figure 2A partial view along the b axis of the crystal packing of the title compound. The chains propagating along [100] are generated by N-HÁ Á ÁO hydrogen bonds (dashed lines; see Table 1). Figure 3A view along the c axis of the crystal packing of the title compound. The N-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds are shown as dashed lines (see Table 1). Figure 1View of the molecular structure of the two independent molecules (A and B) of the title compound, with the atom labelling. Displacement ellipsoids are drawn at the 30% probability level. RefinementCrystal data, data collection and structure refinement details are summarized in Table 2. A total of 15 reflections showing poor agreement between |F o | 2 and |F c | 2 were omitted in the final cycles of refinement.