3-{2-[2-(2-Fluorobenzylidene)hydrazinyl]-1,3-thiazol-4-yl}-2H-chromen-2-one

In the title compound, C19H12FN3O2S, the chromene ring system and the thiazole ring are approximately planar [maximum deviations of 0.023 (3) Å and 0.004 (2) Å, respectively]. The chromene ring system is inclined at angles of 4.78 (10) and 26.51 (10)° with respect to the thiazole and benzene rings, respectively, while the thiazole ring makes a dihedral angle of 23.07 (12)° with the benzene ring. The molecular structure is stabilized by an intramolecular C—H⋯O hydrogen bond, which generates an S(6) ring motif. The crystal packing is consolidated by intermolecular N—H⋯O hydrogen bonds, which link the molecules into chains parallel to [100], and by C—H⋯π and π–π [centroid–centroid distance = 3.4954 (15) Å] stacking interactions.

In the title compound, C 19 H 12 FN 3 O 2 S, the chromene ring system and the thiazole ring are approximately planar [maximum deviations of 0.023 (3) Å and 0.004 (2) Å , respectively]. The chromene ring system is inclined at angles of 4.78 (10) and 26.51 (10) with respect to the thiazole and benzene rings, respectively, while the thiazole ring makes a dihedral angle of 23.07 (12) with the benzene ring. The molecular structure is stabilized by an intramolecular C-HÁ Á ÁO hydrogen bond, which generates an S(6) ring motif. The crystal packing is consolidated by intermolecular N-HÁ Á ÁO hydrogen bonds, which link the molecules into chains parallel to [100], and by C-HÁ Á Á and -[centroid-centroid distance = 3.4954 (15) Å ] stacking interactions.

Comment
Coumarin derivatives constitute an important class of heterocyclic compounds having pronounced biological activities. For example, warfarin and cenocoumarol are used as anti-coagulants (Anderson et al., 2002;Tassies et al., 2002). These compounds also possess very good anti-bacterial (Mitscher, 2002;Lafitte et al., 2002), anti-fungal (Moffett, 1964) and cytotoxic activities (Weber et al., 1998). On the other hand, aminothiazole derivatives have been reported to exhibit significant antifungal (Hiremath et al., 1992), anti-bacterial (Habib & Khalil, 1984), and anti-tuberculosis activities (Karah et al., 1998;Gursoy & Karah, 2000). These compounds also have very important pharmaceutical value because of their anti-inflammatory (Lednicer et al., 1990), enzyme inhibition (Kim et al., 2002) and anti-tumour activities (Wattenberg et al., 1979). Our approach is the synthesis of biologically active compounds based on the combination of different substructures to enhance the biological activity of known compounds. The title compound is a new coumarin derivative having aminothiazole moiety.
We present here its crystal structure, Fig. 1.

Refinement
Atom H12N was located in a difference Fourier map and allowed to refined freely. The remaining hydrogen atoms were positioned geometrically and refined using a riding model with C-H = 0.93 Å and U iso (H) = 1.2 U eq (C). Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.The intramolecular C-H···O interaction is shown as a dashed line.

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
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 > σ(F 2 ) is used only for calculating Rfactors(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.