N′-Benzoyl-5-methyl-1,3-diphenyl-1H-pyrazole-4-carbohydrazide

In the title compound, C24H20N4O2, the pyrazole ring makes dihedral angles of 47.57 (10)° and 30.56 (11)° with its N-bound and C-bound phenyl groups, respectively. The C—N—N—C group that links the two carbonyls has a torsion angle of 81.5 (2)°. The torsion angles between the carbonyl groups and their adjacent pyrazole and phenyl rings are 125.89 (19) and 164.22 (17)°, respectively. In the crystal, pairs of molecules are linked by N—H⋯O hydrogen bonds into R 2 2(10) ring motifs, which in turn link to form chains that propagate parallel to the c-axis direction.

In the title compound, C 24 H 20 N 4 O 2 , the pyrazole ring makes dihedral angles of 47.57 (10) and 30.56 (11) with its N-bound and C-bound phenyl groups, respectively. The C-N-N-C group that links the two carbonyls has a torsion angle of 81.5 (2) . The torsion angles between the carbonyl groups and their adjacent pyrazole and phenyl rings are 125.89 (19) and 164.22 (17) , respectively. In the crystal, pairs of molecules are linked by N-HÁ Á ÁO hydrogen bonds into R 2 2 (10) ring motifs, which in turn link to form chains that propagate parallel to the c-axis direction.

Comment
Compounds that contain the pyrazole moiety are known to exhibit a wide range of biological properties such as antimalarial (Cunico et al., 2006), anti-tumor (Farag et al., 2008) and anti-inflammatory activities (Sharma et al., 2010). In addition, pyrazoles have a wide variety of application in the agrochemical and pharmaceutical industries (Patel et al., 2004). Recently we have reported the synthesis of substituted pyrazoles (Shridevi Doddaramappa et al., 2013). As an extension of our work on the structural characterization of pyrazoles, the title compound was prepared and characterized by single-crystal X-ray diffraction.
In the molecular structure of the title compound ( Fig. 1), the bond lengths and angles are generally within normal ranges and are comparable to those in a related structure (Chandra et al., 2012). The pyrazole moiety makes a torsion angle of 47.57 (10)° and 30.56 (11)° with the N-bound phenyl (C8-C13) and C-bound phenyl (C14-C19) groups, respectively. Also, the pyrazole ring makes a torsion angle of 51.36 (10)° with the amide group (C4/C19/O20/N21). The C-N-N-C group that links the two carbonyls has a torsion angle of 81.5 (2)°. Torsion angles between the carbonyl groups and their adjacent pyrazole and phenyl rings are 125.89 (19)° and 164.22 (17)°, respectively. In the crystal, pairs of molecules are linked by N-H···O hydrogen bonds into R 2 2 (10) ring motifs, which in turn link to form chains that propagate parallel to the c axis (Fig. 2).

Experimental
To pyrazole 4-carboxylic acid in CH 2 Cl 2 (5 ml), ethyl-(N′,N′-dimethylamino)propylcarbodiimide hydrochloride (EDC·HCl, 1.2 mmol) and 1-hydroxybenzotriazole (HOBt, 1.2 mmol) and then benzohydrazide (0.136 g, 1.0 mmol) was added and stirred at 25° C for 8-12 h. After completion of the reaction, the reaction mixture was extracted with ethyl acetate and the combined organic phase was washed with brine and dried over anhydrous sodium sulfate. Ethyl acetate was distilled off and the residue thus obtained was purified by column chromatography to give a white solid. The typical size of the block-shaped crystals was 0.30 × 0.25 × 0.20 mm.

Refinement
Carbon-bound H atoms were positioned geometrically and allowed to ride on their parent atoms with C-H distances in the range of 0.93 to 0.96 Å, respectively. U iso (H) values were set to 1.2-1.5U eq of the attached atom. The coordinates of H-atoms attached to nitrogen were allowed to refine.

Figure 1
Perspective diagram of the molecule with 50% probability displacement ellipsoids.  Packing diagram of the structure viewed down the 'b′ axis.

N′-Benzoyl-5-methyl-1,3-diphenyl-1H-pyrazole-4-carbohydrazide
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.