(4-Methylphenyl)[1-(4-methylphenyl)-3-(5-nitro-2-furyl)-1H-pyrazol-4-yl]methanone

In the title pyrazole compound, C22H17N3O4, an intramolecular C—H⋯O contact generates a seven-membered ring, producing an S(7) ring motif. The furan and pyrazole rings are essentially planar [maximum deviations = 0.004 (1) and 0.004 (2) Å, respectively] and are almost coplanar, making a dihedral angle of 3.75 (10)°. One of the methylphenyl groups is inclined to the pyrazole ring, as indicated by the dihedral angle of 48.41 (9)°. In the crystal structure, molecules are linked into chains along [10] by C—H⋯O contacts. The crystal structure is further stabilized by π–π interactions [centroid–centroid distance = 3.4437 (10) Å].

In the title pyrazole compound, C 22 H 17 N 3 O 4 , an intramolecular C-HÁ Á ÁO contact generates a seven-membered ring, producing an S(7) ring motif. The furan and pyrazole rings are essentially planar [maximum deviations = 0.004 (1) and 0.004 (2) Å , respectively] and are almost coplanar, making a dihedral angle of 3.75 (10) . One of the methylphenyl groups is inclined to the pyrazole ring, as indicated by the dihedral angle of 48.41 (9) . In the crystal structure, molecules are linked into chains along [110] by C-HÁ Á ÁO contacts. The crystal structure is further stabilized byinteractions [centroid-centroid distance = 3.4437 (10) Å ].

Comment
Pyrazole derivatives are in general well-known nitrogen-containing heterocyclic compounds and various procedures have been developed for their syntheses (Rai & Kalluraya, 2006). The chemistry of pyrazole derivatives has been the subject of much interest due to their importance for various applications, and their widespread potential and proven biological and pharmacological activities (Rai et al., 2008). Steroids containing pyrazole moiety are of interest as psychopharmacological agents. Some alkyl-and aryl-substituted pyrazoles have a sharply pronounced sedative action on the central nervous system. Further, certain alkyl pyrazoles show significant bacteriostatic, bacteriocidal and fungicidal, analgesic and anti-pyretic activities (Sridhar & Perumal, 2003). In continuation of our studies on 1,3-dipolar cyclo-addition reactions of sydnones with dipolarophiles carrying a nitrofuran or nitrothiophene moiety (Kalluraya et al., 1994), we herein report the synthesis of this new pyrazole possessing 5-nitrofuran nucleus, (I).
Experimental 3-(p-methylphenyl)sydnone (0.01 mol) and 1-(p-methylphenyl)-3-(5-nitro-2-furyl)-2-propyn-1-one (0.01 mol) were dissolved in dry xylene (10 ml) and refluxed for 4 h. After completion of the reaction, the solvent was removed by distillation under reduced pressure. The crude product obtained was purified by recrystallization from ethanol and DMF mixture. The solid obtained was collected by filtration, washed with ethanol and dried. Single crystals were obtained by by slow evaporation of a DMF and ethanol (1:2) solution of (I).

Refinement
All the hydrogen atoms were placed in their calculated positions, with C-H = 0.93 -0.96 Å, and refined using a riding model, with U iso = 1.2 or 1.5 U eq (C). A rotating group model was used for the methyl groups.  Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme. An intramolecular C-H···O contact is shown as 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 > 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.