N′-(Cyclohexylcarbonyl)isonicotinohydrazide

In the title compound, C13H17N3O2, the mean plane of the cyclohexane ring forms a dihedral angle of 33.12 (5)° with the pyridine ring. The two O atoms are twisted away from each other, as indicated by the C—N—N—C torsion angle of −74.97 (9)°. In the crystal structure, molecules are linked into a three-dimensional network by intermolecular N—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds. The structure is also stabilized by C—H⋯π interactions.

In the title compound, C 13 H 17 N 3 O 2 , the mean plane of the cyclohexane ring forms a dihedral angle of 33.12 (5) with the pyridine ring. The two O atoms are twisted away from each other, as indicated by the C-N-N-C torsion angle of À74.97 (9) . In the crystal structure, molecules are linked into a three-dimensional network by intermolecular N-HÁ Á ÁN, N-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds. The structure is also stabilized by C-HÁ Á Á interactions.

Comment
In the search of new compounds, isoniazid derivatives have been found to possess potential tuberculostatic activity (Janin, 2007;Maccari et al., 2005;Slayden & Barry, 2000). As a part of a current work of synthesis of such derivatives, in this paper we present the crystal structure of the title compound which was synthesized in our lab.

Experimental
The isoniazid (INH) derivative was prepared following the procedure by literature (Besra et al., 1993). Dry dichloromethane (30 ml) and 4-dimethylaminopyridine (4-DMAP) (1.2 eq) was added to cyclohexane carbonyl chloride followed by INH (1.1 eq). The reaction mixture was kept in an ice bath for 1 h and then left stirring under nitrogen overnight at room temperature.
Dichloromethane (20 ml) was added to the reaction mixture, which was then washed with water, and the organic layer dried over anhydrous sodium sulphate. The solvent was removed under reduced pressure to afford the crude product which was purified by column chromatography and recrystallized from methanol to afford colorless crystals.

Refinement
All hydrogen atoms were located from the difference Fourier map and refined freely. As there are not enough anomalous dispersion effects to determine the absolute configuration, 2499 Friedel pairs were merged before final refinement. Fig. 1. The molecular structure of the title compound with atom labels and 50% probability ellipsoids for non-H atoms.  Glazer, 1986) operating at 100.0 (1)K.

N'-(Cyclohexylcarbonyl)isonicotinohydrazide
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 calculat-supplementary materials sup-3 ing 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.