3-(4-Nitrophenyl)-1H-1,2,4-triazole-5(4H)-thione

In the title compound, C8H6N4O2S, the 1,2,4-triazole ring and the nitro group form dihedral angles of 6.26 (13) and 9.5 (3)°, respectively, with the phenyl ring. In the crystal, the molecules are linked via pairs of N—H⋯S hydrogen bonds, generating [010] chains which contain R 2 2 (8) ring motifs. The crystal structure is further stabilized by π–π stacking [centroid–centroid distance = 3.5491 (14) Å] interactions.


Comment
The 1,2,4-triazole nucleus has been incorporated into a wide variety of therapeutically interesting compounds. Several compounds containing 1,2,4-triazole rings are well known as drugs. For example, fluconazole is used as an antimicrobial drug (Shujuan et al., 2004), whereas vorozole, letrozole and anastrozole are non-steroidal drugs used for the treatment of cancer (Clemons et al., 2004) and loreclezole is used as an anticonvulsant (Johnston, 2002). Similarly substituted derivatives of triazole possess comprehensive bioactivities such as antimicrobial, anti-inflammatory, analgesic, antihypertensive, anticonvulsant and antiviral activities (Wei et al., 2007). Due to the progress that occurs in dealing with the chemistry of 1,2,4triazoles as well as their biological activity, we synthesized and reported the crystal structure of the title compound.
After the mixture was cooled to room temperature, it was then neutralized by the gradual addition of glacial acetic acid. The solid product obtained was collected by filtration, washed with ethanol and dried. It was then recrystallized using ethanol.
Yellow blocks of (I) were obtained from ethanol solution by slow evaporation.

Refinement
Atoms H1N1 and H1N2 were located from the difference Fourier map and refined freely [N-H = 0.80 (3)

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems 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.