4-Amino-3-[(4-methoxyphenyl)aminomethyl]-1H-1,2,4-triazole-5(4H)-thione

The molecule of the title compound, C10H13N5OS, is approximately planar, the dihedral angle between the triazole and benzene rings being 4.53 (10)°. The amino group adopts a pyramidal configuration. In the crystal structure, molecules are linked into two-dimensional networks parallel to (001) by intermolecular N—H⋯S and N—H⋯N hydrogen bonds. In addition, an S⋯S short contact of 3.3435 (7) Å is observed.

The molecule of the title compound, C 10 H 13 N 5 OS, is approximately planar, the dihedral angle between the triazole and benzene rings being 4.53 (10) . The amino group adopts a pyramidal configuration. In the crystal structure, molecules are linked into two-dimensional networks parallel to (001) by intermolecular N-HÁ Á ÁS and N-HÁ Á ÁN hydrogen bonds. In addition, an SÁ Á ÁS short contact of 3.3435 (7) Å is observed.
Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009  Comment 1,2,4-triazole and its derivatives were reported to exhibit various pharmacological activities such as antimicrobial, analgesic, anti-inflammatory, anticancer and antioxidant properties (Amir et al., 2008;Krzysztof et al., 2008;Kuş et al., 2008;Padmavathi et al., 2008). A few derivatives of triazoles have exhibited antimicrobial activity (Isloor et al., 2009). Some of the present day drugs such as ribavirin (antiviral agent), rizatriptan (antimigraine agent), alprazolam (anxiolytic agent), fluconazole and itraconazole (antifungal agents) are the best examples for potent molecules possessing the triazole nucleus. The amino and mercapto groups of 1,2,4-triazoles serve as readily accessible nucleophilic centers for the preparation of N-bridged heterocycles. Keeping in view of the biological importance, we have synthesized the title compound and its crystal structure is reported here.
Experimental 2-[(4-Methoxyphenyl)amino]acetohydrazide (19.5 g, 0.1 mol) was added slowly to a solution of potassium hydroxide (8.4 g, 0.15 mol) in ethanol (150 ml). The resulting mixture was stirred well till a clear solution was obtained. Carbon disulfide (11.4 g, 0.15 mol) was added dropwise and the contents were stirred vigorously. Further stirring was continued for 24 h.
The resulting mixture (Holla & Udupa, 1992) was diluted with 100 ml of ether and the precipitate formed was collected by filtration, washed with dry ether and dried at 338 K under vacuum. It was used for the next step without any purification.
A mixture of above synthesized potassium dithiocarbazinate (30.9 g, 0.1 mol), hydrazine hydrate (99%, 0.2 mol) and water (2 ml) was gently heated to boil for 30 min. Heating was continued until the evaluation of hydrogen sulfide ceases.
The reaction mixture was cooled to room temperature, diluted with water (100 ml) and acidified with 2 N HCl. The solid mass that separated was collected by filtration, washed with water and dried. Recrystallization was done from ethanol (yield: 15.1 g, 67.7%; m.p. 484-486 K).

Refinement
N-bound H atoms were located in a difference Fourier map and refined freely. The remaining H atoms were positioned geometrically [C-H = 0.93-0.97 Å] and refined using a riding model, with U iso (H) = 1.2U eq (C) and 1.5U eq (methyl C). A rotating group model was used for the methyl groups.  Fig. 1. The molecular structure of the title compound, with atom labels and 50% probability ellipsoids for non-H atoms.  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.