4-[2-(2-Methoxyphenyl)hydrazinylidene]-3-methyl-5-oxo-4,5-dihydro-1H-pyrazole-1-carbothioamide

In the title molecule, C12H13N5O2S, a bifurcated intramolecular N—H⋯O(O) hydrogen bond forms two S(6) ring motifs. The benzene ring forms a dihedral angle of 14.36 (11)° with the pyrazole ring. In the crystal, pairs of N—H⋯S hydrogen bonds form centrosymmetric dimers, generating R 2 2(8) ring motifs, which stack along the b axis.

In the title molecule, C 12 H 13 N 5 O 2 S, a bifurcated intramolecular N-HÁ Á ÁO(O) hydrogen bond forms two S(6) ring motifs. The benzene ring forms a dihedral angle of 14.36 (11) with the pyrazole ring. In the crystal, pairs of N-HÁ Á ÁS hydrogen bonds form centrosymmetric dimers, generating R 2 2 (8) ring motifs, which stack along the b axis.

Comment
Pyrazoles are a novel class of heterocyclic compounds possessing a wide variety of application in the agrochemical and pharmaceutical industries. Derivatives of pyrazoles are found to show good antibacterial (Rai et al., 2008), anti-inflammatory, analgesic (Isloor et al., 2009), and anticancer activities. Pyrazolines are well known and important nitrogen-containing five membered heterocyclic compounds. Several pyrazoline derivatives have been found to possess considerable biological activities which stimulated research activities in this field (Girisha et al., 2010). In view of these observations and in continuation of our search for biologically active pyrazole derivatives, we herein report the crystal structure of the title compound.
The crystal packing is shown in Fig. 2. Molecules are linked by pairs of intermolecular N5-H1N5···S1 i hydrogen bonds (Table 1) to form dimers, generating R 2 2 (8) ring motifs (Bernstein et al., 1995) and these sets of ring motifs are stacked along the b axis.

Experimental
To a solution of ethyl 2-[(2-methoxyphenyl)hydrazono]-3-oxobutanoate (0.01 mol) in glacial acetic acid (20 ml), a solution of thiosemicarbazide (0.02 mol) in glacial acetic acid (15 ml) was added and the mixture was refluxed for 4 h. It is cooled and allowed to stand overnight. The solid product that separated out was filtered and dried. It was then recrystallized from ethanol. Crystals suitable for X-ray analysis were obtained from 1:2 mixtures of DMF and ethanol by slow evaporation.

4-
Cell parameters from 5668 reflections a = 14.3207 (13)  as those based on F, and R-factors based on ALL data will be even larger.