4-Benzylsulfanyl-1H-pyrazolo[3,4-d]pyrimidine

The pyrazolo[3,4-d]pyrimidine ring system of the title compound, C12H10N4S, is essentially planar [maximum deviation = 0.025 (1) Å for the C atom bearing the S atom] and almost perpendicular to the phenyl ring [dihedral angle = 71.42 (6)°]. In the crystal, molecules are linked via pairs of N—H⋯N hydrogen bonds, forming inversion dimers.

The pyrazolo [3,4-d]pyrimidine ring system of the title compound, C 12 H 10 N 4 S, is essentially planar [maximum deviation = 0.025 (1) Å for the C atom bearing the S atom] and almost perpendicular to the phenyl ring [dihedral angle = 71.42 (6) ]. In the crystal, molecules are linked via pairs of N-HÁ Á ÁN hydrogen bonds, forming inversion dimers.

Comment
Pyrazolo[3,4-d]pyrimidine derivatives are an important class of heterocyclic pharmaceuticals because of their significant and broad spectrum of biological properties, antiviral (Rashad et al., 2008); anti-mycobacterial (Ballell et al., 2007) and anticancer (Rashad et al., 2011). The present work is a continuation of the investigation of the sulfonamide derivatives published recently by our team (Moussaif et al., 2010;Ouzidan et al., 2011;Alsubari et al., 2011).
The crystal structure of title compound is build up from two fused six-membered rings (N1 to N4 C1 to C5) linked to a benzylsulfanyl group (S1 C6 to C12) as shown in Fig. 1. The fused rings system is almost planar with the largest deviation from the mean plane being -0.025 (1) A° at C5 atom. The dihedral angle between the benzyl cycle (C7 to C12) and the mean plane through the pyrazolo[3,4-d]pyrimidine system is of 71.42 (6)°. In the crystal, each molecule is linked to its symmetry equivalent created by a crystallographic inversion center by pairs of N3-H3N···N2 hydrogen bonds, forming inversion dimers as shown in Fig. 2 and Table 1.

Refinement
All H atoms could be located in a difference Fourier map. However, they were placed in calculated positions with C-H = 0.93-0.96 Å, N-H = 0.88 Å, and refined as riding on their parent atoms with U iso (H) = 1.2 U eq (C, N). In the last cycles of refinement, two outliers (0 0 2, 1 0 0) were omitted.

4-Benzylsulfanyl-1H-pyrazolo[3,4-d]pyrimidine
Crystal data Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 > σ(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.