4-Amino-N-(6-chloro-5-methoxypyrimidin-4-yl)benzenesulfonamide

In the title compound, C11H11ClN4O3S, the S atom is bonded in a distorted tetrahedral geometry, by two O atoms, a C atom of the benzene ring and an amino N atom. The essentially planar pyrimidine ring [maximum deviation = 0.020 (1) Å] forms a dihedral angle of 87.57 (5)° with the benzene ring. In the crystal structure, pairs of molecules are linked by intermolecular N—H⋯O hydrogen bonds to generate centrosymmetric R 2 2(8) ring motifs. In addition, molecules are linked into a three-dimensional extended network by intermolecular N—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds.

In the title compound, C 11 H 11 ClN 4 O 3 S, the S atom is bonded in a distorted tetrahedral geometry, by two O atoms, a C atom of the benzene ring and an amino N atom. The essentially planar pyrimidine ring [maximum deviation = 0.020 (1) Å ] forms a dihedral angle of 87.57 (5) with the benzene ring. In the crystal structure, pairs of molecules are linked by intermolecular N-HÁ Á ÁO hydrogen bonds to generate centrosymmetric R 2 2 (8) ring motifs. In addition, molecules are linked into a three-dimensional extended network by intermolecular N-HÁ Á ÁN, N-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds.

Comment
The importance of pyrimidines and analogous compounds in pharmaceutical and biological fields is well known (Townsend et al., 2002). Some substituted pyrimidines and their derivaties have been reported to possess anti-microbial and anti-fungal activities (El-Hashash et al., 1993). Pyrimidines have incidental anti-viral activity against herpes and vaccinia infections (Calabresi et al., 1975). A review on pyrimidines as anti-inflammatory agent is described by Amir et al. (2007). Sulfonamides are an important class of anti-bacterial drugs used in medicine and veterinary practice. Sulfa drugs are widely used in the treatment of infections, especially for patients intolerant to antibiotics. The vast commercial success of these medicinal agents has made the chemistry of sulfonamides to become a major area of research and an important branch of commercial importance in pharmaceutical sciences (Nagaraja et al., 2003). In view of the importance of the title compound possessing potential anti-bacterial properties, its crystal structure is reported herein.

Experimental
The title compound was obtained as a gift sample from R. L. Fine Chem, Bangalore, India. The compound was used without further purification. Single crystals of good quality were obtained from slow evaporation of an acetonitrile solution. M.p.

Refinement
All the H atoms were located in a difference Fourier map and allowed to refine freely [range of C-H = 0.90 (2) -0.991 supplementary materials sup-2 Figures   Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq