N-(2-{[5-Bromo-2-(piperidin-1-yl)pyrimidin-4-yl]sulfanyl}-4-methoxyphenyl)benzenesulfonamide

The title compound, C22H23BrN4O3S2, crystallizes with two molecules, A and B, in the asymmetric unit. In one of these, the methoxy group is disordered over two sets of sites in a 0.565 (9):0.435 (9) ratio. The benzene rings bridged by the sulfonamide group are tilted relative to each other by 37.4 (1) and 56.1 (1)° in molecules A and B, respectively, while the dihedral angles between the sulfur-bridged pyrimidine and benzene rings are 72.4 (1) and 70.2 (1)° for A and B, respectively. The piperidine ring adopts a chair conformation in both molecules. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds occur for both A and B; the dimers are linked into [010] chains by C—H⋯O hydrogen bonds. The crystal structure also features inversion-generated aromatic π–π stacking interactions between the pyrimidine rings for both molecules [centroid–centroid distances = 3.412 (2) (molecule A) and 3.396 (2) Å (molecule B)].

The title compound, C 22 H 23 BrN 4 O 3 S 2 , crystallizes with two molecules, A and B, in the asymmetric unit. In one of these, the methoxy group is disordered over two sets of sites in a 0.565 (9):0.435 (9) ratio. The benzene rings bridged by the sulfonamide group are tilted relative to each other by 37.4 (1) and 56.1 (1) in molecules A and B, respectively, while the dihedral angles between the sulfur-bridged pyrimidine and benzene rings are 72.4 (1) and 70.2 (1) for A and B, respectively. The piperidine ring adopts a chair conformation in both molecules. In the crystal, inversion dimers linked by pairs of N-HÁ Á ÁN hydrogen bonds occur for both A and B; the dimers are linked into [010] chains by C-HÁ Á ÁO hydrogen bonds. The crystal structure also features inversion-generated aromaticstacking interactions between the pyrimidine rings for both molecules [centroid-centroid distances = 3.412 (2) (molecule A) and 3.396 (2) Å (molecule B)]. H atoms treated by a mixture of independent and constrained refinement Á max = 0.34 e Å À3 Á min = À0.36 e Å À3 Table 1 Hydrogen-bond geometry (Å , ). structures (Rodrigues et al., 2011;Akkurt et al., 2011;Kant et al., 2012); Kumar et al. (2012). There are no significant differences in bond lengths and angles for molecule A & B. The molecules are twisted about the S-N bonds with (C1A -S1A-N8A-C9A) and (C1B-S1B-N8B-C9B) torsion angles of 60.5 (3) and 58.9 (4)°, respectively. The piperidine ring is in chair conformation in both the molecules. The benzene rings bridged by the sulfonamide group are tilted relative to each other by 37.4 (2) and 56.1 (1)° while the dihedral angle between the sulfur bridged pyrimidine and benzene rings is 72.4 (1) and 70.2 (1)° in molecules A and B, respectively. In one of the molecules (molecule A), methoxy group is disordered over two sets of sites in a 0.57 (1): 0.43 (1) ratio. In the crystal, molecule A is forming dimer with other molecule A by N8A-H8A ···N20A and molecule B is also forming dimer with molecule B by N8B-H8B ···N20B hydrogen bonds (Fig. 2). These dimers are further connected into chains by C10B-H10B···O2B and C11A-H11A···O1A along a axis (Fig. 3). In addition to these hydrogen bonds there is one intramolecular N8B-H8B···S2B hydrogen bond in molecule B (Table 1). The crystal structure also features π-π interactions between the pyrimidine rings in both the molecules, A & B [molecule A: centroid separation = 3.412 (2) Å, interplanar spacing = 3.401 Å and centroid shift = 0.27 Å; molecule B: centroid separation = 3.396 (2) Å, interplanar spacing = 3.322 Å and centroid shift = 0.70 Å].

Experimental
The reaction of N- [2-(5-bromo-2-piperidin-1-yl-pyrimidin-4-yl-sulfanyl) -4-methoxy-phenyl]-benzenesulfonamide (4.87 g, 0.01 mol) and piperidine (0.86 g, 0.01 mol) were carried out in the presence of triethylamine and the reaction mixture was allowed to stir at room temperature for 6-7 h in dry dichloromethane. The progress of the reaction was monitored by TLC. Upon completion, the solvent was removed under reduced pressure and residue was extracted with ethyl acetate.

Refinement
All H atoms were positioned geometrically and were treated as riding on their parent C/N atoms, with C-H distances of 0.93-0.97 Å and N-H distance of 0.86 with U iso (H) = 1.2U eq (C) or 1.5U eq (methyl C).

Figure 1
The molecular structure with displacnent ellipsoids drawn at the 40% probability level.

Figure 2
Dimer formation between the molecules.    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.