2-Benzylsulfanyl-4-pentyl-6-(phenylsulfanyl)pyrimidine-5-carbonitrile

In the title pyrimidine derivative, C23H23N3S2, the phenylsulfanyl and benzylsulfanyl benzene rings are orientated away from the carbonitrile group and are twisted out of the plane of the central ring with dihedral angles of 77.66 (6) and 64.73 (5)°, respectively. The n-pentyl group has an extended trans conformation. In the crystal, supramolecular layers in the ab plane are sustained by C—H⋯π and π–π interactions [pyrimidine–phenylsulfanyl centroid–centroid distance = 3.8087 (7) Å].

In the title pyrimidine derivative, C 23 H 23 N 3 S 2 , the phenylsulfanyl and benzylsulfanyl benzene rings are orientated away from the carbonitrile group and are twisted out of the plane of the central ring with dihedral angles of 77.66 (6) and 64.73 (5) , respectively. The n-pentyl group has an extended trans conformation. In the crystal, supramolecular layers in the ab plane are sustained by C-HÁ Á Á andinteractions [pyrimidine-phenylsulfanyl centroid-centroid distance = 3.8087 (7) Å ].   Table 1 Hydrogen-bond geometry (Å , ).

Related literature
Cg1 is the centroid of the C6-C11 ring.

Comment
The chemotherapeutic efficacy of pyrimidine derivatives is related to their ability to inhibit vital enzymes responsible for DNA biosynthesis. A large array of pyrimidine non-nucleoside derivatives possess various chemotherapeutic properties.
The molecule of (I), Fig. 1, is a tetra-substituted pyrimidine derivative. With reference to the pyrimidine ring, the S-benzene and benzyl-benzene rings are each twisted out of the plane as indicated in the respective dihedral angles of 77.66 (6) and 64.73 (5)°. The dihedral angle between the benzene rings is 51.74 (6)°, indicating a non-parallel orientation, and they are directed to the same side of the molecule, i.e. away from the carbonitrile group. The n-pentyl group has an extended trans-conformation: the range of torsion angles = 174.92 (10) to -179.41 (12)°.
Weak C-H···π, Table 1, and π-π interactions feature in the crystal packing. The π-π interactions occur between the pyrimidine and S-benzene ring with the separation between the ring centroids being 3.8087 (7) Å [angle between rings = 14.45 (6)° for symmetry operation 3/2 -x, 1/2 + y, 1/2 -z]. The C-H···π interaction involves a methylene-H atom interacting with the benzyl-benzene ring. The interactions lead to supramolecular layers that inter-digitate along the c axis. Globally, the crystal structure comprises alternating pyrimidine-rich and aromatic regions stacking along the c direction.

Experimental
To a solution of 2-(benzylthio)-4-chloro-6-(n-pentyl)pyrimidine-5-carbonitrile (665 mg, 2.0 mmol) in dry pyridine (3 ml) was added thiophenol (220 mg, 2.0 mmol). The mixture was heated for 6 h. On cooling, the solvent was distilled off in vacuo, and water (5 ml) was added to the residue. The precipitate was filtered, washed with cold water, dried and crystallized from ethanol to yield 625 mg (77%)  Carbon-bound H-atoms were placed in calculated positions [C-H 0.95 to 0.99 Å, U iso (H) 1.2 to 1.5U eq (C)] and were included in the refinement in the riding model approximation. One reflection, i.e. (002), was omitted owing to poor agreement. Fig. 1. The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.