6-[(2-Methyl­phen­yl)sulfan­yl]-5-propyl­pyrimidine-2,4(1H,3H)-dione

In the title pyrimidine-2,4-dione derivative, C₁₄H₁₆N₂O₂S, the dihedral angle between the six-membered rings is 77.81 (10)°. The mol­ecule is twisted about the C_p—S (p = pyrimidine) bond, with a C—S—C—N torsion angle of −59.01 (17)°. An intramolecular C—H...S hydrogen bond generates an S(5) ring motif. In the crystal, bifurcated acceptor N—H...O and C—H...O hydrogen bonds generate inversion-related dimers incorporating R₂¹(9) and R₂²(8) loops. These dimers are connected into a chain extending along the a-axis direction by a second pair of inversion-related N—H...O hydrogen bonds, forming another R₂²(8) loop. The crystal structure is further stabilized by weak inter­molecular C—H...π inter­actions, generating a three-dimensional network.

Crystal structure of 6-chloro-5-iso­propyl­pyrimidine-2,4(1H,3H)-dione

In the mol­ecule of the title compound, C₇H₉ClN₂O₂, the conformation is determined by intra­molecular C—H...O and C—H...Cl hydrogen bonds, which generate S(6) and S(5) ring motifs. The isopropyl group is almost perpendicular to the pyrimidine ring with torsion angles of −70.8 (3) and 56.0 (3)°. In the crystal, two inversion-related mol­ecules are linked via a pair of N—H...O hydrogen bonds into R₂²(8) dimers; these dimers are connected into chains extending along the bc plane via an additional N—H...O hydrogen bond and weaker C—H...O hydrogen bonds. The crystal structure is further stabilized by a weak π–π inter­action [3.6465 (10) Å] between adjacent pyrimidine-dione rings arranged in a head-to-tail fashion, producing a three-dimensional network.