Methyl 4-(4-hy-droxy-phen-yl)-6-methyl-2-sulfanyl-idene-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate.

In the title mol-ecule, C13H14N2O3S, the di-hydro-pyrimidine ring is in a flattened sofa conformation, with the methine C atom forming the flap. The dihedral angle between the mean plane of the five essentially planar atoms of the di-hydro-pyrimidine ring [maximum deviation = 0.056 (4) Å] and the benzene ring is 89.4 (2)°. The O atom of the carbonyl group is in a trans conformation with respect to the C=C bond of the di-hydro-pyrimidine ring. In the crystal, N-H⋯O and O-H⋯S hydrogen bonds connect mol-ecules, forming a two-dimensional network parallel to (001).

Methyl 5-(4-acet-oxy-phen-yl)-2-(2-bromo-benzyl-idine)-7-methyl-3-oxo-2,3-di-hydro-5H-1,3-thia-zolo[3,2-a]pyrimidine-6-carboxyl-ate.

In the title mol-ecule, C24H19BrN2O5S, the pyrimidine ring is in a flattened half-chair conformation and the 4-acet-oxy-phenyl group is substituted axially to this ring. The thia-zole ring is essentially planar [with a maximum deviation of 0.012 (2) Šfor the N atom] and forms dihedral angles of 17.65 (13) and 88.95 (11)° with the bromo- and acet-oxy-substituted benzene rings, respectively. The dihedral angle between the benzene rings is 81.84 (13) Å. In the crystal, pairs of weak C-H⋯O hydrogen bonds lead to the formation of inversion dimers. A weak C-H⋯π inter-action and π-π stacking inter-actions with centroid-centroid distances of 3.5903 (14) Šare observed.

6-Chloro-3-[(di-methyl-amino)-methyl-idene]thio-chroman-4-one.

The asymmetric unit of the title compound, C12H12ClNOS, contains three independent mol-ecules, with the thio-chroman ring adopting a sofa conformation in each one. The crystal structure features C-H⋯O inter-actions; one of the O atoms accepts three such bonds. Together, the hydrogen bonds give rise to a molecular tape propagating in [010].

2-[4-(Trifluoro-meth-oxy)phen-yl]-1H-benzimidazole.

In the title compound, C(14)H(9)F(3)N(2)O, the best planes of the benzimidazole group and benzene ring form a dihedral angle of 26.68 (3)°. In the crystal, N-H⋯N hydrogen bonds link the mol-ecules into infinite chains parallel to the c axis. Stacking inter-actions between the benzimidazole groups [centroid-centroid distance = 3.594 (5) Å] assemble the mol-ecules into layers parallel to (100). The trifluoro-methyl group is disordered over three sets of sites with site-occupancy factors of 0.787 (4), 0.107 (7) and 0.106 (7).

2-(3,4-Di-fluoro-phen-yl)-1H-benzimidazole.

In the title mol-ecule, C13H8F2N2, the dihedral angle between the benzimidazole ring system and the di-fluoro-substituted benzene ring is 30.0 (1)°. In the crystal, mol-ecules are linked by N-H⋯N hydrogen bonds, forming chains along [010]. In addition, weak C-H⋯F hydrogen bonds connect chains into a two-dimensional network parallel to (001). A weak C-H⋯π inter-action is observed between an H atom of the benzimidazole ring sytem and the π system of the di-fluoro-substituted benzene ring.

2-Amino-4-methyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile.

In the title compound, C(10)H(12)N(2)S, the thio-phene ring is essentially planar (r.m.s. deviation = 0.0290 Å). The two C atoms of the cyclo-hexene ring (at positions 6 and 7) are disordered over two sets of sites in a 0.810 (5):0.190 (5) ratio. The cyclo-hexene rings in both the major and minor occupancy conformers adopt a half-chair conformation. In the crystal, there are two types of N-H⋯N inter-action. One of these results in centrosymmetric head-to-head dimers corresponding to an R(2) (2)(12) graph-set motif and the other forms a 20-membered macrocyclic ring involving six mol-ecules.

4-Imino-2,7-dimethyl-5,6,7,8-tetra-hydro-4H-1-benzothieno[2,3-d]pyrimidin-3-amine.

In the title compound, C(12)H(16)N(4)S, the fused benzothio-phene and the pyrimidine rings are coplanar [dihedral angle = 1.61 (6)°]. Three C atoms of the cyclohexene ring (at positions 3, 6 and 7) are disordered over two sites with an occupancy ratio of 0.702 (8):0.298 (8). The cyclo-hexene ring in both the major and minor components adopts a half-chair conformation. The crystal structure is stabilized by N-H⋯N and C-H⋯N inter-actions, resulting in the formation of inversion dimers with R(2) (2)(10) and R(2) (2)(12) graph-set motifs.

1-(2-Chloro-eth-yl)-1H-pyrazolo-[3,4-d]pyrimidin-4(5H)-one.

In the title compound, C(7)H(7)ClN(4)O, the pyrazolo-pyrimidine ring is essentially planar, the r.m.s. deviation of the fitted atoms being 0.0071 Å. The crystal structure features strong N-H⋯O hydrogen bonds and further consolidated by weak C-H⋯O, C-H⋯N and C-H⋯Cl inter-actions.

Ethyl 3-acetyl-4-(3-meth-oxy-phen-yl)-6-methyl-2-sulfanyl-idene-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate.

In the title compound, C(17)H(20)N(2)O(4)S, the aryl ring is positioned perpendicular to the dihydro-pyrimidine ring, the dihedral angle between the ring planes being 77.48 (9)°. The carboxyl-ate and methyl groups are in a cis conformation with respect to the C=C bond. The dihydro-pyrimidine ring adopts a twist-boat conformation. The crystal structure is stabilized by N-H⋯O and C-H⋯O inter-actions, the former resulting in mol-ecular chains along the b axis and the latter forming inversion dimers.

Methyl 2-(2-bromo-benzyl-idene)-5-(4-hy-droxy-phen-yl)-7-methyl-3-oxo-2,3-dihydro-5H-1,3-thia-zolo[3,2-a]pyrimidine-6-carboxyl-ate.

In the title compound, C(22)H(17)BrN(2)O(4)S, the central dihydropyrimidine ring, with a chiral C atom, is significantly puckered and adopts a half-chair conformation with the chiral C atom displaced from the mean plane of the remaining ring atoms by 0.305 (6) Å. The hydroxy-phenyl ring is positioned axially to the pyrimidine ring and almost bisects it, the dihedral angle between the mean-planes of the two rings being 89.78 (12)°. The meth-oxy-carbonyl group is disordered over two sites with an occupancy ratio of 0.568 (5):0.432 (5), resulting in a major and a minor conformer. In the crystal, O-H⋯N and C-H⋯S inter-actions result in sheets along the c axis. The supra-molecular assembly is stabilized by π-π stacking inter-actions between the 2-bromo-benzyl-idene and thia-zolopyrimidine rings [centroid-centroid distance = 3.632 (1) Å]. In addition, C-H⋯π inter-actions are also observed in the crystal structure.

2-Phenyl-8,9,10,11-tetra-hydro-1-benzo-thieno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine.

In the title compound, C(17)H(14)N(4)S, the benzothieno moiety is fused at one end of the pyramidine ring while the triazole ring with a phenyl substituent is fused at the other side. The triazole ring is almost planar [maximum deviation = 0.0028 (3) Å] while the cyclo-hexane ring adopts a half-chair conformation. In the crystal, pairs of inter-molecular C-H⋯N hydrogen bonds form centrosymmetric head-to-head dimers, corresponding to an R(2) (2)(8) graph-set motif. Further C-H⋯N inter-actions generate a zigzag chain of mol-ecules along the c axis. The supra-molecular assembly is consolidated by π-π stacking inter-actions [centroid-centroid distance = 3.445 (4) Å].