Methyl 4-(4-hy­droxy­phen­yl)-6-methyl-2-sulfanyl­idene-1,2,3,4-tetra­hydro­pyrimidine-5-carboxyl­ate

In the title mol­ecule, C₁₃H₁₄N₂O₃S, the di­hydro­pyrimidine 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 di­hydro­pyrimidine 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 di­hydro­pyrimidine ring. In the crystal, N—H...O and O—H...S hydrogen bonds connect mol­ecules, forming a two-dimensional network parallel to (001).

2-[4-(Tri­fluoro­meth­yl)phen­yl]-1H-benzimidazole

In the title compound, C₁₄H₉F₃N₂, the mean planes of the benzimidazole ring system and the tri­fluoro­methyl-substituted benzene ring form a dihedral angle of 30.1 (1)°. In the crystal, mol­ecules are linked by N—H...N hydrogen bonds into chains along [010]. Weak C—H...F hydrogen bonds and a weak C—H...π inter­action connect the chains into a two-dimensional network parallel to (001).

Crystal structure of ethyl 5-(3-fluoro­phen­yl)-2-[(4-fluoro­phen­yl)methyl­idene]-7-methyl-3-oxo-2H,3H,5H-[1,3]thia­zolo[3,2-a]pyrimidine-6-carboxyl­ate

In the title mol­ecule, C₂₃H₁₈F₂N₂O₃S, the pyrimidine ring is in a half-chair conformation and the 3-fluoro­phenyl group is in the axial position. The thia­zole ring (r.m.s. deviation = 0.0252 Å) forms dihedral angles of 84.8 (7) and 9.6 (7)° with the 3-fluoro-substituted and 4-fluoro-substituted benzene rings, respectively. In the crystal, weak C—H...F and C—H...O hydrogen bonds connect mol­ecules, forming zigzag chains along the b axis. In addition π–π stacking inter­actions with a centroid–centroid distance of 3.7633 (9) Å connect these chains into ladders via inversion-related 4-fluoro­phenyl groups.

Crystal structure of 2-acetyl-5-(3-methoxyphenyl)-3,7-dimethyl-5H-1,3-thiazolo[3,2-a]pyrimidine-6-carboxylate

In the title mol­ecule, C₂₀H₂₂N₂O₄S, the pyrimidine ring is in a flattened half-chair conformation and the 3-meth­oxyphenyl substituent is in an axial arrangement. The thia­zole ring forms a dihedral angle of 81.3 (1)° with the benzene ring. In the crystal, weak C—H...S inter­actions link mol­ecules into chains along [001]. In addition, there are π–π inter­actions between inversion-related thia­zole rings with a centroid–centroid distance of 3.529 (2) Å. The ethyl group was refined as disordered over two sets of sites with an occupancy ratio of 0.52 (3):0.48 (2).

Crystal structure of 1-(2,4-di­methyl­phen­yl)-2-(4-tri­methyl­silyl-1H-1,2,3-triazol-1-yl)ethanone

The asymmetric unit of the title compound, C₁₅H₂₁N₃OSi, contains two mol­ecules with similar conformations (r.m.s. overlay fit for the 20 non-H atoms = 0.163 Å). The dihedral angles between the planes of the 1,2,3-triazole and 2,4-di­methyl­benzene rings are 27.0 (3) and 19.5 (3)°. In the crystal, mol­ecules are linked by very weak C—H...O and C—H...N hydrogen bonds to generate [100] chains. The chains are cross-linked by C—H...π inter­actions.

Crystal structure of ethyl 2-(2-fluoro­benzyl­idene)-5-(4-fluoro­phen­yl)-7-methyl-3-oxo-2,3-di­hydro-5H-1,3-thia­zolo[3,2-a]pyrimidine-6-carb­oxy­late

In the title mol­ecule, C₂₃H₁₈F₂N₂O₃S, the 4-fluoro-substituted and 2-fluoro-substituted benzene rings form dihedral angles of 88.16 (8) and 23.1 (1)°, respectively, with the thia­zole ring. The pyrimidine ring adopts a flattened sofa conformation with the sp³-hydridized C atom forming the flap. In the crystal, pairs of weak C—H...O hydrogen bonds link mol­ecules related by twofold rotation axes, forming R²₂(10) rings, which are in turn linked by weak C—H...N inter­actions to form chains of rings along [010]. In addition, weak C—H...π(arene) inter­actions link the chains into layers parallel to (001) and π–π inter­actions with a centroid–centroid distance of 3.836 (10) Å connect these layers into a three-dimensional network.