Synthesis, crystal structure and Hirshfeld surface analysis of 2-[(4-hy-droxy-phen-yl)amino]-5,5-diphenyl-1H-imidazol-4(5H)-one.

In the title mol-ecule, C21H17N3O2, the five-membered ring is slightly ruffled and dihedral angles between the pendant six-membered rings and the central, five-membered ring vary between 50.78 (4) and 86.78 (10)°. The exocyclic nitro-gen lone pair is involved in conjugated π bonding to the five-membered ring. In the crystal, a layered structure is generated by O-H⋯N and N-H⋯O hydrogen bonds plus C-H⋯π(ring) and weak π-stacking inter-actions.

2-[4-(2-Chloro-benz-yl)-3-methyl-6-oxo-1,6-di-hydro-pyridazin-1-yl]-N-(4-fluoro-phen-yl)acetamide.

The conformation of the title mol-ecule, C20H17ClFN3O2, is partly determined by an intra-molecular C-H⋯O hydrogen bond, which leads to a dihedral angle of 14.7 (4)° between the fluoro-benzene ring and the acetamide group. The 2-chloro-benzyl group is rotationally disordered over two orientations in a 0.656 (2): 0.344 (2) ratio. In the crystal, a layered structure is formed by N-H⋯O, C-H⋯O and C-H⋯F hydrogen bonds plus slipped π-π stacking inter-actions.

3-Methyl-2-(methyl-sulfan-yl)-5,5-diphenyl-3,5-di-hydro-4H-imidazol-4-one.

In the title mol-ecule, C17H16N2OS, the di-hydro-imidazolone ring is slightly puckered and the methyl-sulfanyl group is nearly coplanar with it. In the crystal, two sets of C-H⋯O hydrogen bonds form corrugated layers of mol-ecules parallel to the ac plane. The layers pack with normal van der Waals contacts between them.

15,15-Diphenyl-2,3,4,5,6,8,9,11,12-octa-hydro-imidazo[2,1-h][1,4,12]trioxa[7]thia-[9]azacyclo-tetra-decin-14(15H)-one.

The title mol-ecule, C23H26N2O4S, adopts a cup-shaped conformation. In the crystal, layers lying parallel to the ab plane are formed by C-H⋯O hydrogen bonds and C-H⋯π(ring) inter-actions. The layers stack along the c-axis direction through normal van der Waals inter-actions.

3-(2-Bromo-eth-yl)-5,5-di-phenyl-imidazolidine-2,4-dione.

The imidazolidine ring in the title mol-ecule, C17H15BrN2O2, is slightly ruffled [r.m.s. deviation = 0.0192 Å], while the attached phenyl rings at the C atom at the position between the amine and carbonyl centres are rotated well out of its mean plane [dihedral angles with the imidazolidine ring = 63.60 (8) and 76.4 (1)°]. In the crystal, a three-dimensional network features N-H⋯O and C-H⋯O hydrogen bonds together with C-H⋯π(ring) inter-actions.

3-Isobutyl-5,5-di-phenyl-imidazolidine-2,4-dione.

The imidazolidine ring in the title mol-ecule, C19H20N2O2, is slightly 'ruffled'. In the crystal, a layer structure is generated by N-H⋯O and C-H⋯O hydrogen bonds plus C-H⋯π(ring) inter-actions.

Crystal structure and Hirshfeld surface analysis of 2-chloro-N-(4-meth-oxy-phen-yl)acetamide.

In the title mol-ecule, C9H10ClNO2, the meth-oxy group lies very close to the plane of the phenyl ring while the acetamido group is twisted out of this plane by 28.87 (5)°. In the crystal, a three-dimensional structure is generated by N-H⋯O, C-H⋯O and C-H⋯Cl hydrogen bonds plus C-H⋯π(ring) inter-actions. A Hirshfeld surface analysis of the inter-molecular inter-actions was performed and indicated that C⋯H/H⋯C inter-actions make the largest contribution to the surface area (33.4%).