5-Acetyl-4-(3-hy-droxy-phen-yl)-6-methyl-1,2,3,4-tetra-hydro-pyrimidin-2-one-tris-(hy-droxy-meth-yl)ammonium chloride (2/1).

The asymmetric unit of the title compound, 2C13H14N2O3·C3H10NO3 (+)·Cl(-), contains two independent mol-ecules (A and B) of the title pyrimidine derivative and one ion-pair of tris-(hy-droxy-meth-yl)ammonium chloride. The pyrimidine ring in each pyrimidine derivative has a half-chair conformation. Its mean plane is inclined to the benzene ring by 87.2 (3)° in mol-ecule A and 85.7 (2)° in mol-ecule B. In the crystal, the pyrimidine derivatives are connected to each other by N-H⋯O hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked via O-H-Cl hydrogen bonds, forming corrugated sheets lying parallel to the bc plane. The sheets are linked via C-H⋯O hydrogen bonds, forming a three-dimensional framework. The tris-(hy-droxy-meth-yl)ammonium chloride mol-ecules are located in the cages of the framework. There are also further C-H⋯O hydrogen bonds and C-H⋯π inter-actions present in the three-dimensional framework structure. Both the cation and chloride anion of the tris-(hy-droxy-meth-yl)ammonium chloride ion pair are disordered over two positions, with a refined occupancy ratio of 0.418 (8):0.582 (8) for the cation and 0.71 (4):0.29 (4) for the anion.

10-(2-Pyrid-yloxy)phenanthren-9-ol.

In the title compound, C(19)H(13)NO(2), the pyridyl ring makes a dihedral angle of 87.04 (6)° with the plane of the phenanthrene ring system. In the crystal, mol-ecules are linked through weak inter-molecular C-H⋯O hydrogen bonds and C-H⋯π inter-actions.

Ethyl 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate.

The title compound, C(14)H(16)N(2)O(3), belongs to a group of esters of 2-oxo- and 1,2,3,4-tetra-hydro-pyrimidine-5-carboxylic acids, which exhibit a wide spectrum of biological activities. The dihydro-pyrimidine ring adopts a screw-boat conformation. The crystal packing is stabilized by strong N-H⋯O and weak C-H⋯O inter-molecular hydrogen bonds. An intra-molecular C-H⋯O hydrogen bond is also present.

Ethyl 2-allylsulfanyl-4-(4-methoxyphenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate.

In the title compound, C(18)H(22)N(2)O(3)S, the pyrimidine ring is not planar. It adopts a half-chair conformation The crystal structure is characterized by classical N-H⋯O and C-H⋯O inter- and intra-molecular hydrogen bonds, respectively. The title compound exhibits a wide spectrum of biological activities.

1-Allyl-3,3-diphenyl-indolin-2-one.

In the title compound, C(23)H(19)NO, the oxindole residue is essentially planar and is almost perpendicular to the phenyl rings [dihedral angles = 72.1 (6) and 77.6 (6)°]. The mol-ecular packing is stabilized by C-H⋯O hydrogen bonds and C-H⋯N inter-actions.

1-Allyl-3,3-di-p-tolyl-indolin-2-one.

In the title compound, C(25)H(23)NO, the indoline system is essentially planar. The mol-ecular structure is stabilized by weak intra-molecular C-H⋯N inter-actions and the crystal packing is determined by inter-molecular C-H⋯π inter-actions.