4-(4-Chloro-phen-yl)-N-[(E)-4-(dimethyl-amino)-benzyl-idene]-1,3-thia-zol-2-amine.

The title compound, C(18)H(16)ClN(3)S, adopts an extended mol-ecular structure. The thia-zole ring is inclined by 9.2 (1) and 15.3 (1)° with respect to the chloro-phenyl and 4-(dimethyl-amino)-phenyl rings, respectively, while the benzene ring planes make an angle of 19.0 (1)°. A weak inter-molecular C-H⋯π contact is observed in the crystal structure.

3-Ethyl-4-methyl-1H-pyrazol-2-ium-5-olate.

The title compound, C(6)H(10)N(2)O, is a zwitterionic pyrazole derivative. The crystal packing is predominantly governed by a three-center iminium-amine N(+)-H⋯O(-)⋯H-N inter-action, leading to an undulating sheet-like structure lying parallel to (100).

Bis(acetyl-acetonato-κO,O')(pyridine-κN)zinc(II).

In the title compound, [Zn(C(5)H(7)O(2))(2)(C(5)H(5)N)], the metal atom has square-pyramidal coordination geometry with the basal plane defined by the four O atoms of the chelating acetyl-acetonate ligands and with the axial position occupied by the pyridine N atom. The crystal packing is characterized by a C-H⋯O hydrogen-bonded ribbon structure approximately parallel to [10[Formula: see text]].

(2E)-3-(4-Eth-oxy-phen-yl)-1-(2-methyl-4-phenyl-quinolin-3-yl)prop-2-en-1-one monohydrate.

The title hydrate, C(27)H(23)NO(2)·H(2)O, features an almost planar quinoline residue (r.m.s. deviation = 0.015 Å) with the benzene [dihedral angle = 63.80 (7) °] and chalcone [C-C-C-O torsion angle = -103.38 (18)°] substituents twisted significantly out of its plane. The configuration about the C=C bond [1.340 (2) Å] is E. In the crystal, mol-ecules related by the 2(1) symmetry operation are linked along the b axis via water mol-ecules that form O-H⋯O(c) and O-H⋯N(q) hydrogen bonds (c = carbonyl and q = quinoline). A C-H⋯O inter-action also occurs.

(2E)-3-(4-Bromo-phen-yl)-1-(2-methyl-4-phenyl-3-quinol-yl)prop-2-en-1-one.

The conformation about the ethene bond [1.316 (3) Å] in the title compound, C(25)H(18)BrNO, is E. The quinoline ring forms dihedral angles of 67.21 (10) and 71.68 (10)° with the benzene and bromo-substituted benzene rings, respectively. Highlighting the non-planar arrangement of aromatic rings, the dihedral angle formed between the benzene rings is 58.57 (12)°.

1-[2,4,6-Trimethyl-3,5-bis-(4-oxopiperidin-1-ylmeth-yl)benz-yl]piperidin-4-one.

In the structure of the title compound, C(27)H(39)N(3)O(3), each of the (4-oxopiperidin-1-yl)methyl residues adopts a flattened chair conformation (with the N and carbonyl groups being oriented to either side of the central C(4) plane) and they occupy positions approximately orthogonal to the central benzene ring [C(benzene)-C-C(methyl-ene)-N torsion angles 103.4 (2), -104.4 (3) and 71.9 (3)°]; further, two of these residues are oriented to one side of the central benzene ring with the third to the other side. In the crystal packing, supra-molecular layers in the ab plane are sustained by C-H⋯O inter-actions.

Ethyl 2-acetyl-3-(4-bromo-anilino)butanoate.

The title compound, C(14)H(18)BrNO(3), adopts an extended conformation, with all of the main-chain torsion angles associated with the ester and amino groups close to trans. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds are observed.

Diethyl 4-(2,4-dichloro-phen-yl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxyl-ate.

In the title compound, C(19)H(21)Cl(2)NO(4), the dihydro-pyridine ring adopts a flattened boat conformation. The dichloro-phenyl ring is oriented almost perpendicular to the planar part of the dihydro-pyridine ring [dihedral angle = 89.1 (1)°]. An intra-molecular C-H⋯O hydrogen bond is observed. In the crystal structure, mol-ecules are linked into chains along the b axis by N-H⋯O hydrogen bonds.

1-[5-Acetyl-4-(4-bromo-phen-yl)-2,6-dimethyl-1,4-dihydro-pyridin-3-yl]ethanone monohydrate.

The 1,4-dihydro-pyridine ring in the title hydrate, C(17)H(18)BrNO(2)·H(2)O, has a flattened-boat conformation, and the benzene ring is occupies a position orthogonal to this [dihedral angle: 82.19 (16)°]. In the crystal packing, supra-molecular arrays mediated by N-H⋯O(water) and O(water)-H⋯O(carbon-yl) hydrogen bonding are formed in the bc plane. A highly disordered solvent mol-ecule is present within a mol-ecular cavity defined by the organic and water mol-ecules. Its contribution to the electron density was removed from the observed data in the final cycles of refinement and the formula, mol-ecular weight and density are given without taking into account the contribution of the solvent mol-ecule.

Dimethyl 4-(3-hydroxy-phen-yl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxyl-ate.

The 1,4-dihydro-pyridine ring in the title compound, C(17)H(19)NO(5), has a flattened-boat conformation, and the benzene ring is almost orthogonal to it [dihedral angle = 82.98 (12)°]. The hydr-oxy group is disordered over two positions in a 0.780 (4):0.220 (4) ratio. In the crystal, hydrogen-bonding inter-actions of the type N(a)-H⋯O(c) and O(h)-H⋯O(c) (a = amine, c = carbonyl and h = hydr-oxy) link the mol-ecules into a three-dimensional network.

1-{3-[(4-Oxopiperidin-1-yl)carbon-yl]benzoyl}piperidin-4-one.

Two independent mol-ecules comprise the asymmetric unit in the title compound, C(18)H(20)N(2)O(4). One of the mol-ecules exhibits disorder in one of its 4-piperidone rings, which is disposed over two orientations [site occupancy of the major component = 0.651 (5)]. The first independent mol-ecule and the minor component of the second disordered mol-ecule are virtually superimposable. The central four C atoms in the major component of the disordered mol-ecule have an opposite orientation. All the 4-piperidone rings have a chair conformation. The carbonyl groups in each mol-ecule have approximate anti conformations [O=C⋯C=O = 146.2 (2) and -159.9 (2)°]. The 4-piperidone rings lie to opposite sides of the central benzene ring in both mol-ecules. In the crystal, mol-ecules are linked by C-H⋯O inter-actions. The crystal studied was found to be a non-merohedral twin (twin law -1 0 0, 0 1 0, 0 - 1/2 - 1), the fractional contribution of the minor component being approximately 11%.

Hantzsch 1,4-dihydropyridine esters and analogs: candidates for generating reproducible one-dimensional packing motifs.

Examination of the symmetric Hantzsch 1,4-dihydropyridine ester derivatives of the prototypical nifedipine molecule indicates the tendency of this class of molecule to form a common packing motif. Crystal structure analysis of 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylic diesters and analogs reveals that they form extended chains, characterized as the C(6) packing motif, via intermolecular (amine) N-H...O=C (C3,C5 carbonyl) hydrogen bonds. In addition, all the prepared derivatives also satisfy the basic structural requirements for their high binding efficiency to the receptor. The reproducible C(6) packing motif observed among these compounds has a use in the design of solid-state materials.

Ethyl 2-acetyl-3-(4-chloro-anilino)butanoate.

The title compound, C(14)H(18)ClNO(3), adopts an extended conformation, with all of the main chain torsion angles associated with the ester and amino groups trans. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds are observed.

Ethyl 4-(3-hydroxy-phen-yl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexa-hydro-quinoline-3-carboxyl-ate.

In the mol-ecular structure of the title compound, C(21)H(25)NO(4), the dihydro-pyridine ring adopts a flattened boat conformation while the cyclo-hexenone ring is in an envelope conformation. In the crystal structure, mol-ecules are linked into a two-dimensional network parallel to (10) by N-H⋯O and O-H⋯O hydrogen bonds. The network is generated by R(4) (4)(30) and R(4) (4)(34) graph-set motifs.

1,1'-[4-(2-Methoxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-diyl]diethanone.

In the title compound, C(18)H(21)NO(3), the 1,4-dihydro-pyridine ring exhibits a flattened boat conformation. The methoxy-phenyl ring is nearly planar [r.m.s. deviation = 0.0723 (1) Å] and is perpendicular to the base of the boat [dihedral angle = 88.98 (4)°]. Inter-molecular N-H⋯O and C-H⋯O hydrogen bonds exist in the crystal structure.

Tris(methyl 3-oxobutanoato-κO,O')aluminium(III).

In the title compound, [Al(C(5)H(7)O(3))(3)], three acac-type ligands (methyl 3-oxobutanoate anions) chelate to the aluminium(III) cation in a slightly distorted AlO(6) octa-hedral coordination geometry. Electron delocalization occurs within the chelating rings.

1,1'-(p-Phenyl-enedimethyl-ene)dipiperidin-4-one.

In the mol-ecule of the title compound, C(18)H(24)N(2)O(2), the piperidine rings are in chair conformations. The crystal structure is stabilized by inter-molecular C-H⋯O hydrogen bonding. There are neither C-H⋯π nor π-π inter-actions in the structure.

3,3,6,6-Tetra-methyl-9-phenyl-3,4,5,6-tetra-hydro-9H-xanthene-1,8(2H,7H)-dione.

In the title compound, C(23)H(26)O(3), the three six-membered rings of the xanthene system are non-planar, having total puckering amplitudes, Q(T), of 0.443 (2), 0.202 (2) and 0.449 (2) Å. The central ring adopts a boat conformation and the outer rings adopt sofa conformations. The crystal structure is stabilized by van der Waals inter-actions.

Hydrogen-bonded sheets in 2-(2-aminophenyl)-1H-benzimidazol-3-ium dihydrogen phosphate.

The title salt, C(13)H(12)N(3)(+).H(2)PO(4)(-), contains a nonplanar 2-(2-aminophenyl)-1H-benzimidazol-3-ium cation and two different dihydrogen phosphate anions, both situated on twofold rotation axes in the space group C2. The anions are linked by O-H...O hydrogen bonds into chains of R(2)(2)(8) rings. The anion chains are linked by the cations, via hydrogen-bonding complementarities and electrostatic interactions, giving rise to a sheet structure with alternating rows of organic cations and inorganic anions. Comparison of this structure with that of the pure amine reveals that the two compounds generate characteristically different sheet structures. The anion-anion chain serves as a template for the assembly of the cations, suggesting a possible application in the design of solid-state materials.

Adducts of bis(acetylacetonato)zinc(II) with 1,10-phenanthroline and 2,2'-bipyridine.

In each of the zinc(II) complexes bis(acetylacetonato-kappa(2)O,O')(1,10-phenanthroline-kappa(2)N,N')zinc(II), [Zn(C(5)H(7)O(2))(2)(C(12)H(8)N(2))], (I), and bis(acetylacetonato-kappa(2)O,O')(2,2'-bipyridine-kappa(2)N,N')zinc(II), [Zn(C(5)H(7)O(2))(2)(C(10)H(8)N(2))], (II), the metal center has a distorted octahedral coordination geometry. Compound (I) has crystallographically imposed twofold symmetry, with Z' = 0.5. The presence of a rigid phenanthroline group precludes intramolecular hydrogen bonding, whereas the rather flexible bipyridyl ligand is twisted to form an intramolecular C-H...O interaction [the chelated bipyridyl ligand is nonplanar, with the pyridyl rings inclined at an angle of 13.4 (1) degrees]. The two metal complexes are linked by dissimilar C-H...O interactions into one-dimensional chains. The present study demonstrates the distinct effects of two commonly used ligands, viz. 1,10-phenanthroline and 2,2'-bipyridine, on the structures of metal complexes and their assembly.