Biochemie und Chemie
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Mol-ecules of the title compound, [Zn(8)(C(6)F(5))(8)O(4)(C(4)H(10)O)(4)], are located on a special position of site symmetry [Formula: see text]. As a result, there is just one quarter-mol-ecule in the asymmetric unit. The title compound features a Zn(4)O(4) cube. Each Zn atom in the cube carries a pentafluorophenyl substituent. Each O atom is bonded to a further Zn atom, which is connected to a pentafluorophenyl substituent and the O atom of a diethyl ether mol-ecule. All ether C atoms are disordered over two sets of sites with a site occupation factor of 0.51 (2) for the major occupied site.
Molecules of the title compound, C20H14O2, show approximate C s symmetry with the approximate mirror plane perpendicular to the central ring. The torsion angles about the acyclic bonds are 30.05 (15) and 30.77 (15)° in one half compared to −36.62 (14) and −18.60 (15)° in the other half of the molecule. The central aromatic ring makes dihedral angles of 47.78 (4) and 51.68 (3)° with the two terminal rings.
The title compound, C14H20O5S·0.5H2O, crystallizes with two organic molecules and a solvent water molecule in the asymmetric unit. In both molecules, the hexapyranosyl rings adopt a slightly distorted chair conformation (5 C 2) with four substituents in equatorial positions and one substituent in an axial position. The main difference between the organic molecules is the dihedral angle between the phenyl ring and the best plane defined by the O—C1—C2—C3 atoms (r.m.s deviations = 0.003 and 0.043 Å) of the hexapyranosyl rings [47.4 (4) and 86.5 (4)°]. In the asymmetric unit, molecules are linked by two strong O—H[cdots, three dots, centered]O hydrogen bonds. In the crystal, the components are linked by a total of 10 distinct O—H[cdots, three dots, centered]O hydrogen bonds, resulting in the formation of a two-dimensional network parallel to the ab plane.
The title compound, C15H15BrO2, was synthesized by a Brønsted acid-catalysed domino electrocyclization-halogenation reaction. The five-membered ring is essentially planar (r.m.s. deviation 0.006 Å) and forms a dihedral angle of 72.7 (3)° with the attached phenyl ring. The six-membered heterocycle adopts a half-chair conformation. The crystal packing is stabilized by a C—H[cdots, three dots, centered]O contact.
The title compound, C(21)H(18)ClN, was synthesized by an enanti-oselective Brønsted acid-catalysed transfer hydrogenation reaction. The six-membered heterocycle adopts a half-chair conformation. It has the biphenyl residue in an axial position. The two rings of the biphenyl residue are almost coplanar [dihedral angle = 2.65 (9)°]. The crystal packing is stabilized by N-H⋯Cl hydrogen bonds, which connect the mol-ecules into chains running along the a axis.
The title compound, C25H20N4O2, is a ditopic ortho-hydroquinone-based bis(pyrazol-1-yl)methane ligand. The dihedral angles between the planes of the pyrazole rings and their attached phenyl rings are 17.4 (3) and 5.9 (4)°. The pyrazole rings make a dihedral angle of 87.84 (16)°. One of the two hydroxy groups forms an intramolecular hydrogen bond to the other hydroxy group, whereas the second is involved in an intermolecular O—H[cdots, three dots, centered]N hydrogen bond. As a result of these intermolecular hydrogen bonds, helical chains running along the b axis are formed.
The fused five- and six-membered rings in the title compound, C14H12N2O, are essentially planar, the largest deviation from the mean plane being 0.023 (2) Å. The dihedral angle between the benzimidazole mean plane and the phenyl ring is 68.50 (6)°. In the crystal, each molecule is linked to its symmetry equivalent created by a crystallographic inversion center by pairs of N—H[cdots, three dots, centered]O hydrogen bonds, forming inversion dimers.
In the mol-ecule of the title compound, C(12)H(12)BrN(3)O, the fused-ring system is essentially planar, the largest deviation from the mean plane being 0.0148 (3) Å. The two allyl groups are nearly perpendicular to the imidazo[4,5-b]pyridine plane [C-C-N-C torsion angles of 81.6 (4) and -77.2 (4)°] and point in the same direction. The planes through the atoms forming each allyl group are nearly perpendicular to the imidazo[4,5-b]pyridin-2-one system, as indicated by the dihedral angles between them of 80.8 (5) and 73.6 (5)°.
The two fused five- and six-membered rings building the molecule of the title compound, C13H10BrN3, are approximately planar, the largest deviation from the mean plane being 0.004 (2) Å. The dihedral angle between the imidazo[4,5-b]pyridine mean plane and that of the phenyl ring is 41.84 (11)°. The structure is held together by slipped π–π stacking between symmetry-related molecules, with an interplanar distance of 3.583 (1) Å and a centroid–centroid vector of 3.670 (2) Å.
The structure of the title compound, (C15H15N2O4)[AgI2], consists of an organic 4-[3-(isonicotinoyloxy)propoxycarbonyl]pyridinium cation which has a gauche–gauche (O/C/C/C—O/C/C/C or GG’) conformation and lies on a twofold rotation axis, which passes through the central C atom of the aliphatic chain, and an inorganic [AgI2]− anion. In the complex anion, the Ag+ cation is bound to two I− anions in a linear geometry. The anion was modelled assuming disorder around a crystallographic inversion centre near the location of the Ag+ cation. The crystal packing is stabilized by a strong intermolecular N—H[cdots, three dots, centered]N hydrogen bond, which links the cations into zigzag chains with graph-set notation C(16) running along the face diagonal of the ac plane. The N-bound H atom is disordered over two equally occupied symmetry-equivalent sites, so that the molecule has a pyridinium ring at one end and a pyridine ring at the other.