In the title compound, C(32)H(37)NO(3), the central dihydro-pyridine ring adopts a nearly planar flattened-boat conformation, whereas both cyclo-hexenone rings adopt half-chair conformations. The mean and maximum deviations from the mean plane of the dihydro-pyridine ring are 0.1252 (9) and 0.188 (1) Å, respectively. The 4-eth-oxy-phenyl and phenyl rings form dihedral angles of 75.20 (4) and 82...

Chelidamic acid (4-hy-droxy-pyridine-2,6-dicarb-oxy-lic acid) and 2,6-diamino-pyridine react to form the title salt, C(5)H(8)N(3) (+)·C(7)H(4)NO(5) (-); there are two formula units in the asymmetric unit. The pyridine N atom of 2,6-diamino-pyridine is protonated whereas chelidamic acid is deprotonated at both carboxyl-ate groups but protonated at the N atom; the reaction involves intra- and int...

Azacalix[5]pyridine, a heteroatom bridged calixaromatic with an odd number of arene units, and azacalix[10]pyridine, a giant molecular belt, were selectively synthesized based on a 2 + 3 macrocyclic coupling strategy; both novel macrocyclic hosts formed strong 1 : 1 complexes with fullerenes C60 and C70 in a size-selective manner with association constants up to 1.3 x 10(5) +/- 0.03 x 10(5) M(-1).

Natural products that target the RNA components of bacterial ribosomes and thereby act as antibiotics that shut down microbial protein synthesis, have provided a rich source of inspiration for the design and synthesis of small-molecule ligands directed at RNA targets. 2] A prominent example of a privileged scaffold for RNA recognition occurring in natural aminoglycoside antibiotics is 2-deoxyst...

In the title compound, {[Ce(C(14)H(9)N(2)O(5))(C(14)H(8)N(2)O(5))(H(2)O)(2)]·H(2)O}(n), three carboxyl groups of two independent isophthalate anions are deprotonated and they bridge the Ce(III) cations, forming a two-dimensional polymeric structure parallel to (001); another carboxyl group is not deprotonated and links with the adjacent pyridine ring via an O-H⋯N hydrogen bond. The Ce(III) cati...

A previous study of substituent effects on the photo-cleavage of 1-acyl-7-nitroindolines has been extended to examine the effects of electron-donating and electron-withdrawing substituents. 1-Acetyl-4,5-methylenedioxy-7-nitroindoline was inert to 350 nm irradiation, reinforcing an earlier finding that excessive electron-donation by substituents can divert the excited state into non-productive p...

In the structure of the title compound, [Co(C(10)H(5)F(4)O(2))(2)(C(5)H(5)N)(2)], cobalt(II) forms a complex with two 4,4,4-trifluoro-1-(4-fluoro-phen-yl)butane-1,3-dionate anions and two pyridine mol-ecules in an octa-hedral coordination environment, where the two dionate ligands are in equatorial positions and the two pyridine mol-ecules in axial positions. The complex is located on a crystal...

The title compound, [U(C(5)H(7)O(2))(2)O(2)(C(6)H(6)N(2)O)], exhibits a penta-gonal-bipyramidal coordination geometry around the U(VI) atom, involving two bidentate acetyl-acetonate ions and the pyridine ring of the pyridine-4-carbaldehyde oxime ligand. Hydrogen bonds exist between the OH group of the pyridine-4-carbaldehyde oxime ligand and the two O atoms of the acetyl-acetonate ions.

The title compound, C(19)H(9)N(5)O(4), has crystallographically imposed twofold rotational symmetry. The asymmetric unit contains one half-mol-ecule. The crystal structure is stabilized by π-π stacking of inversion-related pyrrolo-[3,4-b]pyridine rings, with a centroid-centroid distance between stacked pyridines of 3.6960 (8) Å. The dihedral angle between the central pyridine ring and the pyrro...