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1.
Sabahat
zcan Engin Kendi Meral Tunbilek Hakan Gker 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):459-460
The title compound, C21H23ClN4O2·0.5H2O, contains two independent molecules in the asymmetric unit. In each molecule the piperazine ring adopts a chair conformation; the deviations of the piperazine N atoms from the best plane through the remaining four C atoms are ?0.678 (3) and 0.662 (3) Å in molecule A, and 0.687 (3) and ?0.700 (3) Å in molecule B. The molecules are linked by two hydrogen bonds of the O—H?N type involving the O atom of the water molecule of crystallization. 相似文献
2.
Bernardo Masci Martine Nierlich Pierre Thury 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o86-o87
2,3,6,7‐Tetrahydroxy‐9,10‐dimethyl‐9,10‐dihydro‐9,10‐ethanoanthracene crystallizes with 1,4‐dioxane to give a bis‐solvate, C18H18O4·2C4H8O2. The bis(catechol) molecule is located on a twofold axis and the two aromatic rings form a dihedral angle of 130.61 (4)°. Hydrogen bonds are formed between the hydroxyl groups and either a neighbouring bis(catechol) molecule or the ether‐O atom of a dioxane molecule. 相似文献
3.
Robert W. Janes 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):362-364
The title compound, C9H8FN5·C3H7NO, contains two independent complexes in the asymmetric unit, each consisting of one 3,5‐diamino‐6‐(2‐fluorophenyl)‐1,2,4‐triazine molecule and one dimethylformamide solvent molecule. One triazine molecule is disordered over two conformations within the crystal, the occupancies being 62 (1) and 38 (1)%. The phenyl ring of this molecule resolves into two conformations rotated by almost 180° about the bridging bond between the two rings, while the triazine rings approximately superimpose on each other. The triazine molecules of the asymmetric unit differ in the dihedral angles between their respective phenyl and triazine ring planes, these being 57.6 (2)° for the fully occupied, and 76.9 (6) and 106.8 (8)° for the partially occupied molecules. An extensive network of hydrogen bonds maintains the crystal structure. 相似文献
4.
Viktor Kettmann Jan Lokaj Christoph Kratky Viktor Milata Pavol Hodul 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1007-1008
In the title compound, C14H15N3O4·H2O, there is a strong conjugation push–pull effect across the central double bond, as reflected in the molecular dimensions and the planarity of the enaminone portion of the molecule. The molecule has an intramolecular hydrogen bond between the NH and CO groups in the Z configuration, adopting the chelated form. The two π systems of the molecule (1‐methylbenzimidazole and enaminone) are deconjugated and tilted with respect to each other by 15.6 (2)°. The solvent water molecule is hydrogen bonded to the N1 atom of the 1‐methylbenzimidazolyl group. 相似文献
5.
Jarmila Duskova Jiri Labsky Ivana Cisarova Tereza Skalova Jan Dohnalek Jindrich Hasek 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o563-o566
The asymmetric unit of the title compound, C11H5D16N2O2·0.33H2O, is formed by three crystallographically independent piperidin‐1‐yloxyl molecules and a molecule of water. The molecules are crosslinked by nine hydrogen bonds into layers parallel with the ac plane. The water molecule contributes to the stability of the low‐symmetry arrangement by four hydrogen bonds. 相似文献
6.
Viktor Kettmann Jan Lokaj Viktor Milata Milan Marko Magdalna tvrteck 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o252-o254
In the title compound, C13H13NO2, there is polarization of π‐electron density from the amine N atom to the acceptor carbonyl groups: as a result, the molecule exists predominantly in an azomethino‐1,3‐diketone tautomeric form. There is crystallographic evidence that the phenyl ring, although roughly coplanar with the rest of the molecule, is deconjugated with the adjacent π system of the molecule. The cyclohexane ring adopts an unsymmetrical half‐chair conformation and converts between two inversion‐related conformers. The molecule is stabilized by an intramolecular hydrogen bond, while the intermolecular packing is dominated by a number of short C—H⋯O contacts. 相似文献
7.
Chao Tu Dun‐Ru Zhu Yan Xu Xiao‐Kang Ke Zijian Guo 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1334-1335
The title compound, C11H8N2O, has two crystallographically independent molecules in the crystal. Each molecule is basically planar except for the O atom. The two N atoms in the molecule show different behaviour as hydrogen‐bonding acceptors. One of them is involved in intermolecular O—H?N hydrogen bonds which stabilize the crystal packing. 相似文献
8.
Lamine Hamdellou Olivier Hernandez Jean Meinnel 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o557-o560
The structures of 4‐dimethylamino‐β‐nitrostyrene (DANS), C10H12N2O2, and 4‐dimethylamino‐β‐ethyl‐β‐nitrostyrene (DAENS), C12H16N2O2, have been solved at T = 100 K. The structure solution for DANS was complicated by the presence of a static disorder, characterized by a misorientation of 17% of the molecules. The molecule of DANS is almost planar, indicating significant conjugation, with a push–pull effect through the styrene skeleton extending up to the terminal substituents and enhancing the dipole moment. As a consequence of this conjugation, the hexagonal ring displays a quinoidal character; the lengths of the C—N [1.3595 (15) Å] and C—C [1.448 (2) Å] bonds adjacent to the benzene ring are shorter than single bonds. The molecules are stacked in dimers with antiparallel dipoles. In contrast, the molecule of DAENS is not planar. The ethyl substituent pushes the nitropropene group out of the benzene plane, with a torsion angle of −21.9 (3). Nevertheless, the molecule remains conjugated, with a shortening of the same bonds as in DANS. 相似文献
9.
Bernadette Suchod Olivier Stphan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):e92-e93
The central part of the title molecule, C50H66, is planar, all the rings being in the same plane; the lateral chains are also planar (excluding H atoms), almost perpendicular to the ring plane and grafted on the same side of the molecule. The molecule has nearly a mirror plane, perpendicular to the central C—C bond, instead of the centre of symmetry expected. The orientation of the plane of the rings is approximately 45° from the unit‐cell b axis, so that neighbouring molecules are essentially perpendicular. 相似文献
10.
Muharrem Diner Namk
zdemir M. Emin Günay Bekir etinkaya Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):m373-m375
The title complex, [RhBr(C8H12)(C19H22N2O2)], has a distorted square‐planar geometry. There are two molecules, A and B, in the asymmetric unit. The Rh—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.039 (2) Å in molecule A and 2.042 (2) Å in molecule B. The angle between the carbene heterocycle and the coordination plane is 87.56 (12)° in molecule A and 87.03 (11)° in molecule B. It is shown that the average Rh—C(COD) (COD is cyclooctadiene) distance is linearly dependent on the Rh—C(imidazolidine) distance in this type of compound. This can be ascribed to the steric hindrance produced by the packing. The crystal structure contains intramolecular C—H⋯O and intermolecular C—H⋯Br interactions. 相似文献
11.
Raffaella Soave Riccardo Destro 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o507-o509
The asymmetric unit of the title compound, C22H31N3O4·H2O, incorporates one water molecule, which is hydrogen bonded to the 3‐oxo O atom of the indolizidinone system. The two rings of the peptidomimetic molecule are trans‐fused, with the six‐membered ring having a slightly distorted half‐chair conformation and the five‐membered ring having a perfect envelope conformation. The structure is stabilized by intermolecular O—H?O interactions between the water and adjacent peptide molecules, and by N—H?O interactions between the peptide molecules, which link the molecules into infinite chains. 相似文献
12.
Eleonora Freire Sergio Baggio Juan Carlos Muoz Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m299-m301
The structure of the title compound, [Ni(ths)(bbip)(dmf)]·H2O [ths is thiosulfate, S2O3; bbip is 2,6‐bis(1H‐benzimidazol‐2‐yl)pyridine, C21H13N5; and dmf is dimethylformamide, C3H7NO], is monomeric, with the nickel ion octahedrally surrounded by an N,N′,N′′‐tridentate bbip molecule, an S,O‐bidentate ths molecule and an O‐monodentate dmf molecule. The H atoms of the hydration water molecule and the amino groups of bbip are involved in hydrogen bonding and determine a spatial organization of broad layers parallel to (001), which are connected by weak interactions. 相似文献
13.
A. Subbiah Pandi D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun M. C. Bansal 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o302-o304
The title compound, C19H20O6, crystallizes in the centrosymmetric space group P21/c with one molecule in the asymmetric unit. The molecule is approximately planar and the dihedral angle between the phenyl rings is 11.0 (1)°. The H atoms of the central propenone group are trans. There is an intramolecular O—H⃛O hydrogen bond and the molecules are crosslinked by four intermolecular C—H⃛O hydrogen bonds, producing a three‐dimensional network. 相似文献
14.
L. C. R. Andrade J. A. Paixo M. J. M. de Almeida C. Siquet F. Borges 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):o95-o97
The molecule of the title compound, C23H40O4Si2, features an approximate non‐crystallographic C2 symmetry axis. The aldehyde group is disordered over two positions with similar occupancies. The geometry of the isolated molecule was studied by ab initio quantum mechanical calculations employing a molecular orbital Hartree–Fock method. The calculations reproduce well the equilibrium geometry but slightly overestimate the value of the Si—O bond lengths of the trioxadisilepine ring. 相似文献
15.
Pance Naumov Frosa Anastasova Michael G. B. Drew Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):e406-e407
In the title compound (5‐fluoroisatin), C8H4FNO2, the N atom of one molecule is linked to the amido‐O atom of an adjacent molecule across a center of symmetry by a cyclic hydrogen bond [N?O = 2.888 (4) Å]. 相似文献
16.
Cem Cüneyt Ersanl idem Albayrak Mustafa Odabaolu Carsten Thne Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o133-o135
The structure of the title compound, C18H20ClN3O5, displays the characteristic features of azobenzene derivatives. Intramolecular N—H⋯O, weak intramolecular C—H⋯O, and intermolecular O—H⋯O and C—H⋯O interactions influence the conformation of the molecules and the crystal packing. Intermolecular hydrogen bonds link the molecules into infinite chains, and the title compound adopts the keto–amine tautomeric form. The azobenzene moiety of the molecule has a trans configuration. The molecule is not planar, and the dihedral angle between the two phenyl rings is 35.6 (2)°. 相似文献
17.
A. Abdul Ajees S. Parthasarathy S. Manikandan R. Raghunathan 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):473-475
The title compound, C23H15Cl2NO3, crystallizes with two independent molecules in the asymmetric unit. The chromanone moiety consists of a benzene ring fused with a six‐membered heterocyclic ring which adopts a sofa conformation. The five‐membered spiroisoxazoline ring is in an envelope conformation. The p‐chlorophenyl rings bridged by the five‐membered ring are nearly perpendicular to each other. The chromanone moiety of one molecule packs into the cavity formed by the p‐chlorophenyl rings of a second molecule through the formation of C—H?π interactions. The structure is stabilized by weak C—H?O, C—H?Cl and C—H?π interactions. 相似文献
18.
Christophe Faulmann Anthony E. Pullen 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o338-o340
The title compound, C10H12O6S, has been obtained as dark‐yellow chunk‐shaped crystals, together with the expected thin white needles. The structures of the two phases are identical. Two independent molecules compose the asymmetric unit: one molecule is totally planar, whereas a methyl group of the second molecule points out of the plane. Each molecule participates in several intra‐ and intermolecular hydrogen bonds and short contacts. The overall structure can be regarded as parallel sheets of molecules. Within a sheet, molecules are connected to one another in an infinite network via numerous short intermolecular contacts. Sheets are connected via hydrogen bonds and short contacts, in particular involving the methyl groups. 相似文献
19.
John N. Low Debbie Cannon Antonio Quesada Antonio Marchal Manuel Melguizo Manuel Nogueras Adolfo Snchez Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):604-607
In the title compound, 2C10H15N5O4·0.5H2O, there are two independent molecules of the pyrimidinylisoleucine in general positions and a water molecule lying on a twofold rotation axis. The bond lengths within the organic moieties demonstrate significant polarization of the electronic structure. Each of the organic molecules participates in 12 intermolecular hydrogen bonds, of O—H?O and N—H?O types, while the water molecule acts as a double donor and as a double acceptor of O—H?O hydrogen bonds. The organic components are linked by the hydrogen bonds into a single three‐dimensional framework, reinforced by the water molecules. 相似文献
20.
Alexander B. Zolotoy Mark Botoshansky Menahem Kaftory John R. Scheffer Jie Yang 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o220-o222
The title compound, C17H14N2S, crystallizes in a triclinic unit cell, with two crystallographically independent molecules in the asymmetric unit. The two independent molecules pack in the same sense and form segregated layers along the c axis. The crystal is light‐stable and no dimers are formed under irradiation. The intermolecular distances between the potential reactive centers (the C‐3 and C‐5 ring positions) are 4.093 (4) and 5.643 (4) Å for molecule A, and 4.081 (4) and 5.614 (4) Å for molecule B. 相似文献