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1.
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
2.
Manfredo Hrner Leandro Bresolin Jairo Bordinhao Edmund Hartmann Joachim Strhle 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):o426-o427
The structure of the title compound, C12H9N5O4, reveals an almost planar molecule (r.m.s. deviation = 0.061 Å), in which the interplanar angle between the phenyl rings is 5.7 (1)° and the largest interplanar angle is that between the phenyl ring and the nitro group of one of the 4‐nitrophenyl substituents [8.8 (3)°]. The observed molecular conformation suggests a delocalization of π‐electrons extended over the diazoamine group and the terminal aryl substituents. Intermolecular N—H⃛O interactions between the twofold screw‐related molecules give rise to helical chains along the [010] direction. Intermolecular C—H⃛O interactions then generate sheets of molecules in the (10) plane, and these sheets are held together by N⃛C and O⃛O π–π interactions. 相似文献
3.
T. Ravishankar K. Chinnakali N. Arumugam P. C. Srinivasan Anwar Usman Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o137-o140
In the title compound, C24H20Br2N2O4S, the indole ring system is planar and the S atom has a distorted tetrahedral configuration. The sulfonyl‐bound phenyl ring is orthogonal to the indole ring system and the conformation of the phenylsulfonyl substituent with respect to the indole moiety is influenced by intramolecular C—H⃛O hydrogen bonds involving the two sulfonyl O atoms. The mean plane through the acetylamido group makes a dihedral angle of 57.0 (1)° with the phenyl ring of the benzyl moiety. In the crystal, glide‐related molecules are linked together by N—H⃛O hydrogen bonds and C—H⃛π interactions to form molecular chains, which extend through the crystal. Inversion‐related chains are interlinked by C—H⃛π interactions to form molecular layers parallel to the bc plane. These layers are interconnected through π–π interactions involving the five‐ and six‐membered rings of the indole moiety. 相似文献
4.
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
5.
Manuela Ramos Silva Ana Matos Beja Susana H. Lopes Jos Antnio Paixo Abílio J. F. N. Sobral A. M. d'A. Rocha Gonsalves 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o685-o687
In the title compound, C16H17NO3·H2O, the pyrrole ring is distorted slightly from ideal C2v symmetry. Three strong hydrogen bonds link the substituted pyrrole and water molecules to form infinite chains, in which the hydrogen bonds form rings and chain patterns. Two intermolecular C—H?π interactions maintain the internal cohesion between these chains. The molecular structure differs slightly from that of the isolated molecule calculated by ab initio quantum‐mechanical calculations. In the latter model, the non‐H substituent atoms share the plane of the pyrrole ring, except for the phenyl group, which lies almost perpendicular to this plane. 相似文献
6.
Srinivasulu Aitipamula Ashwini Nangia Ram Thaimattam Mariusz Jasklski 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):o481-o484
In tris(4‐hydroxyphenyl)methane (or 4,4′,4′′‐methanetriyltriphenol), C19H16O3, molecules are connected by O—H⃛O hydrogen bonds [O⃛O = 2.662 (2) and 2.648 (2) Å] into two‐dimensional square networks that are twofold interpenetrated. In tris(4‐hydroxyphenyl)methane–4,4′‐bipyridine (1/1), C19H16O3·C10H8N2, trisphenol molecules form rectangular networks via O—H⃛O [O⃛O = 2.694 (3) Å] and C—H⃛O [C⃛O = 3.384 (3) Å] hydrogen bonds. Bipyridine molecules hydrogen bonded to phenol moieties [O⃛N = 2.622 (3) and 2.764 (3) Å] fill the voids to complete the structure. 相似文献
7.
Michael Lewis Charles L. Barnes Rainer Glaser 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):393-396
The crystal structure of the title mixed azine, C17H17ClN2O, contains four independent molecules, A–D, and molecule B is disordered. All four molecules have an N—N gauche conformation, with C—N—N—C torsion angles of 136.5 (4), 137.0 (4), ?134.7 (4) and ?134.7 (4)°, respectively. The phenyl rings are also somewhat twisted with respect to the plane defined by Cipso and the imine bond. On average, the combined effect of these twists results in an angle of 64.7° between the best planes of the two phenyl rings. Arene–arene double T‐contacts are the dominant intermolecular interaction. The methoxy‐substituted phenyl ring of one azine molecule interacts to form a T‐contact with the methoxy‐substituted phenyl ring of an adjacent molecule and, similarly, two chloro‐substituted phenyl rings of neighboring molecules interact to form another T‐contact. The only exception is for molecule B, for which the disorder leads to the formation of T‐contacts between methoxy‐ and chloro‐substituted phenyl rings. The prevailing structural motif of T‐contact formation between like‐substituted arene rings results in a highly dipole‐parallel‐aligned crystal structure. 相似文献
8.
Mario Cetina Senka ?akovi Vladimir Rapi Amalija Golobi
《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m328-m330
In the title compound, [Fe(C5H5)(C14H13O)], the plane of the heterocyclic ring is almost perpendicular to the plane of the substituted cyclopentadienyl ring, and the heterocyclic ring adopts a half‐chair conformation. The conformation of the nearly parallel cyclopentadienyl (Cp) rings [the dihedral angle between their planes is 2.7 (1)°] is almost halfway between eclipsed and staggered, and the rings are mutually twisted by about 19.4 (2)° (mean value). The mean lengths of the C—C bonds in the substituted and unsubstituted cyclopentadienyl ring are 1.420 (2) and 1.406 (3) Å, respectively, and the Fe—C distances range from 2.029 (2) to 2.051 (2) Å. The phenyl and unsubstituted cyclopentadienyl rings are involved in C—H⃛π interactions, with intermolecular H⃛centroid distances of 2.85 and 3.14 Å for C—H⃛π(Ph), and 2.88 Å for C—H⃛π(Cp). In two of these interactions, the C—H bond points towards one of the ring bonds rather than towards the ring centroid. In the crystal structure, the C—H⃛π interactions connect the molecules into a three‐dimensional framework. 相似文献
9.
Jos Antnio Paixo Manuela Ramos Silva Ana Matos Beja Abílio J. F. N. Sobral Susana H. Lopes A. M. d'A. Rocha Gonsalves 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):o721-o723
In the title compound, C15H17NO2, the ethoxycarbonyl group is anti with respect to the pyrrole N atom. The angle between the planes of the phenyl and pyrrole rings is 48.26 (9)°. The molecules are joined into dimeric units by a strong hydrogen bonds between pyrrole N—H groups and carbonyl O atoms. The geometry of the isolated molecule was studied by ab initio quantum mechanical calculations, employing both molecular orbital Hartree–Fock (MO–HF) and density functional theory (DFT) methods. The minimum energy was achieved for a conformation where the angle between the planes of the phenyl and pyrrole rings is larger, and that between the ethoxycarbonyl and pyrrole planes is smaller than in the solid‐state molecule. 相似文献
10.
Lei Wang Yong Zhang Cheng‐Rong Lu De‐Chun Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o696-o698
In the molecule of the title compound, C16H13BrO, the two benzene rings are rotated in opposite directions with respect to the central C—C=C—C part of the molecule. The phenone O atom deviates from the least‐squares plane of the molecule by 0.300 (3) Å. In the crystal structure, molecules are paired through C—H⋯π interactions. The molecular pairs along [001] are hydrogen bonded through three translation‐related co‐operative hydrogen bonds in the `bay area', forming molecular chains, which are further hydrogen bonded through C—H⋯Br weak interactions, forming (010) molecular layers. In the third direction, there are only weak van der Waals interactions. The co‐operative hydrogen bonds in the `bay area' are discussed briefly. 相似文献
11.
K. V. Arjuna Gowda M. K. Kokila Puttaraja M. V. Kulkarni N. C. Shivaprakash 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e481-e482
The title molecule, C13H9ClFN, is substantially planar. The phenyl and 3‐chloro‐4‐fluorophenyl rings are on opposite sides of the C=N bond. There is an intermolecular C—H?F short contact with a C?F distance of 3.348 (2) Å and a C—H?F angle of 137.4 (1)°. The molecules are held in layers parallel to the bc plane. 相似文献
12.
Andrew Hempel Lilian Y. Y. Ma Arthur Camerman Donald Mastropaolo Norman Camerman 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o681-o682
In the crystal structure of the title dopaminergic compound, C16H24NO2+·Br−·H2O, protonation occurs at the piperidine N atom. The piperidine ring adopts a chair conformation and the cyclohexene ring adopts a half‐chair conformation; together with the planar benzene ring, this results in a relatively planar shape for the whole molecule. Classical hydrogen bonds (N—H⋯Br, O—H⋯Br and O—H⋯O) produce an infinite three‐dimensional network. Hydrogen bonds between water molecules and Br− anions create centrosymmetric rings throughout the crystal structure. Structural comparison of the molecule with the ergoline dopamine agonist pergolide shows that it is the hydrogen‐bond‐forming hydroxy or imino group that is necessary for dopaminergic activity, rather than the presence of a phenyl or a pyrrole ring per se. 相似文献
13.
Markos M. Papadakis Jorge A. Pavon Roger A. Lalancette Hugh W. Thompson 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o167-o170
The two δ‐keto carboxylic acids of the title, both C10H14O3, are epimeric at the site of carboxyl attachment. The endo (3α) epimer, (I), has its keto‐acid ring in a boat conformation, with the tilt of the carboxyl group creating conformational chirality. The molecules form hydrogen bonds by centrosymmetric pairing of carboxyl groups across the corners of the chosen cell [O⃛O = 2.671 (2) Å and O—H⃛O = 179 (2)°]. Two close intermolecular C—H⃛O contacts exist for the ketone. The exo (3β) epimer exists in the closed ring–chain tautomeric form as the lactol, 8‐hydroxy‐9‐oxatricyclo[5.3.1.03,8]undecan‐10‐one, (II). The molecules have conformational chirality, and the hydrogen‐bonding scheme involves intermolecular hydroxyl‐to‐carbonyl chains of molecules screw‐related in b [O⃛O = 2.741 (2) Å and O—H⃛O = 177 (2)°]. 相似文献
14.
S. M. Malathy Sony M. Kuppayee M. N. Ponnuswamy D. Bhasker Reddy V. Padmavathi Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o678-o680
Due to steric repulsions, the cyclohexane ring in the title compound, C23H24N2O5·H2O, shows some bond‐length abnormalities and adopts a chair conformation. The pyrimidine and cyclohexane rings are approximately perpendicular to each other, and the phenyl rings are equatorial. C—H?π and N—H?O intermolecular interactions, as well as C—H?O inter‐ and intramolecular interactions, occur between the molecules. In addition to van der Waals interactions, the water molecule interacts with the pyrimidinetrione ring to stabilize the structure. 相似文献
15.
Ufuk oruh Bahittin Kahveci Selami amaz Erbil AgÜar Youngme Kim Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):o476-o478
The title compound, C13H13ClN4O2, contains both a phenyl and a triazole ring, both of which are approximately coplanar with the entire molecule. The triazole ring has substituents at the 1‐, 2‐ and 4‐positions. Intramolecular C—H⃛O and C—H⃛N interactions, together with intermolecular C—H⃛O and C—H⃛π interactions, help to stabilize the structure. 相似文献
16.
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
17.
Cecilia Rodríguez de Barbarín Sylvain Berns Francisco Snchez‐Viesca Martha Berros 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o360-o362
In the structure of the title compound, C10H8BrNS, the dihedral angles between the planes of the thiazole and aryl rings, viz. 4.2 (6) and 7.5 (6)° for the two independent molecules, are consistent with insignificant molecular perturbation by the weak intermolecular contacts. The molecules are close to being related by a non‐crystallographic inversion centre, with C—H⃛π and π–π intermolecular interactions observed. 相似文献
18.
Antonio Quesada Manuel Melguizo John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o400-o402
The title compound, C18H17N3O2, crystallizes with Z′ = 2 in space group P21/c, and the two independent molecules are approximate, but not exact, mirror images. The molecular–electronic structure is strongly polarized, and the molecules are linked by paired N—H⃛O hydrogen bonds [H⃛O = 2.00–2.23 Å, N⃛O = 2.798 (3)–2.992 (3) Å and N—H⃛O = 145–151°] into two independent C(4)C(6)[(6)] chains of rings, which are linked into sheets by a single aromatic π–π‐stacking interaction. 相似文献
19.
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
20.
Vratislav Langer Miroslav Ko Dalma Gyepesov Juraj Kronek Jozef Lusto Mariana Sldkovi
ov 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(10):o602-o606
Crystal structures are reported for three isomeric compounds, namely 2‐(2‐hydroxyphenyl)‐2‐oxazoline, (I), 2‐(3‐hydroxyphenyl)‐2‐oxazoline, (II), and 2‐(4‐hydroxyphenyl)‐2‐oxazoline, (III), all C9H9NO2 [systematic names: 2‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (I), 3‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (II), and 4‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (III)]. In these compounds, the deviation from coplanarity of the oxazoline and benzene rings is dependent on the position of the hydroxy group on the benzene ring. The coplanar arrangement in (I) is stabilized by a strong intramolecular O—H⋯N hydrogen bond. Surprisingly, the 2‐oxazoline ring in molecule B of (II) adopts a 3T4 (C2TC3) conformation, while the 2‐oxazoline ring in molecule A, as well as that in (I) and (III), is nearly planar, as expected. Tetramers of molecules of (II) are formed and they are bound together via weak C—H⋯N hydrogen bonds. In (III), strong intermolecular O—H⋯N hydrogen bonds and weak intramolecular C—H⋯O hydrogen bonds lead to the formation of an infinite chain of molecules perpendicular to the b direction. This paper also reports a theoretical investigation of hydrogen bonds, based on density functional theory (DFT) employing periodic boundary conditions. 相似文献