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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.
G. Y. S. K. Swamy K. Ravikumar B. Sridhar I. Mahender K. V. N. S. Srinivas 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o495-o497
The title compound [systematic name: 5‐hydroxy‐2‐(3‐hydroxy‐4,5‐dimethoxyphenyl)‐3,6,7‐trimethoxy‐4H‐chromen‐4‐one], C20H20O9, was isolated from the seeds of Cleom viscosa Linn. Two independent molecules (A and B) are present in the asymmetric unit with almost similar conformations. The dihedral angles between the fused chromene ring system and the benzene ring bonded to it in molecules A and B are 4.2 (1) and 12.7 (1)°, respectively. The hydroxy O atoms are involved in intramolecular hydrogen bonding. The molecules are linked by C—H⋯O and O—H⋯O interactions into chains of edge‐fused R33(22) rings. Aromatic π–π and weak C—H⋯π(arene) interactions are also observed. 相似文献
3.
G. Mazumder M. De S. K. Mazumder A. Mukhopadhyay A. K. Das A. Van Aerschot 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):560-561
The title compound, 9(R)‐[6(R)‐hydroxymethyl‐1‐oxa‐4‐thiacyclohexan‐2‐yl]‐1,9‐dihydro‐6H‐purin‐6‐one–water (4/3), C10H12N4O3S·0.75H2O, crystallizes in the triclinic space group P1 with four molecules in the asymmetric unit and 0.75 waters of hydration per molecule. The structure was refined to an R value of 0.072 for 3382 observed reflections. The four crystallographically independent molecules are designated A, B, C and D. All four oxathiane rings adopt the chair conformation and the purine bases are in an anti orientation with respect to the sugar moieties. Molecules A and D and molecules C and B are base paired by a single hydrogen bond of the type N—H?N. These base pairs are again hydrogen bonded to their translated pairs in the direction of a cell diagonal. 相似文献
4.
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
5.
M. Yogavel D. Velmurugan W. G. Rajeswaran P. C. Srinivasan H.‐K. Fun 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o715-o717
The title compound, C15H19NO5, crystallizes in the monoclinic space group P21/c with four molecules in the asymmetric unit, which differ from each other in the orientation of their methoxy groups. Of the three methoxy groups in each molecule, one lies close to the plane of the molecule and the other two have an out‐of‐plane conformation where they point in opposite directions. In the crystal structure, four different types of π‐stacks are observed and the molecules pack in two different types of stacking sheets, with alternating molecules A and B in one ribbon and alternating molecules C and D in the other. The supramolecular structure is supported by C—H⋯O and π–π interactions. 相似文献
6.
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
7.
Gilles Gasser Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o514-o516
The title compounds, C22H22N4 and C24H26N4O2 [alternative names: 2,6‐dibenzyl‐2,3,6,7‐tetrahydro‐1H,5H‐dipyrrolo[3,4‐b; 3′,4′‐e]pyrazine and 2,6‐bis(4‐methoxybenzyl)‐2,3,6,7‐tetrahydro‐1H,5H‐dipyrolo[3,4‐b;3′,4′‐e]pyrazine], two 1,2,3,5,6,7‐hexahydro‐2,4,6,8‐tetraaza‐s‐indacene derivatives, are both centrosymmetric and have similar S‐shaped structures. In the former, there are two independent molecules (A and B), both of which possess Ci symmetry. These two molecules are arranged such that the benzene ring substituent of molecule B is directed towards the plane of the benzene ring substituent of molecule A, with a dihedral angle of 55.4 (2)° between their planes. The shortest C—H⋯C distance is, however, only 3.21 (1) Å. In both compounds, the benzene ring substituents are almost perpendicular to the plane of the central pyrazine ring, and the pyrrolidine rings have perfect envelope conformations. In the crystal structures of both compounds, the molecules pack in a herring‐bone arrangement. 相似文献
8.
Guo‐Hai Xu Jian‐Fang Ma Ying‐Ying Liu Shun‐Li Li 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):m581-m583
The title compound, [CrSn(C6H5)3(C7H6NO2)3Cl][Sn(C6H5)3Cl(CH4O)], was obtained from the reaction of Ph3SnCl with the complex [Cr(C7H6NO2)3] in methanol. The structure contains [Ph3SnCl(MeOH)] (A) and [Ph3SnClCr(C7H6NO2)3] (B) molecules. In molecule A, the Sn atom of Ph3SnCl is coordinated by one methanol molecule. In molecule B, the Sn atom of Ph3SnCl is coordinated by one carboxylate O atom of [Cr(C7H6NO2)3]. Molecules A and B are connected through an O—H⋯O hydrogen bond between a carboxylate O atom and the methanol OH group. Weak C—H⋯Cl interactions and O—H⋯O hydrogen bonds extend the components of (I) into a two‐dimensional network. 相似文献
9.
Surajit Banerjee Alok K. Mukherjee Bidisha Nandi Nitya G. Kundu Madeleine Helliwell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1490-1491
The title compound, C20H19NO2S2, is formed by a palladium–copper‐catalyzed reaction between 4‐methyl‐N‐[2‐(prop‐2‐ynylsulfanyl)phenyl]benzenesulfonamide and p‐iodotoluene. The molecules contain three essentially planar parts, namely an aminothiophenol moiety (A), a toluenesulfone moiety excluding the oxo ligands (B) and a tolyl group (C), approximately orthogonal to each other; the dihedral angles A/B, A/C and B/C are 111.6 (1), 89.3 (1) and 101.4 (1)°, respectively. Intermolecular N—H?O hydrogen bonds link the molecules into infinite one‐dimensional chains. 相似文献
10.
Andrea Pretscher Magnus Brisander Annette Bauer-Brandl Lars Kr. Hansen 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1217-1219
In the asymmetric unit of N-(3,5-diamino-6-chloropyrazin-2-ylcarbonyl)-N-(diaminomethylene)ammonium chloride methanol hemisolvate, C6H9ClN7O+·Cl−·0.5CH4O, there are two crystallographically different amiloride molecules. Crystallographically identical amiloride molecules are stacked one above the other, alternately rotated by 180°. These stacks are arranged parallel to each other, forming layer A. The least-squares plane of the non-H atoms of the other molecules lying in layer B is tilted against the corresponding plane of the molecules in layer A by an angle of 79.89 (3)°. The methanol molecules and Cl− anions are located between these layers, although the methanol molecules are closer to layer A. 相似文献
11.
Yu‐Ling Wang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):m522-m524
In the title compound, {[Zn(C10H8N2)(H2O)4](C6H5O4S)2·3H2O}n, the Zn atom, the bipyridine ligand and one of water molecules are located on twofold rotation axes. The Zn atom is coordinated by four O atoms from four water molecules and two N atoms from two 4,4′‐bipyridine molecules in a distorted octahedral geometry. The Zn2+ ions are linked by the 4,4′‐bipyridine molecules to form a one‐dimensional straight chain propagating along the c axis. The 4‐hydroxybenzenesulfonate counter‐ions are bridged by the solvent water molecules through hydrogen bonds to generate a two‐dimensional layer featuring large pores. In the crystal packing, the intralayer pores form one‐dimensional channels along the c axis, in which the one‐dimensional [Zn(C10H8N2)(H2O)4]2+ chains are encapsulated. Electrostatic interactions between cations and anions and extensive hydrogen bonds result in a three‐dimensional supramolecular structure. 相似文献
12.
Goverdhan Mehta Gagliardini Vanessa Kabirul Islam Kailasam Venkatesan 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o90-o93
The cis,syn,cis‐tricyclic [2+2]‐dimer of cyclooctatetraene, C16H16, crystallizes in space group Pca21 with two molecules in the asymmetric unit. An extensive network of weak C—H⋯π(Czdbnd;C) interactions between the two independent molecules, A and B, as well as A⋯A and B⋯B interactions, are observed in the supramolecular assembly. The C—H groups point more towards one C atom than to the centre of the Czdbnd;C bond. Notable among the interactions are bifurcated (cyclobutane)C—H⋯Czdbnd;C contacts that span transannularly the eight‐membered ring. 相似文献
13.
C. Malla Reddy Ashwini Nangia Ram K. R. Jetti Roland Boese 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o331-o333
The crystal structure of the title compound, alternatively called 1,2,3‐triiodo‐5‐(triphenylmethyl)benzene, C25H17I3, is analysed in terms of I⋯I and I⋯π interactions and the herring‐bone T motif between phenyl groups. There are two molecules in the asymmetric unit, denoted A and B. Inversion‐related A molecules are connected via an I⋯π interaction (3.641 Å, to a C—C bond mid‐point) to form an I⋯π dimer, and these dimers are connected through symmetry‐independent B molecules via I⋯I [3.5571 (15) Å] and I⋯π (3.561 Å, to a C—C bond mid‐point) interactions. 相似文献
14.
Daniel Fernndez Daniel Vega Javier A. Ellena 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o187-o189
The title compound, C22H28O5, is a commercial therapeutic agent of the steroid class. Both independent molecules in the asymmetric unit have six‐membered A rings that are planar, while the B and C rings adopt normal chair conformations. The five‐membered D ring is in a 13β,14α‐half‐chair conformation, and the B/C and C/D ring junctions are in trans positions. Cohesion in the crystal is provided by O—H⃛O hydrogen bonds, which generate chains of molecules that are organized in a plane that lies along the crystallographic b axis. 相似文献
15.
Jin‐Nan Zhang Ge Lin Yee‐Ping Ho Ping Li Albert H. L. Chow 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):907-909
The two symmetry‐independent molecules of the title compound, cevane‐3β,6α,20‐triol ethanol hydrate (2/1/1), 2C27H45NO3·C2H6O·H2O, have the same stereochemical assignments. The six‐membered rings A, B, E and F are in the chair conformation, while ring D is in a boat conformation. The ring fusions are A/Btrans, B/Ctrans, C/Dcis, D/Etrans and E/Ftrans. The verticine molecules are bridged by water and ethanol molecules via hydrogen bonds to form two‐dimensional layers, and the crystal structure is built up by stacking of these layers. 相似文献
16.
Peter G. Jones 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):880-882
The crystal structure of the title compound, C5H5NO·H2O, contains five independent molecules of pyridone and six independent water molecules. The space group is P21, but four of the pyridones and four waters correspond closely to P21/n. The packing involves two layers; one consists of head‐to‐tail chains of pyridone molecules 1–4 linked by N—H?O hydrogen bonds, and a second layer involves all the waters and the fifth pyridone. The layers are linked by hydrogen bonds from water to pyridone oxygen. The four water O atoms that accept only one classical hydrogen bond have their environment completed by C—H?O interactions. 相似文献
17.
Ulaganathan Venkatasubramanian David Ellis Georgina M. Rosair Alan J. Welch 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):o559-o561
The title compound, 1,2‐(COOH)2‐1,2‐closo‐C2B10H10·0.5C2H6O or C4H12B10O4·0.5C2H6O, forms a tetramer by incorporating ethanol (solvent) molecules through hydrogen bonding. Two eight‐membered rings [graph set R(8)] are formed by hydrogen bonding between two carboxylic acid groups, whereas two ten‐membered rings [R(10)] are formed by hydrogen bonding between two carboxylic acid groups and the OH group of an ethanol molecule (solvent). Two crystallographically independent tetramers are present in the crystal structure. 相似文献
18.
Simon J. Garden Marilza B. Corrêa Angelo C. Pinto James L. Wardell John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o234-o238
In ethyl N‐[2‐(hydroxyacetyl)phenyl]carbamate, C11H13NO4, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the molecules are linked into simple chains by a single C—H⋯O hydrogen bond. The molecules of ethyl N‐[2‐(hydroxyacetyl)‐4‐iodophenyl]carbamate, C11H12INO4, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐[2‐(hydroxyacetyl)‐4‐methylphenyl]carbamate, C12H15NO4, crystallizes with Z′ = 2 in the space group P; pairs of molecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking interactions. 相似文献
19.
Debbie Cannon Christopher Glidewell John N. Low Antonio Quesada James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(2):216-221
4-Methyl-2-nitroaniline, (I), C7H8N2O2, crystallizes with two molecules in the asymmetric unit. The molecules both form intramolecular N—H⃛O hydrogen bonds and they are linked into hydrogen-bonded C22(12) chains in which the two independent molecules alternate. 4,5-Dimethyl-2-nitroaniline, (II), C8H10N2O2, also has Z′ = 2 and the two independent molecules each form hydrogen-bonded C(6) chains. In 4-methyl-3-nitroaniline, (III), C7H8N2O2, there are four molecules in the asymmetric unit. Molecules of two of these types are linked by N—H⃛O hydrogen bonds into molecular ladders containing R43(18) rings and the other two types independently form single C(7) chains. 相似文献
20.
Zhibin Zhang Eric Burkholder Jon Zubieta 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o452-o454
N,N′‐Bis(3‐methylphenyl)‐N,N′‐diphenyl‐1,1′‐biphenyl‐4,4′‐diamine (TPD), C38H32N2, crystallizes in the monoclinic space group P21 with a pseudo‐orthogonal lattice, rather than the previously reported orthorhombic space group P212121 [Kennedy, Smith, Tackley, David, Shankland, Brown & Teat (2002). J. Mater. Chem. 12 , 168–172]. The asymmetric unit consists of two independent molecules, A and B, which are arranged along the [100] direction to form vertical layers of alternately stacked A and B molecules. Molecule A shows a great deal of rotational movement in the four terminal aryl rings, resulting in two disordered tolyl groups split over two sites, while molecule B exhibits an almost cis configuration of the two terminal tolyl groups with respect to these ring planes. 相似文献