共查询到20条相似文献,搜索用时 15 毫秒
1.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):e64-e65
The crystal structure of the title compound, C8H16N2O3S·2C3H8O, is divided into hydrophobic and hydrophilic layers. Two peptide molecules in the asymmetric unit are related by pseudo‐translational symmetry along the a axis, as are two of the four 2‐propanol molecules. The last two 2‐propanol molecules in the asymmetric unit have different relative orientations and hydrogen‐bond interactions. 相似文献
2.
Mark Davison Elizabeth M. Kikolski Roger A. Lalancette Hugh W. Thompson 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o449-o451
In the title compound, C10H16O3, the two molecules of the asymmetric unit form acid‐to‐ketone hydrogen‐bonded chains. The two species differ only very slightly and are related by a pseudo‐center, so that the apparent translational relationship among the units of the hydrogen‐bonded chain is actually a pseudo‐translation, with the molecules alternating in type. Two counterdirectional pairs of chains proceed through each cell [O⋯O = 2.743 (2) and 2.683 (2) Å, and O—H⋯O = 171 (3) and 157 (3)°]. Three intermolecular C—H⋯O close contacts were found, involving all three O atoms of one of the molecules. 相似文献
3.
Alan Hazell Christine J. McKenzie Jimmi Nielsen 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):859-860
The title compound, C9H9NS3, crystallizes with two molecules in the asymmetric unit. In both molecules, the dithiane‐2‐thione rings adopt a symmetric half‐boat conformation with the C atom opposite the C—Sthione bond out of the plane. The pyridine ring is in an equatorial position and is twisted out of the plane of the half‐boat by 82.7 (2) and 84.5 (2)° in the two molecules, so that the N atom is trans to the axial C—H bond in both cases. 相似文献
4.
Brian T. Holmes Clifford W. Padgett William T. Pennington 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o114-o116
The title compound, C34H26N4·2CH2Cl2, lies about an inversion center. The solvent molecules interact with the benzene molecule both through C—H⃛N hydrogen bonding to span pyridine N atoms of adjacent vinyl groups, possibly stabilizing the rotational conformation observed, and through a π interaction between a dichloromethane Cl atom and a pyridyl ring C—C bond of a c‐glide‐related molecule. The benzene molecules form stacks along the a axis such that two of the four olefin groups are properly oriented for photoreactivity (2+2 cyclodimerization). 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.
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
7.
Damon A. Parrish A. Alan Pinkerton 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):o80-o82
The title solvate of the steroid 17β‐estradiol (E2) with methanol and water, C18H24O2·0.67CH4O·0.33H2O, is the first E2 derivative to contain three crystallographically independent molecules in the asymmetric unit. The three steroid molecules, along with two methanol molecules and a water molecule, create a three‐dimensional hydrogen‐bonded system. Three‐sided columns are formed, with the estradiol molecules aligned lengthwise parallel to (101), and joined by solvent molecules at both hydrophilic ends. The three estradiol molecules differ slightly in their ring‐bowing angles, i.e. the angle between the mean plane of the A ring and that of the BCD ring; this angle ranges from 7.1 to 12.2°. 相似文献
8.
John Nicolson Low Justo Cobo Manuel Nogueras Adolfo Snchez Braulio Insuasty Harlen Torres 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o39-o41
2,2‐Dimethyl‐5‐[3‐(4‐methylphenyl)‐2‐propenylidene]‐1,3‐dioxane‐4,6‐dione, C16H16O4, crystallizes in the triclinic space group , with two molecules in the asymmetric unit. These molecules and a centrosymmetrically related pair, linked together by weak C—H?O hydrogen bonds, form a tetramer. 5‐[3‐(4‐Chlorophenyl)‐2‐propenylidene]‐2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione, C15H13ClO4, also crystallizes in the triclinic space group , with one molecule in the asymmetric unit. Centrosymmetrically related molecules are linked together by weak C—H?O hydrogen bonds to form dimers which are further linked by yet another pair of centrosymmetrically related C—H?O hydrogen bonds to form a tube which runs parallel to the a axis. 相似文献
9.
Jun‐Gill Kang Jung‐Pyo Hong Il‐Hwan Suh 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):231-232
In the crystal structure of the title compound, 4‐cyano‐N‐(4‐methoxybenzylidene)phenylamine N‐oxide, C15H12N2O2, the 4‐methoxyphenyl is approximately coplanar with the nitrone moiety but significantly rotated with respect to the 4‐cyanophenyl moiety. The extent of this rotation is significantly different for the two crystallographically independent molecules of the asymmetric unit [dihedral angles of 19.4 (1) and 26.5 (1)°]. The geometry about the C=N bond is Z. The two molecules are related to one another by a pseudo inversion centre. 相似文献
10.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):o660-o661
The crystal structure of the title compound, C15H17NO2, contains two nearly identical but crystallographically independent molecules, each with a double bond connecting an azabicyclic ring system to a 3‐methoxybenzylidene moiety. The space group is triclinic P. The benzene ring is twisted by 18.44 (5) and 22.35 (4)° with respect to the plane of the double bond connected to the azabicyclic ring system for the two molecules. In addition to C—H⋯π interactions, molecules are held together in the solid state by van der Waals interactions. 相似文献
11.
Miroslav Bo
a Duan Valigura Ingrid Svoboda Hartmut Fuess Wolfgang Linert 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):838-839
The title compound, C19H14N5+·ClO4?·H2O, contains planar C19H14N5+ cations, perchlorate anions and water molecules. The two closest parallel cations (plane‐to‐plane distance of 3.41 Å), together with two neighbouring perchlorate anions and two water molecules, form an electrically neutral quasi‐dimeric unit. Two acidic H atoms of the cation, both H atoms of the water molecule, the N atoms of the imidazole rings and three of the four O atoms of the perchlorate anion are involved in the hydrogen‐bonding network within the dimeric unit. The remaining third acidic H atom of the imidazole rings and the water molecules complete a two‐dimensional network of hydrogen bonds, thus forming puckered layers of dimers. The angle between the planes of two neighbouring dimeric units in the same layer is 33.25 (3)°. 相似文献
12.
Abdurrahman engül Nevzat Karaday 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(8):o539-o541
The title compound, C27H27N5O3·H2O, is built up from pyrazolinone, phenyl and acetophenone oxime moieties. The 2‐phenyl substituent is nearly perpendicular to the pyrazolinone ring, with a dihedral angle of 87.66 (1)°. The acetophenone oxime moieties are twisted out of the pyrazolinone‐ring plane by 47.04 (1)°. The molecules in the crystal pack in an antiparallel fashion and are held together by hydrogen‐bonded water molecules and intermolecular O—H⋯O and O—H⋯N hydrogen bonds. 相似文献
13.
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
14.
Ernesto Castro Luis E. Cuca Suarez Peter Siengalewicz Rene Gutmann Georg Czermak Peter Brueggeller 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o467-o469
The structure of the title compound, C23H32O4, an arylalkanone isolated from the petroleum ether fraction of the ethanol extract of the bark of Virola venosa, has been established by NMR spectroscopy and, for the first time, by X‐ray structure analysis. Two independent molecules of the same enantiomer are present in the unit cell. Both molecules exhibit an intramolecular hydrogen bond, which can be correlated with a rare signal observed at 18.28 p.p.m. in the 1H NMR spectrum. The packing, in space group P1, is determined by a pseudo‐center of symmetry leading to a short intermolecular contact, which is present in one molecule but does not occur in the other. As a consequence, the O—C—C—O torsion angles [−16.9 (3) and −12.7 (3)°] through the ketone and its adjacent hydroxy group are significantly different in the two molecules. 相似文献
15.
Sergiy V. Rosokha Jian Jiang Lu Sergey M. Dibrov Jay K. Kochi 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o464-o466
The title compound, C6H2N6O10·2C2H4Cl2, forms layered stacks of pentanitroaniline molecules, which possess twofold symmetry. The voids between these stacks are occupied by dichloroethane molecules, which reside near a 2/m symmetry element and display pseudo‐inversion symmetry. The C atoms in one of the two solvent molecules are threefold disordered. In the pentanitroaniline molecule, considerable distortion of the benzenoid ring, coupled with the short C—N(H2) bond and out‐of‐plane NO2 twistings, point to significant intramolecular `push–pull' charge transfer at the amino‐ and nitro‐substituted (ortho and para) positions, as theoretically quantified by natural bond orbital analysis of the π‐electron density. 相似文献
16.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o328-o330
The title compound, C20H21N3O3·0.75H2O, crystallizes as exceedingly thin fibers. The crystal packing arrangement is related to those of other hydrophobic dipeptides with phenylalanine residues, but the structure has pseudo‐tetragonal symmetry in an orthorhombic space group with four peptide molecules and three water molecules in the asymmetric unit. 相似文献
17.
Daniel Vega Daniel Fernndez Gustavo Echeverría 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1009-1010
The crystal structure of racemic Venlafaxine hydrochloride, C17H28NO2+·Cl?, consists of two types of parallel chains formed by translated Venlafaxine+ cations, hydrogen bonded by Cl? anions, and characterized by the opposite chirality of their constituent molecules. These chains organize in two different types of broad layers of opposite handedness, related by a glide plane. 相似文献
18.
Vladimir N. Nesterov David J. Wiedenfeld Svitlana V. Nesterova Lucas F. Hastings 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):o705-o708
The syntheses, X‐ray structural investigations and calculations of the conformational preferences of the carbonyl substituent with respect to the pyran ring have been carried out for the two title compounds, viz. C15H14N2O2, (II), and C20H16N2O2·C2H3N, (III), respectively. In both molecules, the heterocyclic ring adopts a flattened boat conformation. In (II), the carbonyl group and a double bond of the heterocyclic ring are syn, but in (III) they are anti. The carbonyl group forms a short contact with a methyl group H atom in (II). The dihedral angles between the pseudo‐axial phenyl substituent and the flat part of the pyran ring are 92.7 (1) and 93.2 (1)° in (II) and (III), respectively. In the crystal structure of (II), intermolecular N—H⋯N and N—H⋯O hydrogen bonds link the molecules into a sheet along the (103) plane, while in (III), they link the molecules into ribbons along the a axis. 相似文献
19.
20.
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