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1.
Shaune McFarlane Robert McDonald Jonathan G. C. Veinot 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o671-o673
The title compound, C29H42, crystallizes from the melt as a triclinic crystal. The unit cell contains three crystallographically independent molecules. The three fluorene ring systems are oriented such that two non‐equivalent ring systems related by a roto‐translation are separated by a third ring system oriented orthogonally to them. The octyl chains of all three molecules are perpendicular to the fluorene ring system and force a 7.4 Å separation between the two coplanar molecules, thereby preventing molecular π‐stacking. 相似文献
2.
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
3.
S. Thamotharan V. Parthasarathi Ranju Gupta D. P. Jindal Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o405-o407
The asymmetric unit of the title compound, C25H30FN3O·0.5CH3OH, contains four symmetry‐independent steroid and two methanol molecules. The conformations of the independent steroid molecules are very similar. Intermolecular O—H⋯O hydrogen bonds create two independent chains, each of which links two of the independent steroid molecules plus one methanol molecule via a co‐operative O—H⋯O—H⋯O—H pattern. Intermolecular C—H⋯O and C—H⋯F interactions are also observed. 相似文献
4.
eljko K. Jaimovi Zoran D. Tomi Gerald Giester Vukadin M. Leovac 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):m381-m383
In the crystal structure of the title complex, [Co(C6H8N3S)3], the CoIII atom is octahedrally coordinated by three monodeprotonated bidentate 3,5‐dimethyl‐1H‐pyrazole‐1‐thiocarboxamide ligands with two thiocarboxamide N atoms in axial positions. The asymmetric unit contains two molecules (A and B) and these molecules are arranged in chains in an alternating fashion connected by N—H⋯S interactions. 相似文献
5.
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
6.
Ahmet Karadag Ahmet Bulut Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(8):m402-m404
The crystal structure of the title compound, [Ni(NCS)2(C4H12N2O)2], has two crystallographically independent half‐molecules in the asymmetric unit, with each Ni atom residing on a centre of symmetry. The two molecules exhibit similar coordination geometry but display differences with regard to other structural features. Each NiII centre is octahedrally coordinated by two mutually trans chelating hydroxyethylethylenediamine ligands and two mutually trans isothiocyanate ions. The two independent molecules form chains through different types of non‐covalent interactions. In the case of one of the molecules, only NCS and free OH groups participate in hydrogen bonding, while in the chain based on the second molecule, the NCS, NH, NH2 and free OH groups are involved in intermolecular hydrogen bonding. The two chains interact with one another through hydrogen bonding, forming planar sheets. The third packing direction is mediated only by van der Waals interactions. 相似文献
7.
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
8.
Yu‐Xi Sun Ran Zhang Qing‐Mai Jin Xi‐Jing Zhi Xiao‐Ming Lü 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o467-o469
The two title compounds, both with formula C18H16ClN3O, are structurally similar Schiff bases derived from the condensation of 4‐chlorobenzaldehyde or 2‐chlorobenzaldehyde with 4‐aminoantipyrine in methanol solution. As expected, both compounds adopt trans configurations about the central C=N bonds. In the crystal structure of the 4‐chloro analogue, molecules are linked through weak C—H⋯O hydrogen bonds, forming chains running along the a axis. In the crystal structure of the 2‐chloro analogue, molecules are linked through weak C—H⋯O and C—H⋯Cl hydrogen bonds, forming layers parallel to the ab plane. 相似文献
9.
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
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.
Alexander B. Zolotoy Mark Botoshansky Menahem Kaftory 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o148-o150
The title compound, C9H12N2O, crystallizes in a triclinic unit cell, with two crystallographically independent molecules in the asymmetric unit. The two independent molecules adopt different modes of packing. One type of molecule is arranged in infinite columns, while the other type packs as dimers, forming spacers between the parallel columns. Each type of molecule is arranged in pairs related by inversion centers. The distances between potential reaction centers are 3.395 (2), 3.457 (2) and 3.522 (2) Å. As a result of the symmetry of the pairs and the close distances between the potential photoreactive centers, it is expected that the dimer will be the anti–trans isomer. 相似文献
12.
Uwe Hamann Jan Kmpen Peter Bubenitschek Henning Hopf Peter G. Jones 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o178-o181
The title 1,2‐diol derivative, C10H12O2, crystallizes with two independent but closely similar molecules in the asymmetric unit. Only two of the four OH groups are involved in classical hydrogen bonding; the molecules thereby associate to form chains parallel to the short c axis. The other two OH groups are involved in O—H⋯(C[triple‐bond]C) systems. Additionally, three of the four C[triple‐bond]C—H groups act as donors in C—H⋯O interactions. The 1,4‐diol derivative crystallizes with two independent half‐molecules of the diol (each associated with an inversion centre) and one water molecule in the asymmetric unit, C12H16O2·H2O. Both OH groups and one water H atom act as classical hydrogen‐bond donors, leading to layers parallel to the ac plane. The second water H atom is involved in a three‐centre contact to two C[triple‐bond]C bonds. One acetylenic H atom makes a very short `weak' hydrogen bond to a hydroxy O atom, and the other is part of a three‐centre system in which the acceptors are a hydroxy O atom and a C[triple‐bond]C bond. 相似文献
13.
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
14.
Peter G. Jones Joaquín Lpez‐Serrano 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):m16-m18
The title compound, [Pd(C19H17NO4)I(C18H15P)], crystallizes with four independent molecules in the asymmetric unit. The main difference between the molecules is the disposition of the PPh3 ligand, for which in each molecule one ring is perpendicular to the ligand plane, but may be directed in either direction away from the plane; of the four molecules, two represent each possible direction. The independent molecules are arranged to form a chain parallel to [101] with an approximate translation of (a+c)/4 between successive molecules, excluding the PPh3 rings. This leads to a systematic weakness of the reflections with h + l≠ 4n. 相似文献
15.
Swastik Mondal Monika Mukherjee Arnab Roy Debabrata Mukherjee Madeleine Helliwell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o474-o476
In the title compound, C13H22O3, the asymmetric unit has two independent molecules linked by a strong O—H?O hydrogen bond. The cyclohexane ring is trans fused to the cyclopentane ring bridged through an ethyl moiety. The hydroxyl groups act as donors as well as acceptors, resulting in an extensive two‐dimensional hydrogen‐bonded network in the (011) plane. Intermolecular O—H?O bonds between centrosymmetrically related molecules form a four‐membered supramolecular assembly, leading to infinite chains parallel to the [01] direction, crosslinked in the [100] direction. 相似文献
16.
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
17.
Franois Loiseau Reinhard Neier Gaël Labat Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o636-o638
In the title compound, C9H12Br2O3, a (tetrahydrofuran‐2‐ylidene)acetate, the double bond has the Z form. In the tetrahydrofuran group, the relative configuration of the Br atom in the 3‐position and the methyl group in the 5‐position is anti. The compound crystallizes with two independent molecules per asymmetric unit and, in the crystal structure, the individual molecules are linked to their symmetry‐equivalent molecules by C—H⋯O hydrogen bonds, so forming centrosymmetric hydrogen‐bonded dimers. 相似文献
18.
Vratislav Langer Dalma Gyepesov Pavel Mach Eva Scholtzov Marta Saliov Andrej Boh
Boris Gpr 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o199-o202
Crystals of the title racemic compound, C11H13NO2, consist of two types of molecules (conformers); one molecule has an exocyclic OH group in an equatorial position and the other has this group in an axial position. Consequently, the hydrogen‐bond schemes for the two molecules are different. The molecules with equatorial OH groups create infinite parallel chains (formed by the same enantiomer), connected by centrosymmetric dimers of molecules (of mixed enantiomers), both with axial OH groups. Possible interconversion of the conformers and the flexibility of the molecule were studied by means of different MP2 and density functional theory (DFT) methods. The optimization of the structure by the DFT method confirmed the types of the hydrogen bonds. 相似文献
19.
Eleonora Freire Sergio Baggio Juan Carlos Muoz Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):o259-o262
The structures of the mono‐ and sesquihydrates of 2,6‐bis(1H‐benzimidazol‐2‐yl)pyridine (bbip) are reported. Phase (I), C19H13N5·H2O, has one water and one bbip molecule in the asymmetric unit, while phase (II), C19H13N5·1.5H2O, has three water molecules and two bbip molecules in the asymmetric unit. The compounds exhibit very similar molecular geometries but different packing organizations, which result from intricate hydrogen‐bonding schemes. 相似文献
20.
Doyle Britton 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):o35-o37
The title compound, C13H9NO, crystallizes with four molecules in the asymmetric unit. Each of the four crystallographically independent molecules forms a chain parallel to the a axis with symmetry‐equivalent molecules. These chains are held together by similar O—H·NC hydrogen bonds, with approximately linear O—H·N angles and significantly bent H·N—C angles. The four different molecules are related by strong elements of pseudosymmetry. To better describe the pseudosymmetry, the structure has been reported in the non‐standard space group . 相似文献