共查询到20条相似文献,搜索用时 31 毫秒
1.
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
2.
Xiu‐Li You Cheng‐Rong Lu Yong Zhang De‐Chun Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o693-o695
Molecular packing analyses were carried out on 15 crystal data sets of chloro‐substituted Schiff bases, including that of the title compound, C15H15ClN2. C—H⋯π and π–π interactions play a major role in the molecular self‐assembly in the crystal. The former interactions favor molecules assembling into a screw, with a non‐centrosymmetric crystal structure. When the molecular dipole is small, π–π interactions favor a parallel, but not usually antiparallel, mode of packing. Weak C—H⋯X hydrogen bonds (X = Cl or Br) and X⋯X interactions seem to be a secondary driving force in packing. The title molecule takes the trans form and the two benzene rings are twisted around the central linkage in opposite directions. In the crystal structure, molecules interact through C—H⋯π and π–π interactions, forming a `dimer' and further forming double chains along [001]. The double chains are extended along [10] through C—H⋯Cl hydrogen bonds, forming double layers in (010). In the third direction, there are only ordinary, weaker, van der Waals interactions, which explains the crystal habit (i.e. thin plate). 相似文献
3.
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
4.
T. Vijay T. Narasimhamurthy H. S. Yathirajan R. S. Rathore P. Nagaraja 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(1):o36-o38
In the crystal structure of the title salt, C7H7Cl2N2O2+·Cl−, the chloride anions participate in extensive hydrogen bonding with the aminium cations and indirectly link the molecules through multiple N+—H⋯Cl− salt bridges. There are two independent molecules in the asymmetric unit, related by a pseudo‐inversion center. The direct intermolecular coupling is established by C—H⋯O, C—H⋯Cl and C—Cl⋯Cl− interactions. A rare three‐center (donor bifurcated) C—H⋯(O,O) hydrogen bond is observed between the methylene and nitro groups, with a side‐on intramolecular component of closed‐ring type and a head‐on intermolecular component. 相似文献
5.
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
6.
Bernard Marciniak 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o252-o254
The asymmetric unit of the title compound, C10H8O2, contains two planar symmetry‐independent molecules linked by an O—H⋯O hydrogen bond. In the crystal structure, molecules are linked into infinite chains of rings, formed by a combination of O—H⋯O and C—H⋯O hydrogen bonds, and additionally reinforced by π–π stacking interactions. Adjacent chains are connected by weak C—H⋯π interactions. 相似文献
7.
Kamlakar Avasthi Chandralata Bal Ashoke Sharon Prakas R. Maulik 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(9):o494-o495
The molecular structure of the title compound, C17H20N4OS2, does not show any intramolecular aromatic π–π interactions, but the crystal packing reveals the presence of intermolecular C—H...O and C—H...π interactions. The C—H...O interactions generate chains of molecules that are linked into sheets by C—H...π interactions about inversion centres. 相似文献
8.
Marijana Juki Mario Cetina Jasna Vorkapi‐Fura
Amalija Golobi
Ante Nagl 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o357-o359
Crystal structure analysis of the title compound, C13H12ClNO, reveals three crystallographically independent molecules in the asymmetric unit. The main conformational difference between these molecules is the orientation of the phenyl rings with respect to the pyrrole rings. The coplanar arrangement of the aldehyde groups attached to the pyrrole rings influences the pyrrole‐ring geometry. The C2—C3 and N1—C5 bonds are noticeably longer than the C4—C5 and N1—C2 bonds. Two independent molecules of the title compound form dimers via intermolecular C—H⃛O hydrogen bonds [D⃛A = 3.400 (3) Å and D—H⃛A = 157°]. The perpendicular orientation of the phenyl and pyrrole rings of one independent molecule and its symmetry‐related molecule allows C—H⃛π interactions, with an H⃛centroid distance of 2.85 Å and a C—H⃛π angle of 155°. The distances between the H atom and the pyrrole‐ring atoms indicate that the C—H bond points towards one of the bonds in the pyrrole ring. 相似文献
9.
Lidia Armelao Giovanni Depaoli Alessandro Dolmella 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e268-e268
In the crystal of the title compound, C10H12O2, there are two symmetry‐independent molecules, which are essentially superimposable. Each molecule exhibits an intramolecular O—H?O hydrogen bond, with O?O separations of 2.483 (4) and 2.468 (4) Å. 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.
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
12.
Md. Abdul Jabbar Isao Aritome Hisashi Shimakoshi Yoshio Hisaeda 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o663-o665
The title compound, C14H10Cl2, crystallizes as colourless prisms with two symmetry‐independent molecules in the unit cell. Numerous intermolecular C—H⋯π interactions dominate in the crystal structure, where C—H⋯Cl and long Cl⋯Cl contacts are also observed. 相似文献
13.
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
14.
Marc A. Grundl Jan W. Bats A. Stephen K. Hashmi 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):653-656
The crystal structure of the title compound, C26H34O4, shows a reversible phase transition at about 178 K. The structure of the high‐temperature phase contains two independent molecules related by pseudosymmetry elements. Cooling through the phase‐transition temperature results in a doubling of the c axis. The low‐temperature structure contains four independent molecules related by pseudosymmetry elements. The phase transition results in a rearrangement of some weak intermolecular C—H?O interactions. The number of very weak C—H?O interactions, with H?O distances between 2.8 and 2.9 Å, is increased in the low‐temperature structure. 相似文献
15.
Urmila H. Patel Chaitanya G. Dave Mukesh M. Jotani Hetal C. Shah 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):o697-o699
The title compound, C20H16N2O, has two molecules in the asymmetric unit and the crystal structure shows that the central pyridine ring of each molecule has a flat boat conformation. The terminal C atom in one of the molecules is disordered over two positions, with relative occupancies of 0.594 (14) and 0.398 (14). Intermolecular C—H?N and C—H?π interactions and π–π stacking, along with intramolecular C—H?N and C—H?π interactions, help to stabilize the structure. 相似文献
16.
Jacek Zaleski Grzegorz Spaleniak Janusz B. Kyzio 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o627-o629
The geometries of the thiazole ring and the nitramino groups in N‐(3H‐thiazol‐2‐ylidene)nitramine, C3H3N3O2S, (I), and N‐methyl‐N‐(thiazol‐2‐yl)nitramine, C4H5N3O2S, (II), are very similar. The nitramine group in (II) is planar and twisted along the C—N bond with respect to the thiazole ring. In both structures, the asymmetric unit includes two practically equal molecules. In (I), the molecules are arranged in layers connected to each other by N—H⋯N and much weaker C—H⋯O hydrogen bonds. In the crystal structure of (II), the molecules are arranged in layers bound to each other by both weak C—H⋯O hydrogen bonds and S⋯O dipolar interactions. 相似文献
17.
Christopher Glidewell John N. Low Manuel Melguizo Antonio Quesada 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(1):o14-o18
In 2‐amino‐4,6‐dimethoxy‐5‐nitropyrimidine, C6H8N4O4, the molecules are linked by one N—H⋯N and one N—H⋯O hydrogen bond to form sheets built from alternating R(8) and R(32) rings. In isomeric 4‐amino‐2,6‐dimethoxy‐5‐nitropyrimidine, C6H8N4O4, which crystallizes with Z′ = 2 in P, the two independent molecules are linked into a dimer by two independent N—H⋯N hydrogen bonds. These dimers are linked into sheets by a combination of two‐centre C—H⋯O and three‐centre C—H⋯(O)2 hydrogen bonds, and the sheets are further linked by two independent aromatic π–π‐stacking interactions to form a three‐dimensional structure. 相似文献
18.
Suchada Chantrapromma Anwar Usman Hoong‐Kun Fun Bo‐Long Poh Chatchanok Karalai 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o675-o677
In the title adduct, 1,3,5,7‐tetraazatricyclo[3.3.1.13,7]decane–4‐nitrobenzene‐1,2‐diol–water (1/2/1), C6H12N4·2C6H5NO4·H2O, the hexamethylenetetramine molecule acts as an acceptor of intermolecular O—H?N hydrogen‐bonding interactions from the water molecule and the hydroxy groups of one of the two symmetry‐independent 4‐nitrocatechol molecules. The structure is built from molecular layers which are stabilized by three intermolecular O—H?O, two intermolecular O—H?N and four intermolecular C—H?O hydrogen bonds. The layers are further interconnected by one additional intermolecular O—H?N and two intermolecular C—H?O hydrogen bonds. 相似文献
19.
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
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