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1.
Pawe Wagner Mieczysaw apkowski Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o155-o156
Molecules of the title compound, C20H28O4S2, the first compound with a tetraoxacyclohexacosane ring to be structurally characterized, lie on crystallographic centres of inversion, but have approximate C2h molecular symmetry. The parallel thiophene rings are almost exactly planar; the overall conformation of the molecule is chair‐like. The molecules have voids that could, in principle, accommodate small guest molecules, although in the crystal structure access to these voids is blocked by neighbouring molecules. 相似文献
2.
John Nicolson Low Justo Cobo Braulio Insuasty Henry Insuasty Manuel Nogueras Adolfo Snchez 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o103-o105
In both title compounds, i.e. 3‐methyl‐1,5‐diphenyl‐1,6,7,8‐tetrahydropyrazolo[3,4‐b][1,4]diazepine, C19H18N4, (I), and 5‐(4‐chlorophenyl)‐3‐methyl‐1‐phenyl‐1,6,7,8‐tetrahydropyrazolo[3,4‐b][1,4]diazepine, C19H17ClN4, (II), an N—H?N hydrogen bond links six molecules to form an R(30) ring. Compound (I) crystallizes in the R space group and (II) crystallizes in P with three molecules in the asymmetric unit. The molecule of (I) contains a disordered seven‐membered ring. 相似文献
3.
Gopeswar Chaudhuri Madeleine Helliwell Nitya G. Kundu 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):740-741
In the title compound, C22H17Cl2NO3S, the molecule is a substituted 3,4‐dihydro‐2H‐1,4‐benzoxazine compound which has three phenyl rings which are essentially planar. The 3,4‐dihydro‐2H‐oxazine part of the molecule is fused to the benzo ring and has a half‐boat conformation; the dihedral angle between the planar part of the oxazine ring and the benzo ring is 10.2 (2)°. The (3‐chlorophenyl)methylidene substituent has a Z configuration in relation to the ring N atom of the oxazine moiety. Interestingly, the p‐toluenesulfonyl (p‐tosyl) substituent on the ring N atom protrudes away from the 3‐chlorophenyl substituent thus avoiding any steric interaction. 相似文献
4.
Cara Nygren Tianniu Chen Sanbao Zhong Conrad Kaczmarek John F. C. Turner David C. Baker 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o208-o210
The structures of two compounds which are intermediates in the synthesis of phenanthroindolizidine alkaloids have been determined. (8bS,13aS,14R,14aR)‐8b,9,11,12,13,13a,14,14a‐Octahydro‐14‐hydroxy‐2,3,6,7‐tetramethoxydibenzo[f,h]pyrrolo[1,2‐b]isoquinolin‐11‐one acetone solvate, C24H27NO6·C3H6O, (II), crystallizes in a chiral space group with one solvent molecule (acetone) present in the asymmetric unit. On the other hand, (8bS,13aS,14S,14aR)‐8b,9,11,12,13,13a,14,14a‐octahydro‐14‐hydroxy‐2,3,6,7‐tetramethoxydibenzo[f,h]pyrrolo[1,2‐b]isoquinolin‐11‐one, C24H27NO6, (III), crystallizes in a centrosymmetric space group with two molecules in the asymmetric unit and with no solvent present. The two molecules in the asymmetric unit of (III) are structurally the same. Compounds (II) and (III) are epimers at the C atom carrying the OH group; otherwise they are very similar in structure. 相似文献
5.
Lamine Hamdellou Olivier Hernandez Jean Meinnel 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o557-o560
The structures of 4‐dimethylamino‐β‐nitrostyrene (DANS), C10H12N2O2, and 4‐dimethylamino‐β‐ethyl‐β‐nitrostyrene (DAENS), C12H16N2O2, have been solved at T = 100 K. The structure solution for DANS was complicated by the presence of a static disorder, characterized by a misorientation of 17% of the molecules. The molecule of DANS is almost planar, indicating significant conjugation, with a push–pull effect through the styrene skeleton extending up to the terminal substituents and enhancing the dipole moment. As a consequence of this conjugation, the hexagonal ring displays a quinoidal character; the lengths of the C—N [1.3595 (15) Å] and C—C [1.448 (2) Å] bonds adjacent to the benzene ring are shorter than single bonds. The molecules are stacked in dimers with antiparallel dipoles. In contrast, the molecule of DAENS is not planar. The ethyl substituent pushes the nitropropene group out of the benzene plane, with a torsion angle of −21.9 (3). Nevertheless, the molecule remains conjugated, with a shortening of the same bonds as in DANS. 相似文献
6.
Anthony Linden Fatemeh Ghorbani‐Salman Pour Roland A. Breitenmoser Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):634-637
The morpholine ring of the title dione, C13H15NO3, shows a boat conformation that is distorted towards a twist‐boat, with the boat ends being the two Csp3 atoms of the ring. The benzyl substituent is in the favoured `exo' position. In the monothione derivative, (±)‐6‐benzyl‐3,3‐dimethyl‐5‐thioxomorpholin‐2‐one, C13H15NO2S, this ring has a much flatter conformation that is midway between a boat and an envelope, with the dimethyl end being almost planar. The orientation of the benzyl group is `endo'. The dithione derivative, (±)‐6‐benzyl‐3,3‐dimethylmorpholine‐2,5‐dithione, C13H15NOS2, has two symmetry‐independent molecules, which show different puckering of the morpholine ring. One molecule has a flattened envelope conformation distorted towards a screw‐boat, while the conformation in the other molecule is similar to that in the monothione derivative. Intermolecular hydrogen bonds link the molecules in the three compounds, respectively, into centrosymmetric dimers, infinite chains, and dimers made up of one of each of the symmetry‐independent molecules. 相似文献
7.
Eric Gagnon Kenneth E. Maly Thierry Maris James D. Wuest 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):o4-o6
The title compound (systematic name: benzene‐4,4′,4′′,4′′′,4′′′′,4′′′′′‐hexaylhexabenzonitrile dichloromethane disolvate), C48H24N6·2CH2Cl2, crystallizes as an inclusion compound during the slow diffusion of methanol into a solution of hexakis(4‐cyanophenyl)benzene in CH2Cl2. The hexakis(4‐cyanophenyl)benzene molecule lies on an axis of twofold rotation in the space group Pbcn. Weak C—H⋯N interactions between hexakis(4‐cyanophenyl)benzene molecules define an open network with space for including guests. The resulting structure is a new pseudopolymorph of hexakis(4‐cyanophenyl)benzene. The eight known pseudopolymorphs have few shared architectural features, in part because none of the intermolecular interactions that are present plays a dominant role or forces neighboring molecules to assume particular relative orientations. 相似文献
8.
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
9.
Bernardo Masci Stefano Levi Mortera Maurizio Varrone Pierre Thury 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o649-o651
Two compounds containing 1,3‐benzodioxin groups are reported, namely (±)‐6‐tert‐butyl‐8‐hydroxymethyl‐2‐phenyl‐4H‐1,3‐benzodioxin, C19H22O3, (I), and 2,2,2′,2′,6,6′‐hexamethyl‐8,8′‐methylenebis(4H‐1,3‐benzodioxin), C23H28O4, (II).The hydroxy groups of neighbouring molecules in (I) are hydrogen bonded to each other, giving rise to double‐row chains. The molecule in (II) adopts a `butterfly' conformation, with the O atoms in distal positions. In both compounds, the dioxin rings are in distorted half‐chair conformations. 相似文献
10.
Raffaella Soave Riccardo Destro 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o507-o509
The asymmetric unit of the title compound, C22H31N3O4·H2O, incorporates one water molecule, which is hydrogen bonded to the 3‐oxo O atom of the indolizidinone system. The two rings of the peptidomimetic molecule are trans‐fused, with the six‐membered ring having a slightly distorted half‐chair conformation and the five‐membered ring having a perfect envelope conformation. The structure is stabilized by intermolecular O—H?O interactions between the water and adjacent peptide molecules, and by N—H?O interactions between the peptide molecules, which link the molecules into infinite chains. 相似文献
11.
Tali Lavy Yana Sheynin Moshe Kapon Menahem Kaftory 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o50-o53
The crystal structures of three 1:2 inclusion compounds that consist of host molecule 2,5‐diphenylhydroquinone (C18H14O2) and the guest molecules 2‐pyridone (C5H5NO), 1,3‐diphenyl‐2‐propen‐1‐one (chalcone, C15H12O) and 1‐(4‐methoxyphenyl)‐3‐phenyl‐2‐propen‐1‐one (4′‐methoxychalcone, C16H14O2) were determined in order to study the ability of guest molecules in inclusion compounds to undergo photoreaction. All of the crystals were found to be photoresistant. The three inclusion compounds crystallize in triclinic space group . In each case, the host/guest ratio is 1:2, with the host molecules occupying crystallographic centers of symmetry and the guest molecules occupying general positions. The guest molecules in each of the inclusion compounds are linked to the host molecules by hydrogen bonds. In the inclusion compound where the guest molecule is pyridone, the host molecule is disordered so that the hydroxy groups are distributed between two different sites, with occupancies of 0.738 (3) and 0.262 (3). The pyridone molecules form dimers via N—H⋯O hydrogen bonds. 相似文献
12.
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
13.
Vasu K. A. Nirmala A. R. Choudhury S. Mohan J. Saravanan T. Narasimhamurthy 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o676-o678
The two title compounds, 2‐({(1Z)‐[4‐(dimethylamino)phenyl]methylene}amino)‐4,5‐dimethyl‐N‐(2‐methylphenyl)thiophene‐3‐carboxamide, C23H25N3OS, (I), and 2‐({(1E)‐[4‐(dimethylamino)phenyl]methylene}amino)‐N‐(4‐methylphenyl)‐4,5,6,7‐tetrahydro‐1‐benzothiophene‐3‐carboxamide,C25H27N3OS, (II), show antibacterial and antifungal activities. The asymmetric unit of (II) contains two crystallographically independent molecules. The o‐toluidine ring in (I) lies gauche with respect to the thiophene ring. In (II), the p‐toluidine ring is coplanar with the thiophene ring in one molecule, but is tilted from it in the other molecule. Neither structure exhibits any significant intermolecular interactions, but in both, an intramolecular N—H⋯N hydrogen bond forms a pseudo‐six‐membered ring, thus locking the molecular conformation and removing conformational flexibility. 相似文献
14.
Bernardo Masci Martine Nierlich Pierre Thury 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o86-o87
2,3,6,7‐Tetrahydroxy‐9,10‐dimethyl‐9,10‐dihydro‐9,10‐ethanoanthracene crystallizes with 1,4‐dioxane to give a bis‐solvate, C18H18O4·2C4H8O2. The bis(catechol) molecule is located on a twofold axis and the two aromatic rings form a dihedral angle of 130.61 (4)°. Hydrogen bonds are formed between the hydroxyl groups and either a neighbouring bis(catechol) molecule or the ether‐O atom of a dioxane molecule. 相似文献
15.
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
16.
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
17.
Sari M. Kunnari Raija Oilunkaniemi Risto S. Laitinen Markku Ahlgren 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):o610-o611
The novel title tetraselenacalix[4]arene, C16H8S4Se4 or [(C4H2S)Se]4, has a centrosymmetric cyclic molecular structure with approximate C2h molecular symmetry. The four thienyl rings are joined together by Se bridges and exhibit a syn–syn–anti–anti arrangement around the molecule. The lattice consists of skewed stacks of molecules, with chalcogen–chalcogen close contacts binding the stacks together, forming a two‐dimensional network of molecules. 相似文献
18.
Gregori A. Caignan Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(8):934-935
The title compound, C21H27NO6, has been crystallized from ethanol containing nitrobenzene and shows the phenyl ring, B, in an ap conformation. This structure may be compared with that of the molecule crystallized from ethanol alone, in which the B ring is seen in an sp conformation. The isolation of this rotamer has implications for the understanding of the docking of calcium beta‐blocking dihydropyridine molecules with their receptor site. 相似文献
19.
Andrei S. Batsanov Judith A. K. Howard David O'Hagan Mustafa Tavasli 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e567-e568
The title molecule, C12H14OS2, has approximate Cs symmetry. The dithiane ring adopts a chair conformation with the acetyl substituent in an axial orientation. Weak intermolecular C—H?O hydrogen bonds link molecules into a chain along the y axis. 相似文献
20.
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