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1.
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
2.
Jing‐Jing Nie Duan‐Jun Xu Zi‐Qiang Hu Yuan‐Zhi Xu Jing‐Yun Wu Michael Y. Chiang 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o106-o107
The title chiral compound, 3‐aminocarbonyl‐1,2,2‐trimethylcyclopentane‐1‐carboxylic acid, C10H17NO3, was prepared from (1R,3S)‐camphoric acid. The five‐membered ring adopts a conformation which is intermediate between a twist and an envelope. Elongations of the C—C bonds and contractions of the C—C—C bond angles are observed within the five‐membered ring. A 1H NMR spectrum was recorded to assist in distinguishing the amide group from the carboxyl group. 相似文献
3.
Kinkini Bhattacharyya Tanusree Kar Rex A. Palmer Brian S. Potter Akira Inada 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):979-980
In the title compound, C30H50O3, the three six‐membered rings adopt chair, twist and twist‐boat conformations. The five‐membered ring is in a slightly distorted envelope conformation. The substituent on the five‐membered ring is in an extended conformation, with its two hydroxyl O atoms forming an intramolecular hydrogen bond. One of these O atoms also forms an intermolecular hydrogen bond with the oxygen of the carbonyl group in a neighbouring molecule. 相似文献
4.
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
5.
Giuseppe Bruno Francesco Nicol Rosaria Gitto Nicola Micale Giuseppe Rosace 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o117-o119
The title compound, C16H12N2O3, is a novel potent and selective non‐competitive antagonist at AMPA/kainate receptors [AMPA is 2‐amino‐3‐(3‐hydroxy‐5‐methylisoxazol‐4‐yl)propionic acid and kainate is 3‐carboxymethyl‐4‐isopropenylpyrrolidine‐2‐carboxylic acid]. The crystal structure has been determined at room temperature by X‐ray diffraction and the seven‐membered ring shows the usual boat conformation. The energy stabilization of the crystal packing of the title compound by significant hydrogen‐bond interactions is discussed using theoretical computations. 相似文献
6.
Alexander V. Pestov Eugenia V. Peresypkina Alexander V. Virovets Nina V. Podberezskaya Yury G. Yatluk Yury A. Skorik 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):m510-m512
The CuII ion in the title complex, [Cu(C5H10NO3)2] or [Cu(He‐ala)2] [He‐ala = N‐(2‐hydroxyethyl)‐β‐alaninate], resides at the inversion centre of a square bipyramid comprised of two facially arranged tridentate He‐ala ligands. Each He‐ala ligand binds to a CuII ion by forming one six‐membered β‐alaninate chelate ring in a twist conformation and one five‐membered ethanolamine ring in an envelope conformation, with Cu—N = 2.017 (2) Å, Cu—OCOO = 1.968 (1) Å and Cu—OOH = 2.473 (2) Å. The [Cu(He‐ala)2] molecules are involved in a network of O—H⋯O and N—H⋯O hydrogen bonds, forming layers parallel to the (10) plane. The layers are connected into a three‐dimensional structure by van der Waals interactions, so that the molecular centres form pseudo‐face‐centered close packing. 相似文献
7.
K. Rajalakshmi Vasantha Pattabhi C. S. Venkatesan G. Nadamuni A. Srikrishna 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):e307-e308
In the title compound, C29H42O4·H2O, cyclohexane rings A and B are in the sofa conformation, ring C is in a chair conformation and the five‐membered ring D is in an envelope conformation. The structure is stabilized by inter‐ and intramolecular C—H?O and O—H?O hydrogen bonds. 相似文献
8.
Monica Schneider Anthony Linden Andreas Rippert 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1004-1006
The title compounds are diastereoisomers with antipodean axial chirality. The M isomer crystallizes as a (1/3) acetone solvate, C32H30NO+·Br?·3C3H6O, while the P isomer crystallizes as a (1/1) dichloromethane solvate, C32H30NO+·Br?·CH2Cl2. In each structure, O—H?Br hydrogen bonds link the cations and anions to give ion pairs. The seven‐membered azepinium ring adopts the usual twisted‐boat conformation and its ring strain causes a slight curvature of the plane of each naphthyl ring. 相似文献
9.
Yoshinobu Inouye 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e361-e362
The reduction of (1R,8R,11R)‐3,3,11‐trimethyl‐6,6‐ethylenedioxybicyclo[6.3.0]undecan‐2‐one, C16H26O3, (I), gave exclusively an alcohol, C16H28O3, (II). The stereochemistry of the hydroxyl group in (II) was shown as R. The conformation around the eight‐membered carbocycle in (I) differs markedly from that in (II). 相似文献
10.
Rafael Roggenbuck Markus Schürmann Hans Preut Peter Eilbracht 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e356-e356
The title compound, C12H16O4, (I), was prepared by oxidation of (5S*,6R*)‐1,7‐dioxadispiro[4.0.4.4]tetradecane‐2,8‐diol using silver(I) carbonate and posesses a cis configuration of the two five‐membered‐ring lactones fused spiro to the six‐membered carbocycle, which has a chair conformation. It represents an exceptional structure for bis‐tetrahydrofuran units, which are interesting building blocks in natural products. The synthesis, spectroscopic data and X‐ray structural analysis are described. The crystal contains discrete molecules separated by normal van der Waals distances. 相似文献
11.
G. Vasuki S. Thamotharan V. Parthasarathi K. Ramamurthi S. Dubey D. P. Jindal 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):o598-o599
The title compound, C32H45N2O+·Br?·0.5H2O, has the outer two six‐membered rings in chair conformations, while the central ring is in an 8β,9α‐half‐chair conformation. The five‐membered ring of the steroid nucleus adopts a slightly deformed 14α‐envelope conformation. The pyridylmethylene moiety has an E configuration with respect to the hydroxyl group at position 17. The structure is stabilized by a network of O—H?Br‐type intermolecular hydrogen bonds. 相似文献
12.
Sang Woo Cho Yongkee Cho Dae‐Kee Kim Whanchul Shin 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):653-654
In the title compound, [Pt(C3H2O4)(C7H16N2O2)], the Pt atom is coordinated to two O and two N atoms in a square‐planar arrangement. The two independent molecules, which have very similar structures, are approximately related by pseudo‐twofold screw‐axis symmetry. The six‐membered chelate ring in the leaving ligand assumes a conformation intermediate between the half‐chair and boat forms. The seven‐membered ring in the carrier ligand assumes a twist‐chair conformation and the oxolane ring assumes an envelope conformation. The crystal packing consists of extensive hydrogen‐bonding networks which form two‐dimensional molecular layers, and there are weak van der Waals interactions between these layers. 相似文献
13.
G. Vasuki V. Parthasarathi K. Ramamurthi D. P. Jindal S. Dubey 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1062-1063
The title compound, C25H31NO2·H2O, has the outer two six‐membered rings in chair conformations, while the central ring is in an 8β,9α‐half‐chair conformation. The five‐membered ring adopts a 13,14‐half‐chair conformation. The pyridylmethylene moiety has an E configuration with respect to the carbonyl group at position 17. The structure is stabilized by intermolecular O—H?N and O—H?O hydrogen bonds. 相似文献
14.
Maria Gdaniec Elbieta Nowak Maria J. Milewska Tadeusz Pooski 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o661-o662
The molecule of the title compound, C8H11NO2, contains a strained bicyclic system with a significantly twisted imide chromophore. The five‐membered ring fragment containing the imide function is strongly puckered and adopts a half‐chair conformation. The six‐membered ring has a slightly distorted chair conformation. The molecules are joined by strong N—H?O and weak C—H?O hydrogen bonds into infinite chains. 相似文献
15.
Brian Frstrup Dan Peters Andrew D. Bond 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(8):o298-o301
The title compound, C15H16NS+·C2H3O2−, has been crystallized as both a pure enantiomer (1S,5R) and a racemate. The racemate crystallizes in the space group Cc, with molecules of opposite handedness related to each other by the action of the c‐glide. The enantiomer is essentially isostructural with the racemate, except that the glide symmetry is violated by interchange of CH and CH2 groups within the seven‐membered ring. The space‐group symmetry is reduced to P1 with two molecules in the asymmetric unit. The enantiomer structure shows disorder of the thiophene ring for one of the molecules in the asymmetric unit. The major component of the disorder has the thiophene ring in the same position as in the racemate, but generates a higher‐energy molecular conformation. The minor disorder component has different intermolecular interactions but retains a more stable molecular conformation. 相似文献
16.
Silvia Russi Helena Pardo Horacio Heinzen Eduardo Dias Patrick Moyna Raúl A. Mariezcurrena Leopoldo Suescun Alvaro W. Mombrú 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):672-673
The structure of the adduct of eucarvone with nitrosobenzene, C16H19NO2, is reported. The [3.2.2] bicyclic system corresponds to two seven‐membered rings in boat and distorted chair conformations and a six‐membered ring that adopts a distorted boat conformation. No conjugation is observed between the phenyl group and the N—O system. The packing is directed mainly by a C?O hydrogen bond, C—H?O‐(1 ? x, ?y, z) and by intermolecular C—H?π interactions. 相似文献
17.
Gary S. Nichol Francis N. Murigi Eugene A. Mash 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(6):o302-o304
Synchrotron radiation was used to study the structure of the title compound, C20H19BrN2O3·C3H7NO, which was obtained as fine fragile needle‐shaped crystals by recrystallization from dimethylformamide (DMF), one molecule of which is incorporated per asymmetric unit into the crystal. The compound adopts a compact closed conformation with the orientation of the benzyl group such that the aryl ring is positioned over the piperazinedione ring, resulting in a Cspiro...Ctrans—C—CPh pseudo‐torsion angle of −3.3 (3)°. The five‐membered ring is present in an expected envelope conformation and the six‐membered piperazinedione ring adopts a less puckered boat‐like conformation. Reciprocal amide‐to‐amide hydrogen bonding between adjacent piperazinedione rings and C—H...O interactions involving DMF molecules propagate in the crystal as a thick ribbon in the a‐axis direction. 相似文献
18.
Tomohiro Matsumoto Taisuke Matsumoto Masataka Watanabe Shuntaro Mataka Thies Thiemann 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o501-o502
In the title compound, C21H25N3O, the six‐membered ring that is fused to two other six‐membered rings in the estrane moiety adopts an envelope conformation. The compound shows intermolecular hydrogen bonding of the amine group to an N atom of the pyrimidine moiety, as well as weak intermolecular interactions involving H atoms in the hydrophobic residue of the molecule. 相似文献
19.
Vitor F. Ferreira Antonio V. Pinto Maria C. R. F. Pinto Milton N. da Silva Janet M. S. Skakle Maria C. B. V. de Souza Solange M. S. V. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o560-o562
The central six‐membered ring in the title compound, C16H16O3, is almost planar (and almost coplanar with the aromatic ring), despite one of its C atoms being formally sp3 hybridized. The planarity is a consequence of the C atom at the centre of the spirocyclic system also being part of the three‐membered epoxide ring. The molecules are linked by π–π and C—H?π interactions. 相似文献
20.
L. C. R. Andrade J. A. Paixo M. J. M. de Almeida E. J. Tavares da Silva M. L. S e Melo F. M. Fernandes Roleira 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o82-o83
The title compound, alternatively called 24‐nor‐5β‐chol‐22‐ene‐3β,7α,12α‐triyl triformate, C26H38O6, has a cis junction between two of the six‐membered rings. All three of the six‐membered rings have chair conformations that are slightly flattened and the five‐membered ring has a 13β,14α‐half‐chair conformation. The 3β, 7α and 12α ring substituents are axial and the 17β group is equatorial. The 3β‐formyloxy group is involved in one weak intermolecular C—H⋯O bond, which links the molecules into dimers in a head‐to‐head fashion. 相似文献