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1.
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
2.
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
3.
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
4.
John N. Low Debbie Cannon Antonio Quesada Antonio Marchal Manuel Melguizo Manuel Nogueras Adolfo Snchez Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):604-607
In the title compound, 2C10H15N5O4·0.5H2O, there are two independent molecules of the pyrimidinylisoleucine in general positions and a water molecule lying on a twofold rotation axis. The bond lengths within the organic moieties demonstrate significant polarization of the electronic structure. Each of the organic molecules participates in 12 intermolecular hydrogen bonds, of O—H?O and N—H?O types, while the water molecule acts as a double donor and as a double acceptor of O—H?O hydrogen bonds. The organic components are linked by the hydrogen bonds into a single three‐dimensional framework, reinforced by the water molecules. 相似文献
5.
Carlo Andrea Mattia Alessandra Braca Nunziatina De Tommasi Raffaella Puliti 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):o644-o646
The title tetracyclic diterpenoid, 10,13,16,17‐tetrahydroxy‐9‐methyl‐15‐oxo‐20‐norkaurane‐18,10‐carbolactone hemihydrate, C20H28O6·0.5H2O, is a plant metabolite from Parinari sprucei, part of the Venezuelan Amazon flora. The asymmetric unit consists of two nearly identical molecules of the diterpenoid and one molecule of water. Some of the geometric parameters reflect steric strain in the molecule. The extended structure is characterized by hydrogen bonds and weaker hydrogen‐mediated interactions, which involve all of the hydroxy groups and propagate in sheets that coincide with the (002) family of planes. The water molecule acts as a double hydrogen‐bond donor and single acceptor and thus plays a critical role in the pattern of intermolecular interactions. 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.
S. Shanmuga Sundara Raj Hoong‐Kun Fun Zhong‐Lin Lu Wen Xiao Xiao‐Yang Gong Chang‐Ming Gen 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1015-1016
The whole molecule of the title compound, C19H14N4O2, is essentially planar, with a highly conjugated π system. In the crystal, the molecules are packed as chains along the [011] direction connected by O—H?N intermolecular hydrogen bonds. 相似文献
8.
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
9.
A. Subbiah Pandi D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun M. C. Bansal 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o302-o304
The title compound, C19H20O6, crystallizes in the centrosymmetric space group P21/c with one molecule in the asymmetric unit. The molecule is approximately planar and the dihedral angle between the phenyl rings is 11.0 (1)°. The H atoms of the central propenone group are trans. There is an intramolecular O—H⃛O hydrogen bond and the molecules are crosslinked by four intermolecular C—H⃛O hydrogen bonds, producing a three‐dimensional network. 相似文献
10.
Rudy L. Luck G. David Mendenhall 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):602-603
The title compound, C14H21NO, has two molecules in the asymmetric unit. Each molecule forms hydrogen‐bonded dimers about inversion centers via O—H?N hydrogen bonds between oxime groups. The N—O distances in the oxime groups are 1.4160 (15) and 1.4131 (14) Å. 相似文献
11.
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
12.
Tomasz Klis Sergiusz Lulinski Janusz Serwatowski 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o145-o146
The molecule of the title compound, 2,3‐F2‐4‐(CHO)C6H2B(OH)2 or C7H5BF2O3, contains a formyl group coplanar with the benzene ring. The boronic acid group is twisted with respect to the benzene ring plane. The molecules are organized into infinite chains via intermolecular O—H⋯O hydrogen bonds. These chains are additionally connected via strong O—H⋯O hydrogen bonds, producing a folded layer structure perpendicular to the a axis. These layers are paired due to B⋯F interactions. 相似文献
13.
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
14.
Chao Tu Dun‐Ru Zhu Yan Xu Xiao‐Kang Ke Zijian Guo 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1334-1335
The title compound, C11H8N2O, has two crystallographically independent molecules in the crystal. Each molecule is basically planar except for the O atom. The two N atoms in the molecule show different behaviour as hydrogen‐bonding acceptors. One of them is involved in intermolecular O—H?N hydrogen bonds which stabilize the crystal packing. 相似文献
15.
Dianne D. Ellis Anthony L. Spek 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):497-498
In the crystal structure of C15H20O2, molecules are associated by intermolecular hydrogen bonds between the hydroxy function and a keto group [O?O 2.770 (2) Å], forming chains along the [100] direction in the crystal. Both six‐membered rings in the decalin unit adopt envelope conformations; one section of the molecule, encompassing the extended conjugation of a C=C double bond with an enone functionality [C=C—C=O = 175.6 (2)° and C=C—C=C = 176.6 (2)°], is flat, whilst the rest of the molecule is folded relative to the constrained part. The stereochemistry was determined from the R‐(–)‐carvone starting material. 相似文献
16.
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
17.
Li‐Ping Lu Si‐Si Feng Hong‐Mei Zhang Miao‐Li Zhu 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):m283-m284
The crystal structure of the title compound, [Cu2(C12H7N2O)2]·H2O, shows that this dinuclear complex has shorter Cu—N, Cu—O and Cu—Cu distances within the coordination sphere than similar reported complexes. The complex molecule is located on a centre of symmetry and the water molecule is on a twofold axis of the space group C2/c. The discrete complex molecules are extended into a two‐dimensional supramolecular array viaπ–π stacking interactions, intermolecular Cu⋯Cu interactions and C—H⋯O hydrogen bonds. 相似文献
18.
Gordana Pavlovi Julija Matijevi Sosa 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1117-1119
The title compound, C18H13NO3, exists as a ketoamino tautomer implying a fairly short N—H?O intramolecular hydrogen bond between the 2‐naphthalenone and amino moieties [N?O 2.531 (3) Å] which is enhanced by the π‐electron delocalization effect. The naphthaldimine and 3‐carboxyphenyl fragments are inclined at an angle of 4.41 (7)°, so the molecule is almost planar. The molecules are connected by intermolecular O—H?O hydrogen bonds between the carboxy and keto O atoms, forming infinite chains around the twofold screw axes parallel to b . 相似文献
19.
Vladimir N. Nesterov Volodymyr V. Nesterov 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o781-o785
Two new polymorph forms, (Ia) and (Ib), of the title compound, C14H17N3S, and its solvate with acetonitrile, C14H17N3S·0.25C2H3N, (Ic), have been investigated. Crystals of the two polymorphs were grown from different solvents, viz. ethanol and N,N‐dimethylformamide, respectively. The polymorphs have different orientations of the thioamide group relative to the CN substituent, with s‐cis and s‐trans geometry of the C=C—C=S diene fragment, respectively. Compound (Ic) contains two independent molecules, A and B, with s‐cis geometry, and the solvate molecule lies on a twofold axis. The core of each molecule is slightly non‐planar; the dihedral angles between the conjugated C=C—CN linkage and the phenyl ring, and between this linkage and the thioamide group are 13.4 (2) and 12.0 (2)° in (Ia), 14.0 (2) and 18.2 (2)° in (Ib), 2.3 (3) and 12.7 (4)° in molecule A of (Ic), and 23.2 (3) and 8.1 (4)° in molecule B of (Ic). As a result of strong conjugation between donor and acceptor parts, the substituted phenyl rings have noticeable quinoid character. In (Ib), there exists a very strong intramolecular steric interaction (H⋯H = 1.95 Å) between the bridging and thioamide parts of the molecule, which makes such a form less stable. In the crystal structure of (Ia), intermolecular N—H⋯N and N—H⋯S hydrogen bonds link molecules into infinite tapes along the [10] direction. In (Ib), such intermolecular hydrogen bonds link molecules into infinite (101) planes. In (Ic), intermolecular N—H⋯N hydrogen bonds link molecules A and B into dimers, which are connected via N—H⋯S hydrogen bonds and form infinite chains along the c direction. 相似文献
20.
Ying Xu Hong‐Xi Li Wen‐Hua Zhang Yong Zhang Jian‐Ping Lang 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):m4-m6
In the title compound, [Cu2I2(C11H16N4)2], each of the two crystallographically equivalent Cu atoms is tetrahedrally coordinated by two N atoms from one 1,1′‐methylenebis(3,5‐dimethyl‐1H‐pyrazole) ligand and two bridging iodide anions. The molecule has a crystallographic center of symmetry located at the mid‐point of the Cu·Cu line. One H atom of the CH2 group of the 1,1′‐methylenebis(3,5‐dimethyl‐1H‐pyrazole) ligand interacts with an iodide ion in an adjacent molecule to afford pairwise intermolecular C—H·I contacts, thereby forming chains of molecules running along the [101] direction. 相似文献