共查询到20条相似文献,搜索用时 31 毫秒
1.
Fabrice Camus Bernadette Norberg Anne Legrand Benoit Rigo Franois Durant Johan Wouters 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):193-196
In the course of a study on pyrrolidinones, the crystal structures of four compounds, namely, methyl N‐[(4‐methoxyphenyl)(3,4,5‐trimethoxyphenyl)methyl]pyroglutamate, C23H27NO7, methyl N‐[naphthyl‐(3,4,5‐trimethoxyphenyl)methyl]pyroglutamate diacetyl peroxide, C26H27NO6·‐0.5C4H6O4, 5‐(3,4,5‐trimethoxyphenyl)‐1,2,3,11b‐tetrahydro‐5H‐naphtho[1,8‐f,g]indolizin‐3‐one, C24H23NO4, and 5‐(3,4,5‐trimethoxyphenyl)‐1,2,3,5,12,12a‐hexahydronaphtho[1,2‐f]indolizine‐3,12‐dione, C25H23NO5, are presented, compared and discussed. 相似文献
2.
Marc Rolland Tarek Kassem Valérie Rolland Jean Martinez 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1415-1417
We present the crystal and molecular structures of 2,3,6,7,8,8a-hexahydro-6,8-methano-7,7,8a-trimethyl-3-(1-methyl-2-oxopropylidene)-5H-1,4-benzoxazin-2-one, C16H21NO3, (III), and 2,3,6,7,8,8a-hexahydro-3-(2-hydroxy-1-methylpropyl)-6,8-methano-7,7,8a-trimethyl-5H-1,4-benzoxazin-2-one, C16H25NO3, (V). These compounds are two of the four key intermediates in our synthetic route to (2R,3R,4R)-4-hydroxyisoleucine. The two structures provide a full understanding of the stereochemistry in successive steps. This synthesis was based on a new optically pure chiral oxazinone auxiliary derived from (1R,2R,5R)-2-hydroxypinan-3-one. 相似文献
3.
Dens Konya Christian Philouze Yves Gimbert Andrew E. Greene 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o108-o111
Three chiral electron‐deficient phosphine ligands, [(4R,15R)‐,3‐bis(trifluoromethanesulfonyl)perhydro‐1,3,2‐benzodiazaphosphol‐2‐yl]diethylamine, C12H20F6N3O4PS2, (IIIa), [(4R,5R)‐1,3‐bis(trifluoromethanesulfonyl)perhydro‐1,3,2‐benzodiazaphosphol‐2‐yl]dimethylamine, C10H16F6N3O4PS2, (IIIb), and bis[(4R,5R)‐1,3‐bis(trifluoromethanesulfonyl)perhydro‐1,3,2‐benzodiazaphosphol‐2‐yl]methylamine, (IV), as the chloroform solvate, C17H23F12N5O8P2S4·0.98CHCl3, have been prepared from (1R,2R)‐N,N′‐bis(trifluoromethanesulfonyl)‐1,2‐cyclohexanediamine and diethyl phosphoramidous dichloride, dimethyl phosphoramidous dichloride or methyl imidodiphosphorus tetrachloride. The π‐acceptor abilities of these new types of ligands have been evaluated by X‐ray determination of the P—N bond lengths; it has been found that the most promising ligand is the bis(phosphine) (IV). 相似文献
4.
A. Sivalakshmidevi K. Vyas G. Om Reddy 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):e115-e116
The title compound, sparfloxacin or cis‐5‐amino‐1‐cyclopropyl‐7‐(3,5‐dimethylpiperazin‐1‐yl)‐6,8‐difluoro‐1,4‐dihydro‐4‐oxoquinoline‐3‐carboxylic acid trihydrate, C19H22F2N4O3·3H2O, is an antibacterial drug. The molecule, which crystallizes as a trihydrate, is in the zwitterionic form in the solid state. Hydrogen bonds stabilize the molecules in the lattice. 相似文献
5.
Jianping Zhao Ilias Muhammad D. Chuck Dunbar Ikhlas A. Khan Nikolaus H. Fischer Frank R. Fronczek 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o195-o198
A low‐temperature structure of ginkgolide A monohydrate, (1R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11aS)‐3‐(1,1‐dimethylethyl)‐hexahydro‐4,7b‐dihydroxy‐8‐methyl‐9H‐1,7a‐epoxymethano‐1H,6aH‐cyclopenta[c]furo[2,3‐b]furo[3′,2′:3,4]cyclopenta[1,2‐d]furan‐5,9,12(4H)‐trione monohydrate, C20H24O9·H2O, obtained from Mo Kα data, is a factor of three more precise than the previous room‐temperature determination. A refinement of the ginkgolide A monohydrate structure with Cu Kα data has allowed the assignment of the absolute configuration of the series of compounds. Ginkgolide C sesquihydrate, (1S,2R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11S,11aR)‐3‐(1,1‐dimethylethyl)‐hexahydro‐2,4,7b,11‐tetrahydroxy‐8‐methyl‐9H‐1,7a‐epoxymethano‐1H,6aH‐cyclopenta[c]furo[2,3‐b]furo[3′,2′:3,4]cyclopenta[1,2‐d]furan‐5,9,12(4H)‐trione sesquihydrate, C20H24O11·1.5H2O, has two independent diterpene molecules, both of which exhibit intramolecular hydrogen bonding between OH groups. Ginkgolide J dihydrate, (1S,2R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11aS)‐3‐(1,1‐dimethylethyl)‐hexahydro‐2,4,7b‐trihydroxy‐8‐methyl‐9H‐1,7a‐epoxymethano‐1H,6aH‐cyclopenta[c]furo[2,3‐b]furo[3′,2′:3,4]cyclopenta[1,2‐d]furan‐5,9,12(4H)‐trione dihydrate, C20H24O10·2H2O, has the same basic skeleton as the other ginkgolides, with its three OH groups having the same configurations as those in ginkgolide C. The conformations of the six five‐membered rings are quite similar across ginkgolides A–C and J, except for the A and F rings of ginkgolide A. 相似文献
6.
Peter G. Jones Ludger Ernst Ina Dix Lars Wittkowski 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):239-241
The [2.2]paracyclophane groups of the title compounds, chiral and meso‐bis(tricyclo[8.2.2.24,7]hexadeca‐4,6,10,12,13,15‐hexaen‐5‐yl)methane (the former as a racemate), C33H32, and meso‐bis(tricyclo[8.2.2.24,7]hexadeca‐4,6,10,12,13,15‐hexaen‐5‐yl) sulfide, C32H30S, show the characteristic structural features of the parent compound [2.2]paracyclophane and the related compound dimethylbis([2.2]paracyclophan‐4‐yl)silane, C34H36Si: the aromatic rings are puckered, resulting in a boat conformation. The planes of the four coplanar C atoms are slightly twisted with respect to each other. The Csp3—Csp3 bond lengths of the ethylene bridges are elongated by the electronic and steric effects of the skeleton. 相似文献
7.
Prakas R. Maulik Kamlakar Avasthi Sanjay Sarkhel Tilak Chandra Diwan S. Rawat Brad Logsdon Robert A. Jacobson 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1361-1363
In the crystal structures of 4,6‐dimethylthio‐1‐[3‐(4,6‐dimethylthio‐2H‐pyrazolo[3,4‐d]pyrimidin‐2‐yl)propyl]‐1H‐pyrazolo[3,4‐d]pyrimidine, C17H20N8S4, and 1‐[4‐(4‐methoxy‐6‐methylthio‐1H‐pyrazolo[3,4‐d]pyrimidin‐1‐yl)butyl]‐5‐methyl‐6‐methylthio‐4,5‐dihydro‐1H‐pyrazolo[3,4‐d]pyrimidin‐4‐one, C18H22N8O2S2, only intermolecular stacking due to aromatic π–π interactions between pyrazolo[3,4‐d]pyrimidinerings is present. 相似文献
8.
R. Malathi S. S. Rajan G. Suresh G. N. Krishnakumari G. Gopalakrishnan 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):o416-o418
Samaderin B, or (1R,2S,5R,5aR,7aS,11S,11aS,11bR,14S)‐1,7,7a,11,11a,11b‐hexahydro‐1,11‐dihydroxy‐8,11a,14‐trimethyl‐2H‐5a,2,5‐(methanoxymetheno)naphth[1,2‐d]oxepine‐4,6,10(5H)‐trione, C19H22O7, and samaderin C, or (1R,2S,5R,5aR,7aS,10S,11S,11aS,11bR,14S)‐7,7a,10,11,11a,11b‐hexahydro‐1,10,11‐trihydroxy‐8,11a,14‐trimethyl‐2H‐5a,2,5‐(methanoxymetheno)naphth[1,2‐d]oxepine‐4,6(1H,5H)‐dione, C19H24O7, were isolated from the seed kernels of Samadera indica and were shown to exhibit antifeedant activity against Spodoptera litura third‐instar larvae. The replacement of the carbonyl group in samaderin B by a hydroxy group in samaderin C causes conformational changes at the substitution site, but the overall conformation is not affected; however, the compounds pack differently in the crystal lattice. 相似文献
9.
Bartosz Zarychta Anna Piecyk‐Mizgaa Zdzisaw Daszkiewicz Jacek Zaleski 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):o515-o517
The structures of the two title isomeric compounds (systematic names: N‐methyl‐N,2‐dinitroaniline and N‐methyl‐N,3‐dinitroaniline, both C7H7N3O4) are slightly different because they exhibit different steric hindrances and hydrogen‐bonding environments. The aromatic rings are planar. The –N(Me)NO2 and –NO2 groups are not coplanar with the rings. Comparison of the geometric parameters of the ortho, meta and para isomers together with those of N‐methyl‐N‐phenylnitramine suggests that the position of the nitro group has a strong influence on the aromatic ring distortion. The crystal packing is stabilized by weak C—H⋯O hydrogen bonds to the nitramine group. 相似文献
10.
Jan ejka Bohumil Kratochvíl Ivana Císaov Alexandr Jegorov 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):o428-o430
Simvastatin, or (1S,3R,7S,8S,8aR)‐8‐{2‐[(2R,4R)‐4‐hydroxy‐6‐oxo‐3,4,5,6‐tetrahydro‐2H‐pyran‐2‐yl]ethyl}‐3,7‐dimethyl‐1,2,3,7,8,8a‐hexahydronaphthalen‐1‐yl 2,2‐dimethylbutanoate, C25H38O5, is almost isostructural with lovastatin, and the general conformational features are closely related to those of other reported crystal structures of statins. The only hydrogen bond present facilitates the formation of infinite chains of molecules along the b axis. 相似文献
11.
Jose G. Trujillo‐Ferrara Rosa Luisa Santilln‐Baca Norberto Farfn‐García Itzia I. Padilla‐Martínez Efrn V. García‐Bez 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(3):o125-o128
The molecular and supramolecular structures of 2‐(1,3‐dioxo‐2,3,3a,4,7,7a‐hexahydro‐1H‐isoindol‐2‐yl)phenyl acetate, C16‐H15NO4, (I), and its para isomer, 4‐(1,3‐dioxo‐2,3,3a,4,7,7a‐hexahydro‐1H‐isoindol‐2‐yl)phenyl acetate, (II), are reported. The torsion angle between the succinimide and benzene rings depends on the position of the acetoxy substitution [89.7 (1) and 61.9 (1)° for (I) and (II), respectively]. The twist of the acetoxy group relative to the mean plane of the benzene ring is almost independent of the acetoxy position [66.0 (1) and 70.0 (1)°]. Packing interactions for both compounds include soft C—H⋯X (X = O and Ph) interactions, forming chains of centrosymmetric dimers and interlinked chains for (I) and (II), respectively. In addition, three perpendicular dipole C=O⋯C=O interactions contribute to the supramolecular structure of (II). 相似文献
12.
C. Foces‐Foces M. L. Rodríguez M. Febles C. Prez J. D. Martín 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):o339-o342
The crystal structures of 7,7‐dicyclobutyl‐5‐hydroxymethyl‐6‐oxabicyclo[3.2.1]octane‐1‐carboxylic acid, C17H26O4, (I), and 1‐(hydroxymethyl)‐7‐oxaspiro[bicyclo[3.2.1]octane‐6,1′‐cyclopentane]‐5‐carboxylic acid, C13H20O4, (II), determined at 170 K, show that the conformation of the hydroxymethyl group (anti or gauche) affects the dimensionality (one‐ or two‐dimensional) of the supramolecular structures via O—H⋯O hydrogen bonds. In (I), the carboxyl and hydroxymethyl groups interact with themselves, forming a one‐dimensional step‐ladder, while in (II), a two‐dimensional structure is made up of carboxylic acid centrosymmetric R22(8) dimers connected by hydroxyl‐to‐ether contacts. 相似文献
13.
Krishnan Ravikumar Balasubramanian Sridhar 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):o478-o482
Moxifloxacin, a novel fluoroquinolone with a broad spectrum of antibacterial activity, is available as the solvated monohydrochloride salt 7‐[(S,S)‐2‐aza‐8‐azoniabicyclo[4.3.0]non‐8‐yl]‐1‐cyclopropyl‐6‐fluoro‐8‐methoxy‐4‐oxo‐1,4‐dihydroquinoline‐3‐carboxylic acid chloride–water–methanol (2/1/1), C21H25FN3O4+·Cl−·0.5H2O·0.5CH3OH. The asymmetric unit contains two cations, two chloride ions, a molecule of water and one methanol molecule. The two cations adopt conformations that differ by an almost 180° rotation with respect to the piperidinopyrrolidine side chain. The cyclopropyl ring and the methoxy group are not coplanar with the quinoline ring system. The carboxylic acid function, the protonated terminal piperidyl N atom, the water molecule, the chloride ion and the methanol molecule participate in O—H⋯O, O—H⋯Cl, N—H⋯O and N—H⋯Cl hydrogen bonding, linking the molecules into extended two‐dimensional networks. 相似文献
14.
Mason A. Wolak Robert C. Finn Randy S. Rarig Craig J. Thomas Robert P. Hammond Robert R. Birge Jon Zubieta Watson J. Lees 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):o389-o393
Fluorinated indolylfulgides are a class of photochromic organic compounds that meet many of the requirements for use as optical memory media and optical switches. The X‐ray crystal structures of a series of five photochromic fluorinated indolylfulgides have been determined, namely (3Z)‐3‐[1‐(1,2‐dimethyl‐1H‐indol‐3‐yl)‐2,2,2‐trifluoroethylidene]‐4‐(1‐methylethylidene)dihydrofuran‐2,5‐dione (trifluoromethylisopropylideneindolylfulgide), C19H16F3NO3, (I), (3Z)‐3‐[1‐(1,2‐dimethyl‐1H‐indol‐3‐yl)‐2,2,3,3,3‐pentafluoropropylidene]‐4‐(1‐methylethylidene)dihydrofuran‐2,5‐dione (pentafluoroethylisopropylideneindolylfulgide), C20H16F5NO3, (II), (3Z)‐3‐[1‐(1,2‐dimethyl‐1H‐indol‐3‐yl)‐2,2,3,3,4,4,4‐heptafluorobutylidene]‐4‐(1‐methylethylidene)dihydrofuran‐2,5‐dione (heptafluoropropylisopropylideneindolylfulgide), C21H16F7NO3, (III), (3Z)‐3‐[1‐(1,2‐dimethyl‐1H‐indol‐3‐yl)‐2,2,2‐trifluoroethylidene]‐4‐(tricyclo[3.3.1.13,7]decylidene)dihydrofuran‐2,5‐dione (trifluoromethyladamantylideneindolylfulgide), C26H24F3NO3, (IV), and (3Z)‐3‐[1‐(1,2‐dimethyl‐1H‐indol‐3‐yl)‐2,2,3,3,4,4,4‐heptafluorobutylidene]‐4‐(tricyclo[3.3.1.13,7]decylidene)dihydrofuran‐2,5‐dione (heptafluoropropyladamantylideneindolylfulgide), C28H24F7NO3, (V). The photochromic property of fulgides is based on the photochemically allowed electrocyclic ring closure of a hexatriene system to form a cyclohexadiene. For each fulgide examined, the bond lengths within the hexatriene system alternate between short and long, as expected. Comparing the structures of the five fulgides with each other demonstrates no significant difference in bond lengths, bond angles or dihedral angles within the hexatriene systems. The distance between the bond‐forming C atoms at each end of the hexatriene system does vary. Correlations of structural properties with optical properties are addressed. 相似文献
15.
Shiming Li Knut Lundquist Vratislav Langer 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):o625-o627
Compounds (2R*,3S*)‐1‐(3,4‐dimethoxyphenyl)‐3‐{3‐methoxy‐2‐[(2R*)‐tetrahydropyran‐2‐yloxy]phenyl}‐2,3‐epoxy‐1‐propanone, C23H26O7, (I), and trans‐1‐(3,4‐dimethoxyphenyl)‐3‐[3‐methoxy‐2‐(methoxymethoxy)phenyl]‐2,3‐epoxy‐1‐propanone, C20H22O7, (II), were obtained on epoxidation of chalcones. The stereochemistries of (I) and (II) were elucidated. In both compounds, the substituents on the oxirane ring are trans‐oriented. Compound (I) was obtained together with a diastereometric form that differs from (I) with respect to the configuration of the asymmetric C atom in the tetrahydropyran group. The geometries of the substituted oxirane rings of (I) and (II) are very similar. The hydrogen‐bonding patterns, mediated via weak C—H⋯O interactions, differ considerably. The crystal structures of (I) and (II) are compared with those of related chalcone epoxides. The conversion of (I) and (II) into lignin‐related phenylcoumarans is discussed. 相似文献
16.
Ning‐Hai Hu Yasuhiro Kiyota Katsuyuki Aoki 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1284-1286
In the title compound, 3‐[(3,4‐dihydro‐2‐methyl‐4‐oxopyrimidin‐5‐yl)methyl]‐5‐(2‐hydroxyethyl)‐4‐methylthiazolium hexafluorophosphate monohydrate, C12H16N3O2S+·PF6?·H2O, oxythiamine is a monovalent cation with a neutral oxopyrimidine ring. The molecule assumes the F conformation, which is a common form for thiamine but which is substantially different from the unusual V conformation found in the chloride and hydrochloride salts of oxythiamine. The anion‐bridging interaction, C—H?anion?pyrimidine, is emphasized as being important for stabilization of the F conformation. 相似文献
17.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o1-o5
The crystal structures of four trifluoromethylnitrobenzene analogues (CF3)C6H3(NO2)[C4H8N2]R (where C4H8N2 is piperazinyl and R is ethyl carboxylate, CO2C2H5, or phenyl, C6H5), have been determined, and their conformations and packing arrangements are compared. The four compounds are ethyl 4‐[4‐nitro‐2‐(trifluoromethyl)phenyl]piperazine‐1‐carboxylate, (I), and ethyl 4‐[2‐nitro‐4‐(trifluoromethyl)phenyl]piperazine‐1‐carboxylate, (II), both C14H16F3N3O4, and 1‐[4‐nitro‐2‐(trifluoromethyl)phenyl]‐4‐phenylpiperazine, (III), and 1‐[2‐nitro‐4‐(trifluoromethyl)phenyl]‐4‐phenylpiperazine, (IV), both C17H16F3N3O2. All molecules adopt a rod‐like conformation, while the asymmetric units of (II) and (IV) contain two unique molecules that pack as monodirectional pairs. All molecules pack with C—H⋯O/F close contacts to all but one of the O atoms and to five of the 18 F atoms. 相似文献
18.
Arthur Camerman Andrew Hempel Donald Mastropaolo Norman Camerman 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(7):o417-o419
In the crystal structure of 2‐acetamido‐N‐benzyl‐2‐(methoxyamino)acetamide (3L), C12H17N3O3, the 2‐acetylaminoacetamide moiety has a linearly extended conformation, with an interplanar angle between the two amide groups of 157.3 (1)°. In 2‐acetamido‐N‐benzyl‐2‐[methoxy(methyl)amino]acetamide (3N), C13H19N3O3, the planes of the two amide groups intersect at an angle of 126.4 (4)°, resulting in a chain that is slightly more bent. The replacement of the methoxyamino H atom of 3L with a methyl group to form 3N and concomitant loss of hydrogen bonding results in some positional/thermal disorder in the methoxy(methyl)amino group. In both structures, in addition to classical N—H⋯O hydrogen bonds, there are also weak non‐standard C—H⋯O hydrogen bonds. The hydrogen bonds and packing interactions result in planar hydrophilic and hydrophobic areas perpendicular to the c axis in 3L and parallel to the ab plane in the N‐methyl derivative. Stereochemical comparisons with phenytoin have identified two O atoms and a phenyl group as molecular features likely to be responsible for the anticonvulsant activities of these compounds. 相似文献
19.
Anne M. Sauer Frank R. Fronczek Betty C. R. Zhu William E. Crowe Gregg Henderson Roger A. Laine 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):o254-o256
Nootkatone, or (4R,4aS,6R)‐4,4a,5,6,7,8‐hexahydro‐4,4a‐dimethyl‐6‐(1‐methylethenyl)naphthalen‐2(3H)‐one, C15H22O, a sesquiterpene with strong repellent properties against Formosan subterranean termites and other insects, has the valencene skeleton. The dibromo derivative (1S,3R,4S,4aS,6R,8aR)‐1,3‐dibromo‐6‐isopropyl‐4,4a‐dimethyl‐1,2,3,4,5,6,7,8‐octahydronaphthalen‐2‐one, C15H24Br2O, has two independent molecules in the asymmetric unit, which differ in the rotation of the isopropyl group with respect to the main skeleton. The C—Br distances are in the range 1.950 (4)–1.960 (4) Å. Both independent molecules form zigzag chains, with very short intermolecular carbonyl–carbonyl interactions, having the perpendicular motif and O⋯C distances of 2.886 (6) and 2.898 (6) Å. These chains are flanked by intermolecular Br⋯Br interactions of distances in the range 4.067 (1)–4.218 (1) Å. The absolute configuration of the dibromo derivative was determined, from which that of nootkatone was inferred. 相似文献
20.
Anthony Linden Jarosaw Romaski Grzegorz Mlosto Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):o221-o226
Three cage‐like polycyclic compounds, viz.exo‐8‐(trifluoromethyl)pentacyclo[5.4.0.02,6.03,10.05,9]undecan‐endo‐8‐ol, C12H13F3O, 5‐(trifluoromethyl)‐4‐oxahexacyclo[5.4.1.02,6.03,10.05,9.08,11]dodecan‐3‐ol, C12H11F3O2, and N‐[exo‐11‐(trifluoromethyl)‐endo‐11‐(trimethylsilyloxy)pentacyclo[5.4.0.02,6.03,10.05,9]undecan‐8‐ylidene]aniline methanol solvate, C21H24F3NOSi·CH4O, were obtained from the corresponding oxo derivatives by nucleophilic trifluoromethylation with (trifluoromethyl)trimethylsilane in 1,2‐dimethoxyethane solution in the presence of CsF. The crystal structures show that the addition of trifluoromethanide occurs exclusively from the exo face of the polycyclic ketones. Further examination of the crystal structures, together with that of the starting pentacyclo[5.4.0.02,6.03,10.05,9]undecane‐8,11‐dione, C11H10O2, showed that increasing substitution at the 8‐ and/or 11‐positions in the cage molecules increases the non‐bonded intramolecular C·C distances at the mouth of the cage and changes the puckering of the five‐membered rings involving the 8‐ and 11‐positions from an envelope towards a distorted half‐chair conformation. Intermolecular co‐operative O—H·O hydrogen bonds in the endo‐8‐ol compound link the molecules into tetramers. 相似文献