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1.
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
2.
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
3.
Susanne Flock Clemens Bruhn Heinrich Fink Herbert Frauenrath 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):o101-o103
The title enantiomorphic compounds, C16H23NO4S, have been obtained in an enantiomerically pure form by crystallization from a diastereomeric mixture either of (2S,4S)‐ and (2R,4S)‐ or of (2R,4R)‐ and (2S,4R)‐2‐tert‐butyl‐4‐methyl‐3‐(4‐tolylsulfonyl)‐1,3‐oxazolidine‐4‐carbaldehyde. These mixtures were prepared by an aziridination rearrangement process starting with (S)‐ or (R)‐2‐tert‐butyl‐5‐methyl‐4H‐1,3‐dioxine. The crystal structures indicate an envelope conformation of the oxazolidine moiety for both compounds. 相似文献
4.
Ute Baumeister Helmut Hartung Roland Spitzner Michael Felicetti Werner Schroth 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):830-831
The (3R*,3′R*) configuration of the title compound, C18H16N2S2, (I), has been unambiguously elucidated by X‐ray analysis. Molecules of (I) have C2 symmetry to a good approximation and a strongly folded shape. The interplanar angle between the two halves of a molecule is 67.11 (6)°. 相似文献
5.
Tullio Pilati Gianluigi Casalone 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o178-o180
The title diastereoisomers, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate and methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, both C19H23N3O5, have been studied in two crystalline forms. The first form, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate–methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate (1/1), 2(S),5(S)‐C19H23N3O5·2(R),5(S)‐C19H23N3O5, contains both S,S and S,R isomers, while the second, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, 2(S),5(S)‐C19H23N3O5, is the pure S,S isomer. The S,S isomers in the two structures show very similar geometries, the maximum difference being about 15° on one torsion angle. The differences between the S,S and S,R isomers, apart from those due to the inversion of one chiral centre, are more remarkable, and are partially due to a possible rotational disorder of the 2‐(methoxycarbonyl)tetrahydropyrrole group. 相似文献
6.
Mark Davison Elizabeth M. Kikolski David Mostafavi Roger A. Lalancette Hugh W. Thompson 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):o249-o252
The (+)‐(αS,1S,4R)‐diastereomer of the title structure, C10H16O3, aggregates in the solid as non‐symmetric dimers with disorder in both carboxyl groups [O·O = 2.710 (5) and 2.638 (5) Å]. The two molecules constituting the asymmetric unit pair around a pseudo‐twofold rotational axis and differ only slightly in their distances and angles, but one methyl group displays rotational disorder absent in the other molecule. Five intermolecular C—H·O close contacts exist, involving both ketone groups. The (+)‐(αR,1R,4R)‐diastereomer exists in the crystal in its closed‐ring lactol form, (3R,3aR,6R,7aR)‐2,3,3a,4,5,6,7,7a‐octahydro‐7a‐hydroxy‐3,6‐dimethylbenzo[b]furan‐2‐one, C10H16O3, and aggregates as hydrogen‐bonded catemers that extend from the hydroxyl group of one molecule to the carbonyl group of a neighbor screw‐related along b [O·O = 2.830 (3) Å and O—H·O = 169°]. One close intermolecular C—H·O contact exists involving the carbonyl group. 相似文献
7.
Nada Kouti‐Hulita Miroslav
egarac 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(3):o171-o173
In the crystal structure of (R)‐N,N‐diisopropyl‐3‐(2‐hydroxy‐5‐methylphenyl)‐3‐phenylpropylaminium (2R,3R)‐hydrogen tartrate, C22H32NO+·C4H5O6−, the hydrogen tartrate anions are linked by O—H⋯O hydrogen bonds to form helical chains built from (9) rings. These chains are linked by the tolterodine molecules via N—H⋯O and O—H⋯O hydrogen bonds to form separate sheets parallel to the (101) plane. 相似文献
8.
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
9.
Manfred Zabel Josef Breu Franz Rau Klaus‐Jürgen Range Volker Krey Anka Uffrecht Armin Buschauer 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):250-251
The structural information gained from the study of the chiral building block (R)‐(?)‐4‐(3,4‐dichlorophenyl)‐4‐(2‐pyridyl)butanoic acid–l ‐(?)‐ephedrine [methyl(1‐hydroxy‐1‐phenylprop‐2‐yl)ammonium 4‐(3,4‐dichlorophenyl)‐4‐(2‐pyridyl)butanoate], C10H16NO+·C15H12Cl2NO2?, can be used to deduce the absolute configuration of highly potent arpromidine‐type histamine H2 receptor agonists, as the chiral butanoic acid can be converted to (R)‐(?)‐3‐(3,4‐dichlorophenyl)‐3‐(2‐pyridyl)propylamine and to the corresponding R‐configured arpromidine analogue. 相似文献
10.
Christopher Glidewell John N. Low Susan A. McWilliam Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o97-o99
In 2‐trifluoromethyl‐4‐nitroaniline, C7H5F3N2O2, (I), the molecules lie across a mirror plane in space group Pnma. The molecules are linked by paired N—H?O hydrogen bonds to form a C(8)[R(6)] chain of rings, pairs of which are linked into a molecular ladder by a single C—H?O hydrogen bond. The isomeric 3‐trifluoromethyl‐4‐nitroaniline, (II), has Z′ = 2 in space group P21/c. Each molecule is linked to four others by N—H?O hydrogen bonds to form sheets built from alternating R(12) and R(32) rings. 相似文献
11.
G. Mazumder M. De S. K. Mazumder A. Mukhopadhyay A. K. Das A. Van Aerschot 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):560-561
The title compound, 9(R)‐[6(R)‐hydroxymethyl‐1‐oxa‐4‐thiacyclohexan‐2‐yl]‐1,9‐dihydro‐6H‐purin‐6‐one–water (4/3), C10H12N4O3S·0.75H2O, crystallizes in the triclinic space group P1 with four molecules in the asymmetric unit and 0.75 waters of hydration per molecule. The structure was refined to an R value of 0.072 for 3382 observed reflections. The four crystallographically independent molecules are designated A, B, C and D. All four oxathiane rings adopt the chair conformation and the purine bases are in an anti orientation with respect to the sugar moieties. Molecules A and D and molecules C and B are base paired by a single hydrogen bond of the type N—H?N. These base pairs are again hydrogen bonded to their translated pairs in the direction of a cell diagonal. 相似文献
12.
Kevin A. Bunten David H. Farrar Alan J. Lough 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e267-e267
The title compound, BINAP oxide, C44H32O2P2, (I), was synthesized by direct oxidation of (R)‐(+)‐2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl (BINAP) with tert‐butyl hydroperoxide in toluene solution. The angle between the naphthyl planes of the binaphthyl group is 94.17 (3)°. 相似文献
13.
Smriti Khera Michael D. Carducci Jian‐Qiao Gu Barbara N. Timmermann 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o773-o775
The structure of an iridolactone isolated from Valeriana laxiflora was established as (4R,4aR,6S,7S,7aS)‐6‐hydroxy‐7‐hydroxymethyl‐4‐methylperhydrocyclopenta[c]pyran‐1‐one chloroform solvate, C10H16O4·CHCl3. The two rings are cis‐fused. The δ‐lactone ring adopts a slightly twisted half‐chair conformation with approximate planarity of the lactone group and the cyclopentane ring adopts an envelope conformation. The hydroxy group, the hydroxymethyl group and the methyl group all have β orientations. The absolute configuration was determined using anomalous dispersion data enhanced by the adventitious inclusion of a chloroform solvent molecule. Hydrogen bonding, crystal packing and ring conformations are discussed in detail. 相似文献
14.
John N. Low Justo Cobo Celeste Garcìa Manuel Melguizo Manuel Nogueras Adolfo Snchez Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):597-599
In the title compound, C10H9N3O5, which was formed by the reaction of 6‐amino‐2‐methoxy‐4(3H)‐pyrimidinone with dimethyl acetylenedicarboxylate, the molecules are linked by N—H?O hydrogen bonds [N?O 2.8974 (15) and 3.0300 (15) Å, and N—H?O 165 and 174°] into planar sheets built from alternating R22(8) and R66(42) rings. 相似文献
15.
Roger E. Gerkin 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):848-849
The title compound, C12H15NO, crystallized in the centrosymmetric space group C2/c with one molecule as the asymmetric unit. There is a single conventional N—H?O hydrogen bond, with a donor–acceptor distance of 2.912 (1) Å, which forms an R(8) cyclic dimer about a center of symmetry. There is a single significant intermolecular C—H?O interaction, which also forms an R(8) cyclic dimer about a center of symmetry. Taken together, these interactions form chains propagating along [110]. Structural comparisons are made with another β‐lactam, (1′R*,3R*,4S*)‐3‐(1′‐hydroxyethyl)‐4‐phenylazetidin‐2‐one. 相似文献
16.
Tamami Koshiyama Masako Kato 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):m446-m449
The title PtII complexes, viz. (2,2′‐bipyridine‐κ2N,N′)[(1R,2R)‐1,2‐diaminocyclohexane‐κ2N,N′]platinum(II) bis(hexafluorophosphate), [Pt(C6H14N2)(C10H8N2)](PF6)2, and [(1R,2R)‐1,2‐diaminocyclohexane‐κ2N,N′](1,10‐phenanthroline‐κ2N,N′)platinum(II) bis(hexafluorophosphate), [Pt(C6H14N2)(C12H8N2)](PF6)2, containing an aromatic α‐diimine and a non‐planar diaminocyclohexane, both form a ladder‐type structure, which is constructed via loose π–π stacking on the α‐diimine ligands and hydrogen bonding between the cyclic amines and the counter‐anions. In the former compound, there are two independent complex cations, both of which have a twofold axis through the Pt atom. 相似文献
17.
Jaime Vzquez Sylvain Berns Ruth Melndrez Roberto Portillo Ren Gutirrez 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):m424-m427
The title compounds, trans‐dichlorobis[(1R,2R,3R,5S)‐(−)‐2,6,6‐trimethylbicyclo[3.1.1]heptan‐3‐amine]palladium(II), [PdCl2(C10H19N)2], and trans‐dichlorobis[(1S,2S,3S,5R)‐(+)‐2,6,6‐trimethylbicyclo[3.1.1]heptan‐3‐amine]palladium(II) hemihydrate, [PdCl2(C10H19N)2]·0.5H2O, present different arrangements of the amine ligands coordinated to PdII, viz. antiperiplanar in the former case and (−)anticlinal in the latter. The hemihydrate is an inclusion compound, with a Pd coordination complex and disordered water molecules residing on crystallographic twofold axes. The crystal structure for the hemihydrate includes a short Pd⋯Pd separation of 3.4133 (13) Å. 相似文献
18.
Chune Dong Junlong Zhang Liangfu Zhang Zuolong Yu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):e21-e21
The crystal structure of the new chiral complex (1R,2R)‐1,2‐diphenyl‐1,2‐bis(8‐quinolinesulfonylamino)‐ ethylenediamine–acetone (1/1), C32H26N4O4S2.C3H6O, is reported. The conformation of the C32H26N4O4S2 (BQSDA) molecule is determined by a bifurcated N—H?N hydrogen‐bond system. The acetone of solvation is linked to the BQSDA molecule by an N—H?O hydrogen bond. 相似文献
19.
Dmitrii S. Yufit Judith A. K. Howard 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o141-o143
The crystal structures of (1R,1′S)‐2′,2′‐dichloro‐N‐(1‐phenylethyl)cyclopropane‐1′‐carboxamide, C12H13Cl2NO, (I), and (1R,1′R)‐2′,2′‐difluoro‐N‐(1‐phenylethyl)cyclopropane‐1′‐carboxamide, C12H13F2NO, (II), have been determined. Both crystals contain two independent molecules with different conformations of the phenylethyl groups. In the crystals of both compounds, the molecules are linked together by N—H⃛O hydrogen bonds, thus forming chains in the a direction. 相似文献
20.
Claude Didierjean Julien Marin Emmanuel Wenger Jean‐Paul Briand Andr Aubry Gilles Guichard 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o200-o203
X‐ray studies reveal that tert‐butyl (6S)‐6‐isobutyl‐2,4‐dioxopiperidine‐1‐carboxylate occurs in the 4‐enol form, viz. tert‐butyl (6S)‐4‐hydroxy‐6‐isobutyl‐2‐oxo‐1,2,5,6‐tetrahydropyridine‐1‐carboxylate, C14H23NO4, when crystals are grown from a mixture of dichloromethane and pentane, and has an axial orientation of the isobutyl side chain at the 6‐position of the piperidine ring. Reduction of the keto functionality leads predominantly to the corresponding β‐hydroxylated δ‐lactam, tert‐butyl (4R,6S)‐4‐hydroxy‐6‐isobutyl‐2‐oxopiperidine‐1‐carboxylate, C14H25NO4, with a cis configuration of the 4‐hydroxy and 6‐isobutyl groups. The two compounds show similar molecular packing driven by strong O—H⋯O=C hydrogen bonds, leading to infinite chains in the crystal structure. 相似文献