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1.
The crystal structure of the title compound (C27H44NO2Cl) is determined by X-ray structure analysis. The compound crystallizes in the orthorhombic space group P212121 with the unit cell parameters a = 7.207(1) Å, b = 11.292(1) Å, and c = 32.373(5) Å. The structure is solved by direct methods and refined to R = 0.060. Rings A and C exist in the chair conformation. Ring B adopts a half-chair conformation, and ring D is a 13β envelope. The A/B ring junction is quasi-trans, while the B/C and C/D ring systems are trans fused about the C(8)–C(9) and C(13)–C(14) bonds, respectively. Molecules are linked together by the C-H?O hydrogen bonds. 相似文献
2.
V. G. Puranik N. N. Dhaneshwar S. S. Tavale J. B. Bhonsle 《Journal of chemical crystallography》1991,21(5):547-551
The structure of the title compound, a cyclic ether acetate lactone, has been established uniquely by X-ray crystallography. C16H24O4 is orthorhombic, space groupP212121, with the cell dimensionsa=7.524(2),b=10.686(2),c=19.472(2) Å,V=1565.6(4) Å3,Z=4,M
r=280.4,D
x=1.19 g cm–3,D
o=1.20 g cm–3,F(000)=608,T=293 K, finalR=0.050. The two cyclohexane ring junction iscis while the lactone ring junction istrans. Both the cyclohexane rings have the chair conformation and the -lactone ring has an envelope conformation with C(7) being at the tip of the flap. The acetoxy side chain is-equatorial. There is an intramolecular C-H---O interaction C(4)O(4)=2.666(4) Å.N. C. L. Communication No. 5064. 相似文献
3.
The crystal structure of the title compound (4,17(20)-trans-pregnadiene-3,16-dione, C21H28O2) has been determined by direct methods using single-crystal X-ray diffraction data. The compound crystallizes into the orthorhombic space group P212121 with the unit cell parameters a = 7.908(2) Å, b = 13.611(3) Å, c = 16.309(4) Å, and Z = 4. The structure has been refined to R = 0.058 for 3667 observed reflections. The bond distances and angles are in good agreement with guggulsterone E and other related steroid molecules. Ring A exists in the distorted sofa conformation, while rings B and C adopt the distorted chair conformation. Five-membered ring D is intermediate between the half-chair and envelope conformations. The A/B ring junction is quasi-trans, while ring systems B/C and C/D are trans fused about the C(8)–C(9) and C(13)–C(14) bonds, respectively. The steroid nucleus has a small twist, as shown by the C(19)–C(10)...C(13)–C(18) pseudo-torsion angle of 7.2°. The crystal structure is stabilized by intra-and intermolecular C-H...O hydrogen bonds. 相似文献
4.
Gabriele Bocelli Marie Florence Grenier-Loustalot 《Journal of chemical crystallography》1983,13(1):19-29
C26H38O4,Mr=414.6, is monoclinic,P21/c, witha=15.059(2),b=7.348(2),c=23.164(3) Å,β=90.35(16)°,V c =2563.13(85) Å3,D x =1.07(4) g cm?3,μ(CuKα)=5.28 cm?1. The structure was determined by direct methods and refined by full-matrix least squares toR=0.074 for 2479 observed reflections. The two cyclohexane rings both adopt a chair conformation. 相似文献
5.
13α-Hydroxy-α-isolupanine (I) and 13β-hydroxy-α-isolupanine (II) crystallize in the space groupP212121 witha=13.123(2),b=13.221(3),c=8.224(1) Å,Z=4 anda=9.745(2),b=11.383(1),c=12.710(2) Å,Z=4, respectively. Structural differences between the epimeric molecules are concentrated around ringA. In (I) ringA has a half-chair conformation, and in (II) it is a distorted sofa. TheA/B ring junction configuration isquasi-trans in the case of (I) andquasi-cis in (II). The above differences can be explained by the different intermolecular interactions observed in these two structures. 相似文献
6.
Rajnikant V. K. Gupta E. H. Khan S. Shafi S. Hashmi Shafiullah B. Varghese Dinesh 《Crystallography Reports》2001,46(6):963-966
The crystal structure of cholest-4-ene-3,6-dione (C27H44O2) has been determined by X-ray diffraction methods. The compound crystallizes in the monoclinic crystal system (space group P21) with the unit cell parameters a = 10.503(4) Å, b = 8.059(1) Å, c = 14.649(1) Å, β = 105.4(2)°, and Z = 2. The structure has been refined to an R value of 0.035 for 2252 observed reflections. Ring A of the steroid nucleus exists in a sofa conformation, while rings B and C adopt a chair conformation. The five-membered ring D exhibits a half-chair conformation. The molecules in the unit cell are linked together by the C-H?O hydrogen bonds. 相似文献
7.
Jesús Valdés-Martínez Manuel Rubio Raul Cetina Rosado Javier Salcedo-Loaiza Rubén A. Toscano Georgina Espinosa-Pérez Simón Hernandez-Ortega Klaus Ebert 《Journal of chemical crystallography》1997,27(11):627-634
The crystal structure of 5-methyl-acetophenonethiosemicarbazone monohydrate,A, and salicylaldehyde-2-methylthiosemicarbazone monohydrate,B, were determined using single crystal X-ray diffraction.A crystallizes in the monoclinic space groupC2/c, with lattice parametersa=14.161(2),b=15.753(1) Å,c=11.084(1) Å, β=112.59(1)° andZ=4, yielding a calculated density ofD calc=1.352 mg/m3.B crystallizes in the triclinic space groupP1, witha=7.233(2) Å,b=7.371(2) Å,c=11.841(2) Å, α=82.77(2)°, β=78.33(2)°, γ=63.06(2)° andD calc=1.371 mg/m3 forZ=2,. In bothA andB the immine nitrogen and the sulfur atom areanti with respect to N2-C8. WhileA presents the usual intramolecular six membered hydrogen bond ring,B has instead an intermolecular hydrogen bond between the hydroxy moiety of the salicyladehyde and a water molecule. AM1 calculations agree with the experimental conformations observed in both compounds. 相似文献
8.
Jan A. Kanters Johan Buitenhuis Jan Kroon Mohamed Mathlouthi Joop H. van der Maas Bert Lutz 《Journal of chemical crystallography》1990,20(1):1-8
C12H20O10,M r=324.28, orthorhombic,P212121,a=9.4476(8),b=10.2247(8),c=13.5827(11) Å,V=1312.07(18) Å3,Z=4,D x=1.642 g cm?3, MoKα radiation (λ=0.71073 Å)μ=1.4 cm?1,F(000)=688,T=295 K, finalR=0.041 for 1089 reflections withI≥2.5σa(I). The molecule consists of aβ-d-fructopyranose and a α-d-fructofuranose ring which are linked by a 1,4-dioxane ring. The pyranose ring and the dioxane ring both have a chair conformation, and the furanose ring has an envelope conformation. All six hydroxyl groups act as donors in intermolecular hydrogen bonding. Each molecule is hydrogen-bonded to eight neighbor molecules by fourteen hydrogen bonds, forming a three-dimensional framework. The hydrogen bonds of varying geometry give rise to five sharp hydroxyl stretch vibrations in the infrared spectrum. In diheterolevulosan IV the central dioxane ring is a boat. Molecular mechanics calculations on diheterolevulosan II and IV having different boat and chair conformations of the dioxane ring show that the lowest energy conformations correspond to the conformations observed in the crystal structure. For comparison the calculations also have been applied to 1,4-dioxane having boat and chair conformations. 相似文献
9.
The crystal structure of 3β-hydroxy-4-(1,4-oxazin-4-yl)-androstane (C31H54NO2) has been determined by X-ray crystallographic techniques. The compound crystallizes in the orthorhombic space group P21212 with the following unit-cell parameters: a = 7.124(1) Å, b = 10.127(1) Å, c = 40.660(1) Å, V = 2933.4(1) Å3, and Z = 4. The structure has been solved by direct methods and refined to an R factor of 0.067. Three six-membered rings, A, C, and E, exist in the chair conformation, while the ring B adopts a distorted half-chair conformation. The five-membered ring, D, has a distorted envelope conformation. The crystal structure is stabilized by strong intermolecular O-H...O hydrogen bonds. 相似文献
10.
Doyle Britton 《Journal of chemical crystallography》1997,27(7):405-412
Trichlorotricyanobenzene-mesitylene (1/1) is monoclinic, space group P21/n; at ?88°Ca=10.509(3),b=14.863(7),c=11.518(3) Å, β=99.38(2)0,V=1775(2) Å3,D x =1.409(2) g cm?3,Z=4. Trichlorotricyanobenzene-benzene (1/3) is hexagonal, space group $P\bar 6$ ; at ?99°Ca=17.3914(3),c=7.2673(1) Å,V=1903.6(1) Å3,D x =1.2844(1) g cm?3,Z=3. In both complexes there are stacks of alternating trichlorotricyanobenzene and hydrocarbon molecules. In both complexes there are sheets of molecules perpendicular to the stacks. In the mesitylene complex these sheets contain equal numbers of both kinds of molecules with the trichlorotricyanobenzene molecules arranged in tapes. In the benzene complex the sheets contain only one kind of molecule or the other. The sheets containing the trichlorotricyanobenzene molecules have approximately linear C?N...Cl?C intermolecular interactions with N...Cl distances about 3.02 å. 相似文献
11.
The crystal and molecular structures of the alkaloid Royline {(1α,6β,14α, 16β)-20-ethyl-4-hydroxymethyl)-1,6,14,16-tetramethoxyaconitane-7,8-diol} with a water molecule has been determined by X-ray diffraction analysis. The compound crystallizes in the space group P21 with the unit cell parameters a = 10.985(1) Å, b = 7.898(1) Å, c = 14.956(1) Å, β = 102.96(1)°, V = 1264.52 Å3, Z = 2, λMoK α = 0.71073 Å, and R = 0.033 for 2067 observed reflections. Rings A, B, and C adopt a chair conformation, ring D is a half-boat, ring E is a half-chair, and ring F is in an envelope conformation with C(14) at the flap. Molecules are linked together in the crystal by hydrogen bonds. 相似文献
12.
José Castañeda-Acosta Alfonso G. Ober Frank R. Fronczek Nikolaus H. Fischer Giacomo Chiari 《Journal of chemical crystallography》1997,27(11):641-644
The heliangolide-class sesquiterpene lactone 8β-angeloyloxy-9α-acetoxycalyculatolide, C22H26O8,1, crystallizes in orthorhombic space groupP212121 witha=12.455(3),b=12.601(3),c=14.023(5) Å,V=2200(1)Å,3 Z=4.R=0.059 for 1735 observed data. The 11,13-dihydro-11α, 13-epoxyatripliciolide-8β-angelate, C20H22O7. 1/2 H2O,2, crystallizes as the hemihydrate with two molecules in the asymmetric unit in triclinic space groupP1 witha=9.422(1),b=9.559(1),c=12.358(3) Å, α=101.62(2)°, β=91.30(2)°, γ=117.80(1)°,V=955.6(7)Å3,Z=2.R=0.046 for 3607 observed data. In both, the 10-membered rings adopt approximate chair-boat conformations. Their conformations are typical for heliangolides. The methyl group C14 is α, while the C-15 has a β-orientation. The α-methylene-γ-lactone istrans-fused at C6 and C7 with H6 β and H7 α. In compound2, the epoxide at C11–C13 has an α orientation. 相似文献
13.
The crystal and molecular structure of the title complex, C18H19N2O2Ni, has been determined by direct methods. The compound crystallizes in the monoclinic crystal system witha=22.973(1),b=5.212(1),c=27.076(1)Å, β=106.46(1)°, space groupC2/c,V=3109.1(6)Å3, Z=8, andD x=1.51g cm?3. The nickel atom is in a slightly distorted square-planar environment of two oxygens [Ni(1)?O(1) 1.824(3) and Ni(1)?O(2) 1.856(3)Å] and two nitrogens [Ni(1)?N(1) 1.849(3) and Ni(1)?N(2) 1.932(3)Å] with O?Ni?N angles between 85.7(1) and 97.1(1)°. The nickel atom is 0.006 Å out of the plane of its ligands. 相似文献
14.
erajni-kant-verma@hotmail.com Rajnikant V. K. Gupta Jamal Firoz Shafiullah R. Gupta 《Crystallography Reports》2000,45(5):785-788
The crystal and molecular structure of the steroid 5α-cholest-6-one has been determined by X-ray diffraction analysis. The compound crystallizes in space group P21 with the unit cell parameters a = 10.575(1) Å, b = 7.698(1) Å, c = 15.284(2) Å, β= 99.34(1)°, V = 1227.72 Å3, Z = 2, and R = 0.054 for 1634 observed reflections. The six-membered rings (A, B, and C) have the chair conformations, whereas the five-membered ring Dis intermediate between 13β-envelope and 13β-14α half-chair. All the rings of the steroid skeleton are trans connected. The molecules are linked together by the intermolecular C-H?O hydrogen bonds. 相似文献
15.
Debra J. Carroll Gretchen S. Mandel Neil S. Mandel Ph.D. 《Journal of chemical crystallography》1983,13(1):9-17
The title compound is C16H20O5, MW=292.3, orthorhombic,P212121,a=9.741(2),b=29.391(7),c=5.354(1) Å from diffractometer measurements,V=1532.8 Å3,Z=4,D c =1.267 g cm?3,D o =1.271 g cm?3 (ether/1,1,2,2-tetrabromoethane), λ(Mo Kα)=0.71069 Å,F(000)=624,μ=1.02 cm?1, crystal dimensions 0.23×0.23×0.40 mm,R=0.049 for 1164 observed reflections. The molecule contains a possibly significant asymmetric ether linkage between the oxacyclohexane ring and the highly anisotropic benzyl ring. The packing consists of zigzagged chains parallel to thea-axis formed by hydrogen bonds. The chains are separated by van der Waals contacts. 相似文献
16.
Crystals of C4H10NO2Cl, M r =139.58 are monoclinic,P21/c, witha=7.061(2),b=7.194(2),c=13.932(3) Å,β=98.88(2)°,V=699.2(5) Å3,Z=4,D x=1.326(1) g cm?3. The structure was solved by hand application of direct methods and refined to a goodness of fit of 1.7 for 1212 reflections and 114 parameters (R=0.028 for 1202 reflections withF 2>0). 相似文献
17.
José Castañeda-Acosta Howard G. Pentes Frank R. Fronczek Nikolaus H. Fischer 《Journal of chemical crystallography》1997,27(11):635-639
The germacrolide-class sesquiterpene lactone, 1,10-epoxyparthenolide, C15H20O4,1, crystallizes with two independent molecules in monoclinic space groupP21 witha=10.6845(5),b=9.0763(4),c=15.4326(7) Å, β=105.887(4)°,V=1439.4(3) Å3,Z=4.R=0.037 for 2425 observed data. Its 11βH, 13-dihydro-derivative 1,10-epoxydihydroparthenolide, C15H22O4,2, crystallizes in orthorhombic space groupP212121 witha=7.6414(10),b=12.559(2),c=14.6821(14) Å,V=1409.0(3) Å3 Z=4.R=0.031 for 1555 observed data. The corresponding unexposidized compound, 11βH,13-dihydrocostunolide, C15H22O2,3, crystallizes with three independent molecules in orthorhombic space groupP212121 witha=7.3576(5),b=23.505(3),c=24.185(2) Å,V=4182(1) Å3,Z=12.R=0.070 for 2767 observed data. In all, the 10-membered rings adopt approximate chair-chair conformations. In all, the double bonds or epoxidized double bonds are E, both methyl groups on the 10-ring are β, and the α-methylene-γ-lactone (or α-methyl-γ-lactone) istrans-fused at C6 and C7 with H6 β and H7 α. In the dihydro compounds, the H at C11 is β. 相似文献
18.
The molecular structure of cholest-3,5-diene-7-one (C27H42O) is determined by X-ray diffraction. The compound crystallizes in the orthorhombic crystal system (space group P212121) with unit cell parameters a = 11.281(5) Å, b = 11.350(5) Å, c= 18.518(5) Å, and Z = 4. The structure is solved by direct methods and refined to an R-value of 0.054 for 1070 observed reflections [Fo > 4σ(Fo)]. Ring A adopts a distorted half-chair conformation, ring B exists in sofa conformation, ring C acquires a chair conformation, and the five-membered ring D occurs in distorted half-chair conformation. The crystal structure is stabilized by van der Waals forces. 相似文献
19.
Andrzej Katrusiak Zygmunt Kałuski Paweł Pietrzak Jerzy Skolik 《Journal of chemical crystallography》1986,16(2):191-206
1(6)-Dehydrosparteinium monoperchlorate, [C15H25N2]+·ClO
4
–
, is orthorhombicP212121,a=12.473(2),b=24.292(3),c=10.835(1) Å,V
c
=3353.7(9) Å3,Z=8,D
x
=1.32,D
m
=1.32 g cm–3, (CuK)=20.7 cm–1. The finalR was 0.097 for 2091 observed counter reflections. A partial disorder of the crystal structure has been observed. The two independent perchlorate anions are orientationally disordered, and the peripheral atoms in the cation skeletons have large temperature factors due both to conformational disorder of ringsA and to disordered orientations of the whole cations alike. In ringsA, atoms C(3) and C(4), trans-annular to the immonium bond, are disordered to a different extent in each of the two independent cations. RingsB,C, andD have sofa (distorted towards half-chair), chair, and chair conformations, respectively. The quinolizidinium and quinolizidine moieties have planar and cis configurations, respectively. The title compound was obtained from 5-dehydrosparteine, the product of mercuric acetate dehydrogenation of sparteine at room temperature. From13C NMR measurements in2H2O and in DMSO-2H6 it is evident that, in solution, the molecular geometry with chair/chair cis-ring fusion within the quinolizidine moiety is present, as was found in the crystalline state by X-ray analysis. 相似文献
20.
Joe W. Vaughn 《Journal of chemical crystallography》1983,13(3):231-239
The results of an X-ray structure determination of one of the three possible chloride salts of [Cr(en) F2(OH2)2]+ show the two fluoro ligands to betrans to each other. The purple crystals are monoclinic in the space groupC2/c-C 2h 6 , witha=11.409(3),b=9.319(2),c=10.260(3) Å,β=128.73(2)° andD c =1.73 g cm?3 forZ=4. Least-squares refinement based on 1341 independent observed reflections resulted in a finalR of 0.026. The molecule lies on a crystallographic two-fold axis, and the Cr-F, Cr-N, and Cr-O bond lengths are 1.885(1), 2.044(2), and 1.997(2) Å respectively. It is suggested that the ill-defined shoulder in the visible electronic spectrum of this complex is indicative of atrans dihalo geometry. 相似文献