Crystal structure of β-D-acetyl cellobiose, C28H38O19

1976 ◽  
Vol 54 (9) ◽  
pp. 1365-1371 ◽  
Author(s):  
F. Leung ◽  
H. D. Chanzy ◽  
S. Perez ◽  
R. H. Marchessault
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Molecular Conformation ◽  
Direct Method ◽  
Crystal Data ◽  
Torsion Angles ◽  
Maximum Extension ◽  
X Ray ◽  
X Ray Crystallography ◽  
R Value

The crystal structure of β-D-acetyl cellobiose was studied by X-ray crystallography. The crystal data are a = 31.814(4), b = 19.414(5), c = 5.614(1) Å, space group P212121, Z = 4. The structure, solved by direct method, was refined by block-diagonal least-squares to a final R value of 0.075 for 2605 observed reflections. The molecular conformation involves 4C1 pyranose rings with glycosidic torsion angles corresponding to near maximum extension of the molecule. Substantial differences in conformational angles were observed between this molecule and the unacetylated counterpart. The molecules lie along the a-axis of the unit cell.

7α-Acetoxydihydronomilin: isolation, spectra, and crystal structure

1978 ◽  
Vol 56 (7) ◽  
pp. 1020-1025 ◽  
Author(s):  
Farid R. Ahmed ◽  
Angs Ng ◽  
Alex G. Fallis
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Least Squares ◽  
Furan Ring ◽  
Lactone Ring ◽  
Direct Method ◽  
Membered Ring ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray ◽  
Twist Boat

Methanol extraction of the ground seeds of Uncaria Gambier Roxb. followed by chromatography afforded a crystalline C30H38O10 terpene. This has been shown by X-ray analysis to be 7α-acetoxydihydronomilin. The crystals are orthorhombic, P212121, a = 13.158(2), b = 17.092(2), c = 12.689(2) Å, Z = 4, dx = 1.300, do = 1.300 g cm−3. The structure has been determined by the direct method and Fourier syntheses, and refined by block-diagonal least-squares to R = 0.042 for 2621 observed reflexions. The molecule contains a seven-membered lactone ring A, three six-membered rings B, C, D, a three-membered ring E, a furan ring F, and two acetate groups. A and B are chair, C is twist-boat, D is 1,3-diplanar, while E and F are planar. The A/B, A/C, C/D junctions are trans, D/E is cis, and F is linked to D by an equatorial C—C bond. The two acetate groups are in axial positions on A and B and are cis to each other. The O atom forming the apex of the three-membered ring is wedged between two H atoms and their parent C atoms at short intramolecular distances O … H = 2.28(2) and 2.28(3), and O … C = 2.623(3) and 2.668(4) Å. No intermolecular hydrogen bonding is indicated.

New Inclusion Compounds of Selenourea with Tetraethyl- and Tetra-n-propylammonium Halides

1997 ◽  
Vol 53 (2) ◽  
pp. 262-271 ◽  
Author(s):  
Q. Li ◽  
T. C. W. Mak
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Crystal Data ◽  
Tetraethylammonium Chloride ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
Dimensional Network ◽  
Single Column

Air-sensitive selenourea inclusion complexes tetraethylammonium chloride–selenourea (1/2), (C2H5)4N+.C1−.2[(NH2)2CSe] (1), tetra-n-propyl-ammonium chloride–selenourea (1/3), (n-C3H7)4N+.C1−.3[(NH2)2CSe] (2), tetra-n-propylammonium bromide–selenourea (1/3), (n-C3H7)4N+.Br−.3[(NH2)2CSe] (3), and tetra-n-propylammonium iodide–selenourea (1/1), (n-C3H7)4N+.I−.(NH2)2CSe (4), have been prepared and characterized by X-ray crystallography. Crystal data, Mo Kα radiation: (1), space group P21/n, Z = 4, a = 8.768 (5), b = 11.036 (6), c = 19.79 (1) Å, β = 96.92 (1)°, R F = 0.055 for 1468 observed data; (2), space group Cc, Z = 4, a = 18.091 (4), b = 13.719 (3), c = 11.539 (2) Å, β = 111.93 (3)°, R F = 0.051 for 1187 observed data; (3), space group Cc, Z = 4, a = 18.309  (4), b = 13.807 (3), c = 11.577 (2) Å, β = 112.45 (3)°, R F = 0.049 for 1592 observed data; (4), space group P21/n, Z = 4, a = 8.976 (1), b = 14.455 (2), c = 15.377 (3) Å, β = 94.16(1)°, R F = 0.062 for 1984 observed data. In the crystal structure of (1) the parallel alternate arrangement of selenourea–chloride ribbons and selenourea chains generates a puckered layer and the cations are sandwiched between them. In the isomorphous complexes (2) and (3) wide selenourea–halide double ribbons are crosslinked by bridging selenourea molecules via N—H...Se and N—H...X hydrogen bonds [average N...Se = 3.521 (8) and 3.527 (7), N...Cl = 3.354 (8) and N...Br = 3.500 (7) Å in (2) and (3), respectively] to form a channel-like three-dimensional network and the cations are accommodated in a single column within each channel. In the crystal structure of (4) the selenourea molecules are joined in the shoulder-to-shoulder fashion via N—H...Se hydrogen bonds [N...Se = 3.529 (7) and 3.534 (7) Å] to generate a ribbon and each selenourea molecule also forms a pair of chelating N—H...I hydrogen bonds [N...I = 3.567 (7) and 3.652 (7) Å] to an adjacent iodide ion.

Preparation and X-ray crystal structure of (4bα,6β,9β,9aα,10α,13α)-4b,5,6,7,8,9,9a,10,11,12,13,14-dodecahydro-4b-phenyl-6,9:10,13-dimethanodicyclohepta[a,c]naphthalene

1980 ◽  
Vol 58 (17) ◽  
pp. 1847-1850 ◽  
Author(s):  
Alan Richard Harris ◽  
Keith Mills ◽  
Michael Martin-Smith ◽  
Peter Murray-Rust ◽  
Judith Murray-Rust
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
The Novel ◽  
Oxidative Dimerization ◽  
Full Matrix ◽  
X Ray ◽  
X Ray Crystallography

The novel hexacyclic title hydrocarbon, formed by an unusual oxidative dimerization of 3-phenylbicyclo[3,2,1]oct-2-ene, has been isolated and its structure elucidated by means of X-ray crystallography. The trivial name 4b-phenylmariontetraene is proposed for the hydrocarbon. Crystals are orthorhombic, Pbca; a = 21.87(2), b = 10.57(2), c = 17.41(2) Å from diffractometer measurements (Mo [Formula: see text] radiation). V = 4024.2 Å3, Z = 8, Dc = 1.21 Mg m−3, F(000) = 1584, μ = 0.34 cm−3. The structure was solved by direct phasing methods with MULTAN 78 and was refined by weighted full-matrix least-squares procedures to R = 0.046 for 2287 observed reflexions.

Crystal structure of Bis(O-ethylxanthato)-1,10-phenanthrolinecadmium(II)

1976 ◽  
Vol 29 (4) ◽  
pp. 739 ◽  
Author(s):  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Title Compound ◽  
Crystallographic Axis ◽  
Full Matrix ◽  
X Ray ◽  
X Ray Crystallography ◽  
Phenanthroline Ligand

The crystal structure of the title compound, [Cd(C12H8N2)(CS2OEt)2], has been determined by X-ray crystallography using diffractometer data at 295 K and refined by full matrix least squares to a residual of 0.06 for 1350 'observed' reflections. Crystals are orthorhombic, P bcn, a = 14.870(4), b = 14.549(8), c = 10.249(1) �, Z = 4. The molecule lies on a twofold crystallographic axis; the phenanthroline ligand is symmetrically bidentate [Cd-N, 2.386(8) �], while the ethylxanthateligand is somewhat asymmetric [Cd-S, 2.647(3), 2.727(3)4 with a correspondingly asymmetric C-S geometry [C-S, 1.72(1), 1.66(1) �].

Crystal structure of Iodobis(1,10-phenanthroline)copper(II) iodide octasulphur

1977 ◽  
Vol 30 (9) ◽  
pp. 1965 ◽  
Author(s):  
TW Hambley ◽  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Title Compound ◽  
Significant Interaction ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Trigonal Bipyramidal ◽  
Pass Through

The crystal structure of the title compound, [Cu(C12H8N2)2I]I,S8, has been determined by X-ray diffraction at 295(1) K and refined by least squares to R 0.066 (2031 ?observed? reflections). ��� Crystal data: orthorhombic, Pbcb, a 7.984(5), b 16.690(4), c 22.986(12) Ǻ, Z 4. ��� The structure comprises five-coordinate trigonal bipyramidal [Cu(phen)2I]+ cations (I equatorial) lying on the 2 axes parallel to a which pass through the Cu-I bonds, together with iodide anions, and lattice S8 molecules, also lying on 2 axes but parallel to b. In the cation, Cu-I is 2.672(3), Cu-N (equatorial) 2.10(1) and Cu-N (axial) 2.00(1) Ǻ. S-S ranges from 2.004(7) to 2.059(7). There appears to be no significant interaction between the octasulphur molecules and any other species.

scholarly journals Synthesis, X-ray crystal structure, Hirshfeld surface analysis, and molecular docking studies of DMSO/H2O solvate of 5-chlorospiro[indoline-3,7'-pyrano[3,2-c:5,6-c']dichromene]-2,6',8'-trione

2021 ◽  
Vol 12 (4) ◽  
pp. 382-388
Author(s):  
Varun Sharma ◽  
Bubun Banerjee ◽  
Aditi Sharma ◽  
Vivek Kumar Gupta
Keyword(s):  
Crystal Structure ◽  
Molecular Docking ◽  
Direct Method ◽  
Docking Studies ◽  
One Pot ◽  
X Ray ◽  
Molecular Docking Studies ◽  
X Ray Crystallography ◽  
Three Component Reaction ◽  
Inhibition Property

The title compound, 5-chlorospiro[indoline-3,7'-pyrano[3,2-c:5,6-c']dichromene]-2,6',8'-trione was synthesized via one-pot pseudo three-component reaction between one equivalent of 5-chloroisatin and two equivalents of 4-hydroxycoumarin using mandelic acid as catalyst in aqueous ethanol at 110 °C. The synthesized compound was characterized by FT-IR, 1H NMR, and HRMS techniques. Single crystals were grown for crystal structure determination by using single X-ray crystallography technique. It was found that the crystals are triclinic with space group P-1 and Z = 1. The crystal structure was solved by direct method and refined by full-matrix least-squares procedures to a final R-value of 0.0688 for 6738 observed reflections. The crystal structure was stabilized by elaborate system of O-H···O, N-H···O, and C-H···O interactions with the formation of supramolecular structures. 3D Hirshfeld surfaces and allied 2D fingerprint plots were analyzed for molecular interactions. Molecular docking studies have been performed to get insights into the inhibition property of this molecule for Human topoisomerase IIα.

Crystal Structure of Tetraethylammonium Bromopentacarbonyltungstate(0)

1995 ◽  
Vol 48 (5) ◽  
pp. 1045 ◽  
Author(s):  
T Whyte ◽  
GA Williams
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
X Ray Diffraction ◽  
Full Matrix ◽  
Space Group ◽  
X Ray ◽  
Bond Lengths ◽  
R Value

The crystal structure of tetraethylammonium bromopentacarbonyltungstate (0), [NEt4] [W(CO)5Br], has been determined by single-crystal X-ray diffraction methods at 22�1°C. Crystals are tetragonal, space group P4/n, with a 9.206(2), c 10.484(2) Ǻ, and Z 2. Full-matrix least-squares refinement gave a final R value of 0.034 for 820 independent reflections. The [W(CO)5Br]- anion possesses exact C4v symmetry, with bond lengths W-Br 2.736(1), W-COtrans 1.93(1) and W-COcis 2.034(6) Ǻ.

Nitridomolybdenum Complexes of Tris(3,5-dimethylpyrazol-1-yl)Hydroborate and the X-Ray Crystal-Structure of {HB(3,5-Me2C3N2H)3)MoN(N3)2

1990 ◽  
Vol 43 (8) ◽  
pp. 1347 ◽  
Author(s):  
CG Young ◽  
F Janos ◽  
MA Bruck ◽  
PA Wexler ◽  
JH Enemark
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Least Squares ◽  
Elemental Analysis ◽  
Bond Distance ◽  
Octahedral Complex ◽  
Fourier Methods ◽  
X Ray ◽  
Distorted Octahedral ◽  
R Value

The reaction of (NEt4)2[MoNCl5] and K{HB(Me2pz)3}[HB(Me2pz)3- = tris (3,5- dimethylpyrazol-1-yl) hydroborate anion] produces both purple, diamagnetic {HB(Me2pz)3}MoNCl2 (1) and yellow, paramagnetic Net4 [{HB(Me2pz)3}MoNCl2] (2) (e.s.r.: {g} 1.961, {a}(95Mo) 57×10-4 cm-1), which have been separately isolated under different conditions. In contrast, the reaction of [ MoN (N3)4]- with Na{HB(Me2pz)3} results in the exclusive formation of red {HB(Me2pz)3} MoN (N3)2 (3). Crystals of (3) are monoclinic and belong to space group P21/n with a 16.440(2), b 8.787(2), c 16.754(2) Ǻ,β 112.47(1)°, V 2236.4 Ǻ3, and Z 4. The structure was solved by Patterson and Fourier methods, followed by least-squares refinement, using 3208 reflections, to a conventional R value of 0.032 ( Rw 0.047). In the distorted octahedral complex the molybdenum(VI) atom is coordinated by a facial HB(Me2pz)3- ligand , a terminal nitrido ligand with a Mo-N bond distance of 1.646(4)Ǻ, and two azide ligands. All complexes have been characterized by elemental analysis, infrared, 1H n.m.r. or e.s.r. spectroscopy, and mass spectrometry. Improved syntheses for the starting materials (NEt4)2 [MoNCl5] and (NEt4)2 [MoNCl4] are also reported.

Crystal Structure of an Ammonium Dithiocyanatocuprate(I) Complex with 18-Crown-6, [NH4(18-Crown-6){Cu(NCS)2}] Obtained from Zero Valent Metal

1997 ◽  
Vol 52 (11) ◽  
pp. 1311-1314 ◽  
Author(s):  
Julia A. Manskaya ◽  
Volodimir N. Kokozay ◽  
Konstantin V. Domasevitch
Keyword(s):  
Crystal Structure ◽  
Direct Method ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
One Dimensional ◽  
X Ray ◽  
X Ray Crystallography ◽  
A Direct Method

The new macrocyclic dithiocyanatocuprate(I) complex [NH4(18-crown-6){Cu(NCS)2}] has been prepared using a direct method of interaction and characterized by X-ray crystallography (orthorhombic, space group Cmc21, with a = 12.453(2), b = 21.650(4), c = 8.151(2) Å, V = 2197.6(8) Å3, Z = 4 , R1 (F) = 0.054; wR2(F2) = 0.141 for 972 unique reflections with I > 2σ(I) and R1(F) = 0.082; w/?2(F2) = 0.210 for all 1098 unique reflections). The lattice comprises complex cations [NH4(18-crown-6)]+ and infinite polymeric anions [Cu(NCS)2]- of a one-dimensional zig-zag structure. The copper atoms adopt three-fold coordination [CuN2S] (Cu-N 1,89( 1), 1,90( 1) Å; Cu-S 2.278(4) Å).

Crystal structure of Hydroxyimino(N,N'-dimethyl)malonamide

1977 ◽  
Vol 30 (9) ◽  
pp. 1929 ◽  
Author(s):  
SR Hall ◽  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Title Compound ◽  
Direct Methods ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Independent Molecules

The crystal structure of the title compound, namely hydroxyimino(N,N?- dimethyl)malonamide (MeNHCOC(=NOH)CONHMe), has been determined by single-crystal X-ray diffraction with diffractometer data at 295 K. The structure was solved by direct methods and refined by least squares to a residual of 0.055 for 1477 observed reflections. ��� Crystal data: monoclinic, P21/n, a 15.508(3), b 10.544(2), c 9.377(1) Ǻ, β 103.15(2)�, Z 8. ��� The two crystallographically independent molecules exhibit little conjugation throughout the C-C-C skeleton (<C-C> 1.50 Ǻ), the molecule being non-planar. <C=O> is 1.234, <N-CH3> 1.443, <OC-N> 1.323, <C-NO> 1.278 and (N-O) 1.375 Ǻ. The geometry is compared with those observed for several related derivatives.

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