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Extraction and Crystal Structure of β-Sitosterol 被引量:2
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作者 吴晓毅 巢志茂 +2 位作者 王淳 孙文 张贵峰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期801-806,共6页
The title compound β-sitosterol(C29H50O), an active phytosterol in many medicinal and edible plants, was characterized by X-ray diffraction analysis and extensive nuclear magnetic resonance(NMR) data. It crystall... The title compound β-sitosterol(C29H50O), an active phytosterol in many medicinal and edible plants, was characterized by X-ray diffraction analysis and extensive nuclear magnetic resonance(NMR) data. It crystallizes in monoclinic system, space group P21 with C29H50O·1/2H2O, a = 9.4226(7), b = 7.4824(9), c = 36.889(3) , V = 2597.0(4) 3, Z = 4, Dx = 1.084 g/cm3, Mr = 423.70, F(000) = 948, and μ = 0.064 mm-1. The final R = 0.0886 and wR = 0.2234 for 10157 observed reflections(I 〉 2σ(I)). The molecular crystal structure of β-sitosterol shows relative stereochemistry of 24R-ethylcholest-5-en-3β-ol. The molecule is composed of one steroid nucleus(3 six-membered rings and 1 five-membered ring) and one sidechain of 10 carbons. There are two C29H50O molecules and one H2O molecule in a symmetrical unit, and the title compound is stacked into a special laminated structure through hydrogen bonds and van der Waal forces. The special laminated structure was first reported. 展开更多
关键词 β-sitosterol crystal structure nmr x-ray diffraction laminated structure
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Extraction and Absolute Crystal Structure of Stachyose 被引量:5
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作者 吴晓毅 巢志茂 +1 位作者 王淳 孙文 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第1期65-70,共6页
The title compound stachyose (C24H42021), a biologicaly active tetrasaccharide, was characterized by X-ray diffraction analysis. It crystallizes in the orthorhombic system, space group P21212 with C24H42021, a = 23.... The title compound stachyose (C24H42021), a biologicaly active tetrasaccharide, was characterized by X-ray diffraction analysis. It crystallizes in the orthorhombic system, space group P21212 with C24H42021, a = 23.8760(3), b = 12.71028(I2), c = 10.81279(11) A, V = 3281.36(6) A3, Z = 4, Dc= 1.511 g/cm3, Mr = 746.58, F(000) = 1576, and μ = 1.230 mm^-1. The final R = 0.0666 and wR = 0.1797 for 6298 observed reflections (I 〉 2σ(I)). The molecular crystal structure of stachyose shows absolute stereochemistry of fl-D-fructofuranosyl a-D-galactopyranosyl- (1→6)-a-D-galactopyranosyl-(1→6)-a-D-glucopyranoside. The molecule is composed of two a-D-galactoses, one a-D-glucose, and one r-D-fructose and sequentially linked as a-Gal (1 →6) a-Gal (1→6) a-Glc (1→2) fl-Fru. The title compound is stacked into a 3D layer structure through hydrogen bonds. NMR spectra data are also assigned. In the crystal packing, X-ray analysis indicates that there are two intramolecular and eleven intermolecular hydrogen bonds in this compound. 展开更多
关键词 STACHYOSE crystal structure TETRASACCHARIDE nmr x-ray diffraction
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Zirconium-mediated Synthesis and Crystal Structure of 3,6-Diiodo-4,5-dialkyl-phthalic Acid Dimethyl Ester 被引量:1
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作者 李旭东 王会 +2 位作者 李君秋 门奕灿 曲红梅 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1347-1356,共10页
A novel series of para-diiodobenzene derivatives, 3,6-diiodo-4,5-dialkyl-phthalic acid dimethyl esters, were prepared via cycloaddition of two TMS-substituted alkynes and dimethyl acetylenedicarboxylate, which was med... A novel series of para-diiodobenzene derivatives, 3,6-diiodo-4,5-dialkyl-phthalic acid dimethyl esters, were prepared via cycloaddition of two TMS-substituted alkynes and dimethyl acetylenedicarboxylate, which was mediated by zirconocene. After iodination, three new compounds of 3,6-diiodo-4,5-dimethyl(dipropyl, dibutyl)-phthalic acid dimethyl esters (3a, 3b, 3c) were synthesized in high region-selectivity and yields, and characterized by NMR. The crystal structures were determined by single-crystal X-ray diffraction. The crystal of 3a (C12H121204, Mr = 474.02) belongs to the triclinic system, space group Pi with a = 7.6238(10), b = 9.4571(12), c = 10.8221(14) A, a = 66.611(10), fl = 88.511(12), 7 : 77.604(11)% V= 697.93(16) A3, Z= 2, F(000) = 444, Dc = 2.256 mg/m3, g = 4.509 mm-1, T=133(2) K, S = 1.014, R = 0.0229 and wR = 0.0547 for 2644 observed reflections with I 〉 20(/); the crystal of 3b (C16H201204, Mr - 530.12) is of triclinic system, space group Pi with a = 9.4122(19), b = 10.626(2), c = 11.353(2) A, a = 97.90(3), fl = 113.83(3), y = 110.22(3)°, V= 922.6(3) A3, Z- 2, F(000) = 508, Dc - 1.908 mg/m3, g = 3.422 mm-1, T = 113(2) K, S = 1.115, R = 0.0428 and wR = 0.1072 for 3971 observed reflections with I〉 20(/); the crystal of 3c (ClsH241204, Mr = 558.17) belongs to the monoclinic system, space group P21/c with a = 26.396(2), b = 8.7560(8), c = 25.7970(18) A, fl = 91.721(4)o, V= 5959.6(8) A3, Z = 12, F(000) = 3240, Dc = 1.866 mg/m3,/z = 3.184 mm-l, T= 113(2) K, S = 1.154, R = 0.0424 and wR = 0.0766 for 13056 observed reflections with I 〉 20(/). 展开更多
关键词 ZIRCONOCENE 3 6-diiodo-4 5-dialkyl-phthalic acid dimethyl ester para-diiodobenzene derivative crystal structure x-ray diffraction nmr
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Crystal and Molecular Structure of 4-Benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonitrile
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作者 E.Korkusuz E.Sahin I.Yildirim 《Crystal Structure Theory and Applications》 2012年第1期1-8,共8页
The crystal structure of potential active 4-benzoyl-1,5-diphenyl-1H*-pyrazole-3-carbonitrile (C23H15N3O) (I) has been determined from single crystal X-ray diffraction data. Also IR, Uv-vis and NMR spectral data were d... The crystal structure of potential active 4-benzoyl-1,5-diphenyl-1H*-pyrazole-3-carbonitrile (C23H15N3O) (I) has been determined from single crystal X-ray diffraction data. Also IR, Uv-vis and NMR spectral data were determined. The title compound crystallizes in the monoclinic space group P* 21/c, with a* = 9.3167(2), b* = 20.6677(3), c* = 10.6143(3) ?, β* = 112.665(3)°, V* = 1886.00(8) ?3, Dcalc* = 1.23g cm-3, Z* = 4. In the structure, intermolecular H*-bonds lead to the formation of a centrosymmetric dimmer of the molecule. Furthermore, the compound has a wide transmission window (300 to 1100 nm) with a transparency of nearly 100% and the UV cut-off wavelength occurs at 242 nm. 展开更多
关键词 Pyrazole-3-Carbonitrile 2 3-Furandione Single crystal structure x-ray diffraction IR nmr Spectra
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