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PREPARATION AND STRUCTURE OF FIVE DERIVATIVES OF β-(1→3)-D-GLUCAN ISOLATED FROM PORIA COCOS SCLEROTIUM

Chinese Journal of Polymer Science 2004年第2期22卷 137-145页

作者：张俐娜 Department of Chemistry Wuhan University Wuhan 430072 China

A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insoluble β -(1—>3)-D-glucan, sample PCS3- isolated from fresh sclerotium of Poria cocos was sulfated in dimethyl sulfoxide (Me 2 SO), carboxymethylated in NaOH, isopropanol solution, as well as methylated, hydroxyethylated and hydroxypropylated in the new solvent system, respectively, to obtain five water-soluble derivatives coded as S-PCS3- C- PCS3- M-PCS3- HE-PCS3- and HP-PCS3- Their chemical structure and distribution of substitution were characterized by infrared spectroscopy (IR), elementary analysis (EA), 1 H-NMR, 13 C-NMR, 2D-COSY, 2D-TOCSY and 2D- 1 H-detected 1H 13C HMQC spectra. The results reveal that the relative reactivity of hydroxyl groups of the β -(1-?3)-D-glucan is in the order C-6 > C-4 > C-2 on the whole. The substitution of the samples S-PCS3- C-PCS3- and M-PCS3- occurred mainly at C-6 position and secondly at C-4 and C-2 positions, and that of HE-PCS3- occurred at C-6 and C-4 positions and of HP-PCS3- almost completely occurred at C-6 position. The degrees of substitution (DS) obtained from 13 C-NMR range from 0.23 to 1.27. The water solubility of the derivatives is in the order S-PCS3- >C-PCS3- >M-PCS3- >HE-PCS3- >HP-PCS3- This work provides a novel and nonpolluting process for the methylation, hydroxyethylation and hydroxypropylation of β -(1—>3)-D-glucan.

关键词： Chemical structure Sulfation Carboxymethylation Methylation hydroxyethylation Hydroxypropylation β-D- glucan Poria cocos sclerotium NMR

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Synthesis and Crystal Structure of 2-O-(2-hydroxyethyl)-D-glucose

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Chinese Journal of Structural Chemistry 2013年第4期32卷 515-520页

作者：傅颖侯红霞杨延寿何银霞朱文博 Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education Key laboratory Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal University

The title compound, 2-O-（2-hydroxyethyl）-D-glucose （CsH1607, Mr= 224.21）, has been synthesized and its structure was characterized by using NMR spectrum and X-ray single-crystal diffraction. This molecule crystallizes in the monoclinic system, space group P21, with a = 8.399（17）, b = 6.620（14）, c = 9.81（2） A, β = 115.110（17）°, V= 493.7（18） A3, Z = 2, Dc = 1.508 mg/m3,/1 = 0.13 mm-1, F（O00） = 240, the final R = 0.0464 and wR = 0. l 15 for 152 ] observed reflections （1 〉 2a（I））. X-ray crystal structure analysis revealed that the conformation of the pyranosyl ring existed in a slightly distorted act chair conformation （Cremer-Pople puckering parameters of Q = 0.573（4） A, 0 = 6.7（3）0 and = -5.2（2）°）. The molecule exists as a monomer in the solid state, whose conformation is stabilized via multiple inter- and intramolecular hydrogen bonds.

关键词： glucose hydroxyethylation crystal structure

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