| In this thesis, using of methyl 2-keto a-D-glucopyranoside in synthetic methodology was discussed. Through studying on the nucleophilc addition of anilines to methyl 2-keto a-D-glucopyranoside and the Henry reaction, some new methods have been developed to prepare 2-deoxy amino glycosides and branched-chain monosaccharides. Among the three novel reactions found in the research on anilines' addition to methyl 2-keto a-D-glucopyranoside, two ones were used for synthesis of two kinds of totally seventeen new compounds, including 2-arylamino-2-deoxy 3-keto glucopyranosides and indole derivatives with sugar unit. Then eleven D-allosamine derivatives were obtained by stereo-specific reduction of the 3-keto glycosides. Furthermore, based on the stereo-selective Henry reaction of methyl 2-keto a-D-glucopyranoside, methyl 2-nitromethyl-2-deoxy a-D-glucopyranoside which is an important branched sugar was prepared. The mail results obtained are as follows.1. A novel carbonyl transposition led by anilines' nucleophilic addition to methyl 2-keto a-D-glucopyranoside was discovered. And the mechanism of the reaction concerned to an enol rearrangment was provided through tracing the change of 'H-NMR and I3C-NMR of a hemiacetal intermediate which was obtained in the reaction of o-phenylene diamine with 2-keto glycoside. Both the intermediate and the converting product were identified by 'H-NMR, 13C-NMR, !H-'H COSY and HMQC. Making use of this reaction, thirteen methyl 2-arylamino-2-deoxy 3-keto glucopyranosides (5~17) with different substituted arylamino groups and twoR= p-OCH3(5), H(6), o-CH3(7), m-CH3(8),p-CH3 (9), 2, 4-Dimethyl (10), 2, 5-Dimethyl(Il), p-OH (12), o-CI (13), p-CI(14), p-F(15), p-Br(16), p-COOEt(17)pyrazine derivatives have been synthesized. And the 3-keto glycosides can be employed to asymmetric synthesis.2. Two other new reactions were found in studying the anilines' nucleophilic addition to methyl 2-keto cc-D-glucopyranoside. One was the carbonyl transpostional reaction accompanied with the demethoxyl process which happened when 2-keto glucoside interacted with benzocaine and 2,4-dichlor aniline. Two oxo glucals were obtained by this method. The other was the one-step reaction for the synthesis of indole derivatives containing sugar unit was achieved by two equivalents of strong nucleophic anilines" addition to 2-keto glucoside. The possible mechanism was provided as following. At first, one molecular aniline attacked to the 2-keto group leading to the transposition of carbonyl associated with demethoxyl reaction. Then the second molecular of aniline attacked the 3-keto group accompanied with intramolecular electrophilic substitution. Using this reaction, four indole derivatives (20~23) have been prepared. This reaction provides a method to synthesis of alkaloid from 2-keto glycoside.3. The stereospecific reduction of methyl 2-arylamino-2-deoxy 3-keto glucopyranoside has been also studied. When the 3-keto glycosides was reduced by sodium borohydride, the D-allo configuration was considered the most probable since it has an equatorial arylamino group at C-2 position and reduction of the keto group was considerably less hindered to equatorial attack by borohydride ion to give an axial hydroxyl, than axial attack by borohydride to give an equatorial hydroxyl. Eleven methyl 2-arylamino-2-deoxy a-D-allopyransides (36~46) were obtained as expected. And the configuration of the product was elucidated by the X-ray diffraction analysis. This reaction provides a new way to synthesis of D-allosamine?derivatives which is the candidate of new type of chitinase inhibitor. In consideration of that the substrate we used was the most abundant hexose, D-glucose, this synthesis was more convenient to the others reported.R = H (36); p-OCH3 (37); O-CH3 (38); m-CH3 (39); p-CH3 (40); 2,4-Dimethyl (41); 2,5-Dimethyl (42); o-Cl (43); p-Cl (44); p-F(45); p-Br(46)4. Methyl 2-nitromethyl-2-deoxy a-D-glucopyranoside (50) was stereo-selective synthesized by Yo...
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