Regioselective Benzoylation of Glycopyranosides by Benzoyl Chloride in the Presence of MoO2(acac)2
摘要:
Benzoylation of methyl and benzyl glycopyranosides by benzoyl chloride in the presence of MoO2(acac)(2) as a catalyst resulted in 3-benzoates with good yield and high regioselectivity. Simple synthesis of the monobenzoates of some glycopyranosides is suggested.
Regioselective benzoylation of glycopyranosides by benzoic anhydride in the presence of Cu(CF3COO)2
作者:Evgeny V. Evtushenko
DOI:10.1016/j.carres.2012.06.020
日期:2012.10
Benzoylation of methyl and benzyl glycopyranosides by benzoic anhydride in acetonitrile in the presence of copper(II) trifluoroacetate as a promoter has given monobenzoates with a good yield and high regioselectivity. The composition of monobenzoates depended both on a configuration of hydroxyl groups and on a configuration of aglycone. The simple syntheses of the monobenzoates of some glycosides are
Conformational equilibria of methyl α-<scp>L</scp>-arabinopyranosides in solution
作者:Rosa Lanzetta、Michelangelo Parrilli、Carmine Garzillo、Andrea di Matteo、Giuseppe del Re
DOI:10.1039/p29960000505
日期:——
except in the case of 2-substituted derivatives in CDCl3. The experimental data and a theoretical analysis aimed at explaining them in terms of intramolecular and stereoelectronic solvent effects are presented. It appears that certain electrostatic interactions and the anomeric effect, which favour 1C4 in conformational equilibria are particularly important in 2-substituted derivatives provided no
对CDCl 3中的甲基α- L-阿拉伯吡喃糖苷,吡啶和二恶烷进行的NMR实验研究表明,除了CDCl 3中有2个取代的衍生物外,构象异构体之间的平衡也朝着4 C 1构象异构体转移。提出了实验数据和旨在从分子内和立体电子溶剂效应方面解释它们的理论分析。看来,某些静电相互作用和端基异构作用有利于1 C 4。如果不破坏分子内H-桥,则构象平衡中的构象平衡在2-取代的衍生物中特别重要。这解释了实验结果,并进一步阐明了决定溶液中构象平衡的效应之间的相互作用。