2-取代的甲基α-d-吡喃半乳糖苷:对Griffonia simplicifolia I isolectins的A和B亚基的合成和结合亲和力
摘要:
N-乙酰基,N-三氟乙酰基,N-丙酰基,N-甲酰基,N-苯甲酰基,Np-硝基苯甲酰基,Np-氨基苯甲酰基和甲基-2-氨基-2-脱氧-α-甲基的N-甲基衍生物的结合亲和力已通过半乳甘露聚糖的半抗原抑制分析确定了D-半乳糖吡喃糖苷和Griffonia simplicifolia I isolectins的A和B亚基的甲基α-D-半乳糖吡喃糖苷的2-O-乙酰基,-苯甲酰基,-苄基和-甲基衍生物-isolectin沉淀系统。这些糖-蛋白质相互作用的模型与基于电子和空间效应的结果解释一起提供。
New results in the isopropylidenation of galactopyranosides. Useful intermediates for the synthesis of galactose derivatives.
作者:Pier Luigi Barili、Giancarlo Berti、Giorgio Catelani、Fabrizia Colonna、Alberto Marra
DOI:10.1016/s0040-4039(00)84515-3
日期:——
to five types of mono-, bis-, and tris(isopropylidene)acetals, among which the 3,4-0-iso-propylidene-6-0-(2-methoxyisopropyl) derivatives can be obtained in high yield and be useful intermediates for selective syntheses of 2-, 6-, and 2,6-0-substituted galactose derivatives.
Regioselective functionalization of monosaccharides is notoriously achieved using metal catalysis, lengthy protec-tion/deprotection-requiring synthetic strategies, various enzymes, or other methods that target cis-diols—all of which preclude their use with glucose derivatives. We report herein a new methodology using selected boronic acids as temporary protecting groups and describe its application
have studied the acyl migration in different monosaccharides using five different acylgroups by a combination of experimental, kinetic and theoretical tools. The results show that the anomeric configuration in the monosaccharide has a major influence on the migration rate, together with the relative configurations of the other hydroxylgroups and the nature of the migrating acylgroup. Full mechanistic