Synthesis of the Lewis b hexasaccharide and squarate acid–HSA conjugates thereof with various saccharide loadings
作者:Anatoly Chernyak、Stefan Oscarson、Dominika Turek
DOI:10.1016/s0008-6215(00)00189-0
日期:2000.11
alpha-L-Fucp-(1 --> 2)-beta-D-Galp-(1 --> 3)-[alpha-L-Fucp-(1 --> 4)]-beta-D-GlcpNAc-(1 --> 3)-beta-D-Galp-(l --> 4)-beta-D-Glcp, has been synthesised using a convergent synthesis. Starting from ethyl 4,6-O-benzylidene-2-deoxy-2-phthalimido-1-thio-beta-D-glucopyranoside, a thioglycoside tetrasaccharide donor block, was constructed through two orthogonal glycosylations with glycosyl bromide donors. First,
Lewis b六糖,α-L-Fucp-(1-> 2)-β-D-Galp-(1-> 3)-[α-L-Fucp-(1-> 4)]-β -D-GlcpNAc-(1→3)-β-D-Galp-(1→4)-β-D-Glcp已经使用收敛合成法合成。从乙基4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚胺-1-硫代-β-D-吡喃葡萄糖苷开始,通过与糖基溴化物供体的两次正交糖基化,构建了硫代糖苷四糖供体嵌段。首先,使用三氟甲磺酸银作为促进剂引入半乳糖部分,然后在卤化物辅助条件下引入两个岩藻糖残基。最后,将该四糖以DMTST促进的偶联方式连接到带有间隔基的3I,4I-二醇乳糖受体上,以在脱保护后得到带有2-氨基乙基间隔基的衍生物Lewis b六糖。这与人类血清白蛋白(HSA)偶联,