1-Methyl 1′-cyclopropylmethyl: an acid labile O-protecting group for polymer-supported oligosaccharide synthesis
作者:Eva Eichler、Fengyang Yan、Jennifer Sealy、Dennis M Whitfield
DOI:10.1016/s0040-4020(01)00582-8
日期:2001.7
6-tri-O-benzoyl-3-O-(R,S-1-methyl 1′-cyclopropylmethyl)-1-thio-β-d-galactopyranoside. Through a similar sequence of glycosylation of (MPEG)(DOX)OH, MCPM deprotection, glycosylation, functional group manipulation and cleavage the peracylated disaccharide GlcNAc(β1→3)Gal(β1→)DOXOAc was prepared. Finally, the donor 2,6-di-O-benzoyl-4-O-levulinoyl-3-O-(R,S-1-methyl 1′-cyclopropylmethyl)-1-thio-β-d-galactopyranoside
R,S -1-甲基1'-环丙基甲醇可被转化为其三氯乙酰亚胺酸酯衍生物。然后可将路易斯酸催化的醚化反应用于制备甲基环丙基甲基(MCPM)醚。因此,制备了乙基2,3,4-三-O-苄基-6- O-(R,S -1-甲基1'-环丙基甲基)-1-硫代-α/β-d-吡喃葡萄糖苷,并形成了连接基聚合物组合(MPEG)(DOX)OH糖基化。将MCPM基团用CH 2 Cl 2中的10%三氟乙酸裂解,并将得到的醇糖基化。在保护基团操纵并裂解后,分离出过乙酰化的二糖GlcNAc(β1→6)GlcOAc。同样是4,6- O将乙基1-硫代-β-d-吡喃半乳糖苷的-苯基硼酸酯二酯在O-3区域选择性醚化,并在硼酸酯裂解后将糖苯甲酰化,得到2,4,6-三-O-苯甲酰基-3 - O-(R,S -1-甲基1'-环丙基甲基)-1-硫代-β-d-吡喃半乳糖苷。通过相似的(MPEG)(DOX)OH糖基化序列,制备了MCPM脱保护,糖