N-結合型糖鎖の合成研究

抄録

Asparagine-linked oligosaccharides (N-glycans) have high diversity and are involved in a variety of important physiological events. To reveal the molecular basis of N-glycans functions, we synthesized N-glycans. We employed convergent synthetic route: two non-reducing end donors were connected to the reducing-end acceptor at the blanched mannose. Intermolecular hydrogen bonds involving acetamide were discovered to reduce the reactivity in glycosylations: the protection of NHAc as NAc₂ improved the reactivity. We also found that ether solvents enhanced the yields of key glycosylations between large fragments by stabilization of the oxocarbenium ion intermediate. To improve the α-selectivity of these glycosylations, we manipulated the remote participation because neighbouring group participation from 2 position of donor was not available.