as a glycosyl acceptor for further elongation. The preparation of biologically important linear and branched oligomannoses incorporated into HIV gp120 demonstrates that iteration of this one-pot sequence leads to very straightforward oligosaccharide assembly. As an additional result, a rapid approach has been disclosed for accessing a 3,6-OH mannose building-block to be incorporated in branched structures
装备有2-O-Fmoc基团的
甘露糖基三卤代乙酰
氨基
乙酸供体可通过糖基化反应中的催化Bi(OTf)(3)有效激活。尽管Fmoc基团有预期的参与作用,但发现反应溶剂对于获得高度选择性的α-
甘露糖基化起决定性作用。然后可以在进行糖苷化的同一容器中,简单地从获得的二
寡糖中除去Fmoc 2-O-保护基。所得的
寡糖因此可以直接用作糖基受体以进一步延长。整合入HIV gp120的具有
生物学重要性的线性和支链低聚
甘露糖的制备表明,这一一锅法序列的迭代可导致非常简单的
寡糖组装。另外的结果是,公开了一种访问3的快速方法,6-OH
甘露糖构建基要结合到支链结构中。这依赖于二-O-亚苄基
甘露糖中间体的双重还原开口,其区域选择性似乎与五元亚苄基的构型无关。