A Siloxane-Bridged Glycosyl Donor Enables Highly Stereoselective β-Xylulofuranosylation
作者:Bo-Shun Huang、Todd L. Lowary
DOI:10.1021/acs.joc.0c01008
日期:2020.12.18
We report a siloxane-protected donor (7) for the highly stereoselective formation of β-(2,3-cis)-xylulofuranosyl bonds. Glycosylation reactions with 7 gave >80% yields, and only β-xylulofuranosides were isolated in all cases. The utility of 7 for the synthesis of complex glycans was shown by its successful application to the preparation of the repeating unit from the lipopolysaccharide O-antigen of
我们报告了硅氧烷保护的供体(7)的β-(2,3-顺式)-xylulofuranosyl键的高度立体选择性形成。7种糖基化反应的收率> 80%,在所有情况下仅分离出β-木氟呋喃糖苷。的效用7为复合聚糖的合成所示的成功应用从脂多糖O-抗原制备的重复单元的至小肠结肠炎耶尔森菌血清型○:5 / O:5,27。该结构是具有两个β-木酮呋喃糖残基的五糖。使用7,同时引入了具有出色的立体声控制功能。