Multigram-scale synthesis of an orthogonally protected 2-acetamido-4-amino-2,4,6-trideoxy-d-galactose (AAT) building block
作者:A.E. Christina、V.M. Blas Ferrando、F. de Bordes、W.A. Spruit、H.S. Overkleeft、J.D.C. Codée、G.A. van der Marel
DOI:10.1016/j.carres.2012.02.015
日期:2012.7
Reported is the gram-scale synthesis of tert-butyldiphenylsilyl 4-(N-benzyloxycarbonyl)-amino-2-azido-2,4,6-trideoxy-beta-D-galactopyranoside, which represents an orthogonally protected 2,4-diamino-D-fucose building block, a common constituent of various zwitterionic polysaccharides. The building block has been synthesized from D-glucosamine in 19% overall yield over 14 steps, requiring 5 chromatographic
报告的是叔丁基二苯基甲硅烷基4-(N-苄氧基羰基)-氨基-2-叠氮基2,4,6-三苯氧基-β-D-吡喃半乳糖苷的克级合成,其代表正交保护的2,4-二氨基- D-岩藻糖结构单元,是各种两性离子多糖的常见成分。该结构单元是由D-氨基葡萄糖合成的,在14个步骤中的总产率为19%,需要进行5次色谱纯化。合成中的关键步骤是引入C-4氨基取代基,该步骤已通过一锅三步程序完成,涉及区域选择性C-3-O-三氯乙酰胺酸酯的形成,C-4-O-三氟甲磺酸和分子内取代。该结构单元可用作受体,并易于转化为供体糖苷。