Asymmetric Allylboration and Ring Closing Alkene Metathesis: A Novel Strategy for the Synthesis of Glycosphingolipids
作者:Anthony G. M. Barrett、Jennifer C. Beall、D. Christopher Braddock、Kevin Flack、Vernon C. Gibson、Matthew M. Salter
DOI:10.1021/jo000690p
日期:2000.10.1
A novel strategy for the synthesis of D,L-glucosylceramide 1, a member of the glycosphingolipid class of natural products is described. Reagent-controlled asymmetric Brown allylboration gave excellent stereochemical control in the construction of adjacent stereocenters in the sphingoid base portion of the molecule. The trans-configured double bond was obtained as a single geometrical isomer by use
描述了一种合成D,L-葡萄糖基神经酰胺1(一种糖鞘脂类天然产物的成员)的新策略。试剂控制的不对称布朗烯丙基硼化在分子鞘氨醇碱基部分中相邻立体中心的构建中提供了出色的立体化学控制。通过使用Schrock卡宾[(CF3)2MeCO] 2Mo(= CHCMe2Ph)(= NC6H3-2,6-i-Pr2 ++ +)的硅链烯烃复分解法,将反式构型双键作为单个几何异构体获得原位PhLi诱导的中间体5,6-二氢-2H-1,2-奥沙西林开环,然后在DMSO中与TBAF进行原去甲硅烷基化。通过长链酰胺的形成和整体脱保护完成了合成。