The levorotatory diol 7 has been sequentially monosilylated, dehydrated, and oxidized at the allylic methylene group to provide (+)-12. The enantiomeric dextrorotatory diol 7 has been directed down a different sequence of steps involving monosilylation, dehydration, hydroboration, Swern oxidation, and regioselective introduction of a conjugated double bond to generate (−)-33. The novel feature of these
左旋二醇7已经在烯丙基亚甲基上顺序地被甲
硅烷基化,脱
水和氧化,以提供(+)- 12。对映体右旋二醇7的制备步骤不同,包括单
硅烷化,脱
水,
硼氢化,Swern氧化和共轭双键的区域选择性引入,以生成(-)- 33。这些转化的新颖特征是,已从对映体相关的前体中获得了两个具有正确绝对构型的关键脱氧碳螺螺核苷酸中间体。还报道了由这些螺环式
环戊烯酮形成新颖结构类型的新颖2'-脱氧
核糖核苷的高度实用且可靠的方法。