both cases, the readily crystallized diacetonides have a 2,3-cis-diol relationship in the product lactone. An efficient double inversion of the configuration at C-4 and C-5 of the product from d-fructose gives access to the formal Kiliani product from l-psicose. Branched carbohydrate lactones are likely to be of significant value as chirons for homochiral targets with functionalized quaternary centres
经保护的支链糖内酯可通过Kiliani-
丙酮化序列在容易获得的酮糖如d-
果糖和l-
山梨糖上获得。在两种情况下,容易结晶的二
丙酮化物在产物内酯中具有2,3-顺
-二醇关系。来自d-
果糖的产物在C-4和C-5处的构型的有效两次转化使得能够获得来自l--糖的形式Kiliani产物。支链
碳水化合物内酯作为具有功能化四元中心的同手性目标的卡隆,可能具有重要的价值。