Agoston Károly, Geyer Armin
Fakultät für Chemie und Pharmazie, Universität Regensburg, Germany.
Chemistry. 2005 Oct 21;11(21):6407-13. doi: 10.1002/chem.200500515.
Trifluoromethanesulfonic acid anhydride (triflic acid anhydride) transforms the bicyclic thiazolidinlactam 1 a into the crystalline elimination product 2, in which all four secondary hydroxyl groups of 1 a are differently functionalized. Compound 2 can then add nucleophiles with high chemo- and stereoselectivity. Altogether, the four secondary hydroxyl groups of D-glucuronic acid are selectively transformed without the need for any O-protecting groups. Minimizing the number of O-protecting groups is a prerequisite for the use of sugar scaffolds in molecular libraries. The hapalosin analogues 15, 16, 19, and 22 outline the strategy towards O-diversified glucose derivatives.
三氟甲磺酸酐（三氟磺酸酐）将双环噻唑烷内酰胺1a转化为结晶消除产物2，其中1a的所有四个仲羟基都被不同程度地官能化。然后化合物2可以以高化学和立体选择性添加亲核试剂。总之，D-葡萄糖醛酸的四个仲羟基被选择性地转化，无需任何O-保护基团。尽量减少O-保护基团的数量是在分子文库中使用糖支架的前提条件。哈帕洛辛类似物15、16、19和22概述了制备O-多样化葡萄糖衍生物的策略。
