Dai Shuolu, Teng Minggang, Xu Erjuan, Xu Min, Luo Min, Chen Chen, Chai Huifang, Chi Yonggui Robin, Wu Jian, Lv Wen-Xin
State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guizhou University, Guiyang 550025, China.
School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore.
Org Lett. 2024 Dec 20;26(50):10910-10914. doi: 10.1021/acs.orglett.4c04074. Epub 2024 Dec 5.
In the chemical synthesis or modification of saccharides, regioselective protection of the many similar OH groups in saccharides is necessary but remains a major challenge. In particular, the regio- and stereoselective conversion of C(1,2)-OH has great synthetic potential in carbohydrate synthesis but has largely remained untapped. Here, an in situ proton-producing system mediated by boronic acid was found and employed for site-selective ketalization of various unprotected saccharides. This strategy is characterized by the controlled production of protons mediated by the dynamic, reversible covalent binding of boronic acid and saccharides. This method provides great convenience for the concise synthesis of complex saccharides, as illustrated by the streamlined degradation and reconstruction of disaccharides.
在糖类的化学合成或修饰中，对糖类中许多相似的羟基进行区域选择性保护是必要的，但仍然是一个重大挑战。特别是，C(1,2)-OH的区域和立体选择性转化在碳水化合物合成中具有巨大的合成潜力，但在很大程度上尚未得到开发。在此，发现了一种由硼酸介导的原位产质子体系，并将其用于各种未保护糖类的位点选择性缩酮化反应。该策略的特点是通过硼酸与糖类的动态、可逆共价结合来控制质子的产生。这种方法为复杂糖类的简洁合成提供了极大的便利，二糖的简化降解和重建就说明了这一点。
