TEMPO/BAIB-mediated oxidation of 2,6- and 3,6-dihydroxy 1-thio glycopyranosides to the corresponding 1-thio uronic acid lactones is described. These locked 1-thio glycuronides can directly be used as donors in glycosidation reactions using the Ph(2)SO/Tf(2)O reagent system. Alternatively, selective opening of the lactone bridge liberates a hydroxyl function for ensuing glycosylations.
描述了由
化学和区域选择性的
TEMPO / BAIB介导的2,6-和3,6-二羟基1-
硫代糖
吡喃糖苷氧化为相应的1-
硫代糖醛酸内酯。使用Ph(2)SO / Tf(2)O试剂系统,可以将这些锁定的1-
硫代
乙二醛糖醛酸酯直接用作糖苷化反应中的供体。可替代地,内酯桥的选择性开放释放了用于随后糖基化的羟基功能。