Key Laboratory of Drug-Targeting and Drug Delivery Systems of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drugs and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, P. R. China.
Chem Asian J. 2019 Feb 1;14(3):454-461. doi: 10.1002/asia.201801779. Epub 2019 Jan 9.
A convenient and divergent approach was developed to prepare diverse bacterial 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) oligosaccharides containing a Kdo-α-(2→4)-Kdo fragment. The orthogonal protected α-(2→4) linked Kdo-Kdo disaccharide 3, serving as a common precursor, was divergently transformed into the corresponding 8-, 8'-, and 4'-hydroxy disaccharides 5, 7, and 14, respectively. Then, these alcohols were glycosylated, respectively, with the 5,7-O-di-tert-butylsilylene (DTBS) protected Kdo thioglycoside donors 1 or 2 in an α-stereoselective and high-yielding manner to afford a range of Kdo oligosaccharides. Finally, removal of all protecting groups of the newly formed glycosides resulted in the desired free Kdo oligomer.
开发了一种方便且多样化的方法来制备含有 Kdo-α-(2→4)-Kdo 片段的各种细菌 3-脱氧-D-甘露-辛-2-烯酸（Kdo）寡糖。正交保护的α-(2→4)连接的 Kdo-Kdo 二糖 3 作为共同前体，分别转化为相应的 8-、8'-和 4'-羟基二糖 5、7 和 14。然后，这些醇分别与 5,7-O-二叔丁基甲硅烷基（DTBS）保护的 Kdo 硫代糖苷供体 1 或 2 在α-立体选择性和高产率条件下进行糖苷化，得到一系列 Kdo 寡糖。最后，新形成的糖苷的所有保护基团的去除得到所需的游离 Kdo 低聚物。
