Chemical synthesis of a synthetically useful L-galactosaminuronic acid building block  

作　　者：QIN Chun-Jun HOU Hong-Li DING Mei-Ru QI Yi-Kuan TIAN Guang-Zong ZOU Xiao-Peng FU Jun-Jie HU Jing YIN Jian 

机构地区：[1]Key Laboratory of Carbohydrate Chemistry and Biotechnology,Ministry of Education,School of Biotechnology,Jiangnan University,Wuxi 214122,China [2]Wuxi School of Medicine,Jiangnan University,Wuxi 214122,China

出　　处：《Chinese Journal of Natural Medicines》2022年第5期387-392,共6页中国天然药物（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.22077052,21877052,21907039);the China Postdoctoral Science Foundation(2020M681487);the National Key R&D Program of China(2020YFA0908304);the Natural Science Foundation of Jiangsu Province(BK20180030,BK20190575);the National First-class Discipline Program of Light Industry Technology and Engineering(LITE2018-14);the 111 Project(111-2-06);the Open Project of Key Laboratory of Carbohydrate Chemistry and Biotechnology(Jiangnan University),Ministry of Education(KLCCB-KF202005);the Natural Science Foundation of Xuzhou(KC19154).

摘　　要：Most bacterial cell surface glycans are structurally unique, and have been considered as ideal target molecules for the developments of detection and diagnosis techniques, as well as vaccines. Chemical synthesis has been a promising approach to prepare well-defined oligosaccharides, facilitating the structure-activity relationship exploration and biomedical applications of bacterial glycans. L-Galactosaminuronic acid is a rare sugar that has been only found in cell surface glycans of gram-negative bacteria. Here, an orthogonally protected L-galactosaminuronic acid building block was designed and chemically synthesized. A synthetic strategy based on glycal addition and TEMPO/BAIB-mediated C6 oxidation served well for the transformation of commercial L-galactose to the corresponding L-galactosaminuronic acid. Notably, the C6 oxidation of the allyl glycoside was more efficient than that of the selenoglycoside. In addition, a balance between the formation of allyl glycoside and the recovery of selenoglycoside was essential to improve efficiency of the NIS/TfOH-catalyzed allylation. This synthetically useful L-galactosaminuronic acid building block will provide a basis for the syntheses of complex bacterial glycans.

关 键 词：L-galactosaminuronic acid Chemical synthesis Orthogonal protection Glycal addition C6 oxidation 

分 类 号：R313[医药卫生—基础医学]