School of Physical Science and Technology, ShanghaiTech University , 100 Haike Road, Shanghai 201210, China.
State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China.
J Org Chem. 2017 Mar 17;82(6):3062-3071. doi: 10.1021/acs.joc.7b00057. Epub 2017 Mar 2.
The β-(1→2)-linked 6-deoxy-l-altropyranose di- to pentasaccharides 2-5, relevant to the O-antigen of the infectious Yersinia enterocolitica O:3, were synthesized for the first time. The challenging 1,2-cis-altropyranosyl linkage was assembled effectively via glycosylation with 2-O-benzyl-3,4-di-O-benzoyl-6-deoxy-l-altropyranosyl ortho-hexynylbenzoate (7) under the catalysis of PPhAuNTf. NMR and molecular modeling studies showed that the pentasaccharide (5) adopted a left-handed helical conformation.
β-(1→2)-连接的 6-去氧-l-阿洛吡喃糖二至五聚糖 2-5，与传染性肠炎耶尔森氏菌 O:3 的 O-抗原有关，首次被合成。具有挑战性的 1,2-顺式阿洛吡喃糖苷键通过用 2-O-苄基-3,4-二-O-苯甲酰基-6-去氧-l-阿洛吡喃糖基正己炔基苯甲酸酯（7）在 PPhAuNTf 的催化下进行糖苷化有效地组装。NMR 和分子建模研究表明，五聚糖（5）采用左手螺旋构象。
