Lewis Acid Catalyzed Ring-Opening Reactions of Sugar-Derived Semicyclic N,O-Acetals
作者:Masaharu Sugiura、Hiroyuki Hagio、Shu Kobayashi
DOI:10.1002/1522-2675(200211)85:11<3678::aid-hlca3678>3.0.co;2-0
日期:2002.11
efficiently synthesized from regular acetyl or methyl glycosides (glucopyranoside, ribofuranoside, arabinofuranoside, and 2-deoxyribofuranoside) and a carbamate by treatment of trimethylsilyl trifluoromethanesulfonate and 4 A molecular sieves. It was found that these N-glycosides underwent Lewis acid catalyzed ring-opening reactions with silylated nucleophiles to give ring-opened amino alcohols with good-to-high
N-(烷氧基羰基)-N-糖苷(聚氧半环N,O-缩醛) 由常规乙酰基或甲基糖苷(吡喃葡萄糖苷、呋喃核糖苷、阿拉伯呋喃糖苷和2-脱氧呋喃核糖苷) 和氨基甲酸酯通过三甲基甲硅烷基三氟甲磺酸酯和4 A 处理有效合成分子筛。发现这些N-糖苷与硅烷化亲核试剂发生路易斯酸催化的开环反应,得到具有良好至高非对映选择性的开环氨基醇。揭示了反应性顺序,2-脱氧呋喃糖苷 > 阿拉伯呋喃糖苷 > 呋喃糖苷 > 吡喃葡萄糖苷。还用硅烷或氢化二异丁基铝研究了开环还原。发现合适的还原剂取决于所使用的 N-糖苷。糖苷酶抑制剂,(2S,3R,