High 1,3-<i>trans</i> Stereoselectivity in Nucleophilic Substitution at the Anomeric Position and β-Fragmentation of the Primary Alkoxyl Radical in 3-Amino-3-deoxy-ribofuranose Derivatives: Application to the Synthesis of 2-<i>epi</i>-(−)-Jaspine B
作者:Alma Sánchez-Eleuterio、Leticia Quintero、Fernando Sartillo-Piscil
DOI:10.1021/jo200639t
日期:2011.7.1
that orients pseudoequatorially to the benzylamine group placed at the C-3 position. In addition, an unusual β-fragmentation of a primary alkoxyl radical generated from its corresponding N-phthalimide derivative was achieved, and thus taking advantages of both reactions, the total synthesis of 2-epi-(−)-jaspine B was completed.
据报道,在3-氨基-3-脱氧核糖呋喃糖衍生物的异头位置的亲核取代中具有高的逆立体选择性。这种空前的立体选择性是根据对五元环氧碳鎓离子的“内侧面”的优先亲核攻击来解释的,该五元环氧碳鎓离子伪伪地与位于C-3位置的苄胺基团取向。另外,获得了由其相应的N-邻苯二甲酰亚胺衍生物产生的伯烷氧基的不寻常的β-片段化,因此利用这两个反应的优势,完成了2- epi -(-)-jaspine B的全合成。