α,β-Unsaturated Diazoketones as Platforms in the Asymmetric Synthesis of Hydroxylated Alkaloids. Total Synthesis of 1-Deoxy-8,8a-diepicastanospermine and 1,6-Dideoxyepicastanospermine and Formal Synthesis of Pumiliotoxin 251D
作者:Barbara Bernardim、Vagner D. Pinho、Antonio C. B. Burtoloso
DOI:10.1021/jo301967w
日期:2012.11.2
A versatile and concise approach for the stereoselective synthesis of mono-, di-, and trihydroxylated indolizidines is presented in four to six steps from Cbz-prolinal and a diazophosphonate. The key steps involved a Wolff rearrangement, followed by a stereoselective dihydroxylation/epoxidation reaction, from an α,β-unsaturated diazoketone. The strategy also permits extension to the synthesis of many
从Cbz-脯氨酸和重氮膦酸酯的四至六个步骤中提出了一种立体选择性合成单羟基,二羟基和三羟基吲哚并吡啶的通用且简洁的方法。关键步骤涉及沃尔夫夫重排,然后是来自α,β-不饱和重氮酮的立体选择性二羟基化/环氧化反应。该策略还允许扩展到许多天然羟基化的吲哚并立定生物碱的合成,如pumiliotoxin 251D的正式合成所证明的。