Divergent total synthesis of 1,6,8a-tri-epi-castanospermine and 1-deoxy-6,8a-di-epi-castanospermine from substituted azetidin-2-one (β-lactam), involving a cascade sequence of reactions as a key step
作者:Dipak Kumar Tiwari、Kishor Chandra Bharadwaj、Vedavati G. Puranik、Dharmendra Kumar Tiwari
DOI:10.1039/c4ob00948g
日期:——
divergent, short, and novel total synthesis of 1,6,8a-tri-epi-castanospermine (7) and 1-deoxy-6,8a-di-epi-castanospermine (8) has been developed via a common precursor, 15, obtained from D-mannitol derived β-lactam. The key step involves a one pot cascade sequence of trimethyl sulfoxonium ylide based cyclization of epoxy sulfonamide 14via epoxide ring opening, one carbon homologation followed by intramolecular
的发散,的1,6,8a三-短,和新颖的全合成外延-castanospermine(7)和1-脱氧6,8a二-外延-castanospermine(8)已开发通过一个共同的前体,15由D-甘露醇衍生的β-内酰胺获得。的关键的步骤涉及三甲基氧化锍叶立德环氧基磺酰胺环化的一锅级联序列14经由环氧化物开环,一个碳同系化,随后进行分子内环化。