Synthesis of the Core Ring System of the Yuzurimine-Type <i>Daphniphyllum</i> Alkaloids by Cascade Condensation, Cyclization, Cycloaddition Chemistry
作者:Iain Coldham、Luke Watson、Harry Adams、Nathaniel G. Martin
DOI:10.1021/jo2000868
日期:2011.4.1
Addition of hydroxylamine to substituted 4-chlorobutanals gives intermediate nitrones that undergo tandem cyclization and then intramolecular dipolar cycloaddition to give the core ring system of the yuzurimine-type natural products. Ring-opening of the isoxazolidines gives amino alcohols that can be converted to 1,3-oxazines, representing the tetracyclic core of alkaloids such as daphcalycic acid
将羟胺加至取代的4-氯丁醛中得到中间体硝酮,其进行串联环化,然后进行分子内偶极环加成,从而得到yuzurimine-型天然产物的核心环系统。异恶唑烷的开环得到氨基醇,该氨基醇可以转化为1,3-恶嗪,代表生物碱的四环核心,如萘乙酸和萘乙酸。