strategy of intramolecular reductive coupling to construct the cyclopenta[b]benzofuran skeleton, the shortest and most efficient synthetic method hitherto was now established to rocaglamide 1 and its 2,3-di-epi analogue 3 in racemic form by Michael addition, SmI2-promoted intramolecular keto–ester coupling, amination of the ester intermediate, and reduction of carbonyl with Me4NBH(OAc)3. Several steps were
通过引入分子内还原偶联的策略来构建
环戊二烯[b]
苯并呋喃骨架,现在通过迈克尔加成建立了迄今为止最短、最有效的罗卡格酰胺1及其外消旋形式的2,3-二表类似物3的合成方法,
SmI2 促进分子内酮-酯偶联、酯中间体的胺化以及用 Me4NBH(OAc)3 还原羰基。几个步骤具有高度立体选择性甚至立体特异性。
生物测定结果表明,与
印楝素相比,1和3对小菜蛾的驱避效果要好得多;1 的杀虫活性高于
印楝素对菜青虫、小菜蛾、甜菜夜蛾和棉铃虫的杀虫活性,但 3 的杀虫活性较低。 (© Wiley-
VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)