A novel approach to the total synthesis of naturally occurring furanoflavones and furanochalcones is described. Angular and linear furanoflavones and furanochalcones have been prepared in just four steps, using economical reagents and simple reaction conditions. The key step of our approach is the formation of crucial precursors, 5-acetyl-4-hydroxy-coumarone and 5-acetyl-6-hydroxy-coumarone by Amberlyst 15-catalyzed cyclization of phenoxyacetal.
本文描述了一种合成天然存在的
呋喃黄酮和
呋喃黄酮醌的新方法。角型和线型
呋喃黄酮及
呋喃黄酮醌仅需四个步骤即可合成,采用经济的试剂和简单的反应条件。我们方法的关键步骤是通过Amberlyst 15催化的苯氧基
甲醛环化反应形成重要前体5-乙酰基-
4-羟基
香豆素和5-乙酰基-6-羟基
香豆素。