The Aspidosperma alkaloids leuconoxine, melodinine E, and mersicarpine were synthesized. The approach features a key cascade radical reaction. A 1,5-hydrogen atom transfer is followed by spontaneous 5-exo-trig cyclization to construct the central indoline architecture. Late-stage differentiation of the radical cyclization product by chemoselective oxidation allows production of either the leuconoxine/melodinine E
合成了天冬子孢子碱的
生物碱亮
氨酸,
甜菜碱E和美卡西平。该方法具有关键的级联自由基反应。1,5-
氢原子转移后,自发地进行5-exo-trig环化,以构建中央二
氢吲哚结构。通过
化学选择性
氧化对自由基环化产物进行后期区分,可以产生亮
氨酸
氧代/ melodinine E或马西卡平结构。