Synthesis of (−)-agathic acid and (−)-copalic acid from andrographolide via a regioselective Barton-McCombie reaction
作者:Zhengyuan Xin、Yunlong Lu、Xiaolan Xing、Jingjie Long、Jiabin Li、Xiaowen Xue
DOI:10.1016/j.tet.2015.12.022
日期:2016.1
The first synthesis of the ent-labdane diterpenoid (−)-agathic acid (1) with antibacterial activity is described. A chiral pool approach was employed with a linear sequence of 14 steps starting from readily available and inexpensive andrographolide. The regioselective deoxygenation in terms of Barton-McCombie free radical reaction completed a key step in the synthesis. (−)-Copalic acid (2), an analogue
描述了具有抗菌活性的对-拉丹二萜(-)-agathic酸(1)的首次合成。从容易获得且廉价的穿心莲内酯开始,采用具有14个步骤的线性序列的手性池方法。就Barton-McCombie自由基反应而言,区域选择性脱氧完成了合成中的关键步骤。(-)-椰油酸(2),(-)-agathic酸的类似物,已从关键中间体7分五步方便地合成。