A short efficient enantioselectivesynthesis leading directly to (+)-(S)-kurasoin B has been achieved in 5 steps and 25% overall yield from (2E)-ethyl-4-phenylbut-2-enoate using Sharpless asymmetricdihydroxylation and CH3NO2-assisted, or Yb(OTf)3-catalyzed, regioselective C-3 coupling of indole as the key steps.
使用Sharpless不对称二羟基化反应和CH,仅需5个步骤即可完成短时有效的对映选择性合成,可直接导致(+)-(S)-苦瓜素B,并且从(2 E)-4-苯基丁-2-烯酸乙酯的总收率达到25%3 NO 2辅助或Yb(OTf)3催化的吲哚的区域选择性C-3偶联是关键步骤。