Enantioselective Total Synthesis of (-)-Alstoscholarisine A

J Am Chem Soc. 2016 Mar 2;138(8):2560-2. doi: 10.1021/jacs.6b00625. Epub 2016 Feb 18.

Abstract

We report a concise and highly enantioselective total synthesis of (-)-alstoscholarisine A (1), a recently isolated monoterpenoid indole alkaloid that has significant bioactivity in promoting adult neuronal stem cells proliferation. A highly enantioselective (99% ee), intramolecular Ir-catalyzed Friedel-Crafts alkylation of indole 9 with a secondary allylic alcohol was utilized to establish the first stereogenic center upon which the other three contiguous chiral centers were readily set by a highly stereoselective tandem 1,4-addition and aldol reaction. The key tetrahydropyran was constructed through a hemiacetal reduction, and the final aminal bridge was forged by a one-pot reductive amination/cyclization. The conciseness of this approach was highlighted by building core bonds in each step with a minimalist protecting group strategy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Secologanin Tryptamine Alkaloids / chemical synthesis*
  • Stereoisomerism

Substances

  • Secologanin Tryptamine Alkaloids
  • alstoscholarisine H