Enantioselective [4 + 2] Cycloaddition/Cyclization Cascade Reaction and Total Synthesis of cis-Bis(cyclotryptamine) Alkaloids

Org Lett. 2021 Mar 5;23(5):1856-1861. doi: 10.1021/acs.orglett.1c00260. Epub 2021 Feb 23.

Abstract

The asymmetric catalytic synthesis of 3-cyclotryptamine substituted oxindoles through formal [4 + 2] cycloaddition/cyclization cascade is described. A wide range of cyclotryptamine derivatives were obtained in enantioenriched form under mild reaction conditions and were found to have potential anticancer activity. The strategy enables ready assembly of cyclotryptamine subunits at the C3a-C3a' positions with two quaternary stereogenic centers in cis-selectivity, leading to the concise synthesis of optically active cis-bis(hexahydropyrroloindole) and others of the cyclotryptamine alkaloid family.

Publication types

  • Research Support, Non-U.S. Gov't