Total Synthesis of Seven Indole Alkaloids
Unified Total Synthesis of Pyrroloazocine Indole Alkaloids Sheds Light on Their Biosynthetic Relationship.
J. Am. Chem. Soc. 2018;
17. April 2018 (online)
Key wordsPasserini reaction - photoredox catalysis - gold catalysis - indole alkaloids - pyrroloazocine motif
A set of seven indole alkaloids were synthesized by the Echavarren group through common precursor I. The alkaloids all contain a pyrroloazocine core and were shown to reverse multidrug resistance in cancer cells. Further experiments provided insights into a biosynthetic mechanism.
The use of an imine formation–lactamization–rearrangement cascade provides rapid access to C. A set of homologations and gold cyclizations led to the desired carbon framework in I. Functional group manipulations then led to a collection of related natural products.