A Formal Synthesis of (±)-Arborisidine

Org Lett. 2024 May 10;26(18):3801-3805. doi: 10.1021/acs.orglett.4c00928. Epub 2024 Apr 26.


Herein, we report a formal synthesis of (±)-arborisidine via the creation of Jiao's intermediate with the critical caged structure. Starting from tryptamine, a Pictet-Spengler cyclization forged the piperidine ring, a Pd-catalyzed indole allylation and ring-closing metathesis protocol afforded a bridged aza-bicyclo[3.3.1]nonane moiety, and an intramolecular N-alkylation closed the final pyrrolidine ring. This study provides a new approach to the unique caged framework of arborisidine and relevant alkaloids.