Synthesis of the Tetracyclic Core of the Daphlongeranines

Org Lett. 2025 Oct 17;27(41):11485-11490. doi: 10.1021/acs.orglett.5c03362. Epub 2025 Oct 7.

Abstract

The first synthesis of the tetracyclic core of the daphlongeranine natural product family is reported. Containing a tricyclic core unique to this subfamily of the Daphniphyllum alkaloids and featuring two quaternary carbons, this 11-step synthetic route featured the application of a three-step spirocyclization strategy and development of a new intramolecular Pd-catalyzed cyclization reaction. Additionally, the route included the application of an XAT-initiated Giese addition and demonstration of an enantioselective synthesis of the bicyclic core.