Collective Total Synthesis of Casbane Diterpenes: One Strategy, Multiple Targets.

ABSTRACT: Of the more than 100 casbane diterpenes known to date, only the eponymous parent hydrocarbon casbene itself has ever been targeted by chemical synthesis. Outlined herein is a conceptually new approach that brings not a single but a variety of casbane derivatives into reach, especially the more highly oxygenated and arguably more relevant members of this family. The key design elements are a catalyst-controlled intramolecular cyclopropanation with or without subsequent equilibration, chain extension of the resulting stereoisomeric cyclopropane building blocks by chemoselective hydroboration/cross-coupling, and the efficient closure of the strained macrobicyclic framework by ring-closing alkyne metathesis. A hydroxy-directed catalytic trans-hydrostannation allows for late-stage diversity. Th

SUBMITTER: Loffler LE 

PROVIDER: S-EPMC7986786 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature