Transannular <i>O</i>‑Heterocyclization: A Useful Tool for the Total Synthesis of Murisolin and 16,19-<i>cis</i>-Murisolin

Transannular <i>O</i>-heterocyclization is applied as a key step in a total synthesis. This highly stereoselective and metal-free transformation introduces four stereocenters in one step. It was chosen to be the pivotal step in the synthesis of Murisolin and 16,19-<i>cis</i>-Murisolin, two annonaceous acetogenins. The efficiency of this synthesis is further illustrated by a stereodivergent late-stage separation of both synthetic routes.