Short, Divergent, and Enantioselective Total Synthesis of Bioactive <i>ent</i>-Pimaranes.

We present the first total synthesis of eight <i>ent</i>-pimaranes via a short and enantioselective route (11-16 steps). Key features of the divergent synthesis are a Sharpless asymmetric dihydroxylation, a Brønsted acid catalyzed cationic bicyclization, and a mild Rh-catalyzed arene hydrogenation for rapid access to a late synthetic branching point. From there on, selective functional group manipulations enable the synthesis of <i>ent</i>-pimaranes bearing different modifications in the A- and C-rings.