Catalytic Enantioselective Total Synthesis of the Picrotoxane Alkaloids (−)-Dendrobine, (−)-Mubironine B, and (−)-Dendroxine

A concise enantioselective total synthesis of three sesquiterpenoid alkaloids-(-)-dendrobine, (-)-mubironine B, and (-)-dendroxine-is presented, which highlights the state-of-art catalytic methods, including enantioselective Diels-Alder cycloaddition, iron-catalyzed aerobic lactonization, copper-catalyzed cycloisomerization, and free-radical-initiated hydroazidation.