A Flexible Enantioselective Total Synthesis of Diospongins A and B and Their Enantiomers Using Catalytic Hetero-Diels−Alder/Rh-Catalyzed 1,4-Addition and Asymmetric Transfer Hydrogenation Reactions as Key Steps
A unified enantioselective route to totalsynthesis of diospongins A and B and their enantiomers has been developed employing achiral starting materials. All three stereocenters were introduced by means of catalytic reactions.