Total Synthesis of (-)-Nodulisporic Acids D, C, and B: Evolution of a Unified Synthetic Strategy.

A unified synthetic strategy leading to the total synthesis of (-)-nodulisporic acids D, C, and B is described. Key synthetic transformations include a nickel-chromium-mediated cyclization, an aromatic ring functionalization employing a novel copper-promoted alkylation, a palladium-catalyzed cross-coupling cascade/indole ring construction, and a palladium-mediated regio- and diastereoselective allylic substitution/cyclization reaction, the latter to construct ring D.

Total Synthesis of (-)-Nodulisporic Acid D.

A convergent total synthesis of the architecturally complex indole diterpenoid (-)-nodulisporic acid D has been achieved. Key synthetic transformations include vicinal difunctionalization of an advanced α,ß-unsaturated aldehyde to form the E,F-trans-fused 5,6-ring system of the eastern hemisphere and a cascade cross-coupling/indolization protocol leading to the CDE multisubstituted indole core.