Practical Synthesis and Antifungal Investigation of Drimane Meroterpenoids Enabled by Nickel-Catalyzed Decarboxylative Coupling

Drimane meroterpenoids have drawn increasing attention in the discovery of novel pharmaceutical leads owing to their structural diversity and bioactivity variation, but further development is significantly impeded by the lack of an efficient modular route of preparation. A nickel-catalyzed decarboxylative cross-coupling paradigm has been established to expeditiously access a constellation of drimane meroterpenoids. The redox-active drimane precursor is a bench-stable coupling partner and is easily available from the inexpensive feedstock sclareol. This transformation features the tolerance of challenging functional groups (phenol, aldehyde, ester, etc.) and mild conditions with a low-cost nickel catalytic system. The synthetic utility is further highlighted by the direct scalable synthesis of challenging drimane meroterpenoids as diversifiable advanced intermediates for late-stage functionalizations. This method facilitated antifungal investigations and culminated in the discovery of compounds C8 and C3 as new antifungal leads against Rhizoctonia solani, with EC50 values of 4.9 and 7.2 μM, respectively.