total synthesis of the polycyclic polyprenylated acylphloroglucinol (PPAP) natural product hyperforin from 2-methylcyclopent-2-en-1-one is reported. This route was enabled by a diketene annulation reaction and an oxidative ring expansion strategy designed to complement the presumed biosynthesis of this complex meroterpene. The described work enables the preparation of a highly substituted bicyclo[3.3
Stereoselective total synthesis of (±)-hyperforin via intramolecular cyclopropanation
作者:Masahiro Uwamori、Masahisa Nakada
DOI:10.1016/j.tetlet.2013.02.021
日期:2013.4
by a three-step sequence: intramolecular cyclopropanation, construction of the C8 all-carbonquaternarystereogeniccenter, and subsequent regioselective ringopening of cyclopropane. Further steps to obtain (±)-hyperforin include chemo- and stereoselective hydrogenation to generate the C7 stereogeniccenter, formation of the C9 isopropyl ketone using an organocerium reagent, and cross-metathesis at
ent-hyperforin was described here in detail. Keys to the success were a catalytic asymmetric Diels–Alder reaction, a stereoselective Clasien rearrangement, an intramolecular aldol cyclization, and a vinylogous Pummerer rearrangement. Along with the successful synthetic route, several attempted approaches toward the construction of bicyclo[3.3.1] core and the C2 oxidation were discussed.
Modular Total Syntheses of Hyperforin, Papuaforins A, B, and C via Gold(I)-Catalyzed Carbocyclization
作者:Gabriel Bellavance、Louis Barriault
DOI:10.1021/acs.joc.8b00426
日期:2018.7.6
the past decade. Herein, we report the concise total syntheses of four naturalproducts PPAPs, of which some have antibacterial properties, notably hyperforin and papuaforin A. The salient features of this strategy are the short and gram-scalable synthesis of densely substituted PPAPs scaffolds via a Au(I)-catalyzed carbocyclization and the late-stage functionalization for a unified access to a wide variety