Unified Approach to ent-Eudesmane-Type Terpenoid Synthesis: Total Synthesis of Sinupol and Eutyscoparin A

Abstract

ent-Eudesmane-type terpenoids constitute a large class of natural products derived from plants, animals, and bacteria. We describe a synthetic approach to two ent-eudesmane-type terpenoids, sinupol and eutyscoparin A, that relies on a key π-facial- and endo/exo-selective intramolecular Diels–Alder reaction to set the C-5–C-10 stereotriads. Further key transformations of trans-fused decalin include conversion to methyl ketone via a versatile thioester intermediate and appropriate functionalization toward target compounds.

Key words

ent-eudesmane - sinupol - eutyscoparin A - total synthesis - Diels–Alder reaction - protecting-group-free

• References

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