Total Synthesis of Lucidumone: Attempted Shortcuts, Dead Ends and Lessons Learnt

Abstract

Lucidumone is a meroterpenoid isolated from the mushroom Ganoderma lucidum, displaying selective COX-2 inhibitory activity. In this work, we detail our synthetic efforts which led to the first enantioselective synthesis of lucidumone in 13 steps (longest linear sequence). Beyond the key retro-[4+2]/intramolecular Diels–Alder cascade, we discuss the difficulties regarding fragment assembly, introduction of the methyl ketone moiety and choice of adequate protecting group.

Key words

total synthesis - natural products - cycloaddition - pyrones - enantioselectivity

• References

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