The first syntheses of the enantiomers of naturally occurring
aquilanols
A and B, two unprecedented 7/10 bicyclic sesquiterpenoids, are presented.
Key features are a retro-cycloisomerization event on (−)-caryophyllene
oxide to formulate the 11-membered carbocycle and an intramolecular
epoxide opening to construct the bicyclic skeleton. The latter provides
evidence of the plausible biosynthesis of natural compounds, rendering
our syntheses biomimetic. Selective access to other medium-sized carbocyclic
oxygenated compounds was achieved, enhancing the structural diversity
of the final products.