The above discouraging results prompted us to revise our synthetic plan. We envisioned that combining in one step functionalization of the specific position (pendent methyl group) and retro-cycloisomerization event may serve as a solution to our problem. The new concept is briefly described on Scheme 3. We thought that activation of the exocyclic double bond on (-)caryophyllene oxide (11) with a suitable reagent could trigger a concomitant cationic (or radical) mediated retro-cycloisomerization and functionalization of C-14 (intermediate II). Subsequent functional group transformation would provide the desired monocyclic precursor ent-4. Scheme 3. Revised retrosynthetic analysis combining retrocycloisomerization and functionalization of C-14.