Biomimetic Synthesis of Nor-Cedrene and Nor-Isozizaene Sesquiterpenoids and Exploration of Their Olfactive Properties.

We report the preparation of nor-bisabolyl epoxide 13 and its use as a common biomimetic intermediate for the synthesis of nor-sesquiterpenoids. Through a cationic cyclization cascade pathway, we prepared nor-isozizaenol 25, ultimately constituting an eight-step access to this complex sesquiterpenoid from inexpensive and abundant starting materials. Using a radical cyclization cascade pathway, we prepared nor-cedryl alcohol 26 from the same intermediate. Derivatization of these two products led to the discovery of two potent woody odorants of interest in perfumery.