Terpenoids Derived from Linalyl Oxide, Part 4. The oxidation of davanone. Isolation and synthesis of the davana ethers, sesquiterpenes ofArtemisia Pallens

The photosensitized oxygenation of the β,γ-unsaturated ketonic sesquiterpene, davanone, is described. Treatment of davanone epoxide with an acid ion exchange resin yields a stereoisomeric mixture of the davana ethers, sesquiterpenoids containing two reduced furan rings.