Photochemical Synthesis of Nepetanudone

Nepetanudone and nepetaparnone have been suspected of being the products of a photochemical dimerization of nepetapyrone. Both are natural products found in a variety of <i>Nepeta</i> species. The synthesis of (±)-nepetapyrone and subsequent photochemical experiments are described. (±)-Nepetanudone was produced upon irradiation of (±)-nepetapyrone, while (±)-nepetaparnone, a diastereomer of nepetanudone, was not observed