Irone

Chemical structures of (-)-cis-γ-irone (top) and (-)-cis-α-irone

Irones are a group of methylionone odorants used in perfumery, derived from iris oil,^[1] e.g. orris root. The most commercially important of these are:

• (-)-cis-γ-irone, and
• (-)-cis-α-irone

Irones form through slow oxidation of triterpenoids in dried rhizomes of the iris species, Iris pallida. Irones typically have a sweet floral, iris, woody, ionone, odor.