Ambrein is a triterpene alcohol that is the chief constituent of ambergris, a secretion from the digestive system of the sperm whale, and has been suggested as the possible active component producing the supposed aphrodisiac effects of ambergris. Although ambrein itself is odorless, it serves as the biological precursor for a number of aromatic derivatives such as ambroxan and is thought to possess fixative properties for other oderants.