Lactucin
Lactucin is a bitter substance that forms a white crystalline solid and belongs to the group of sesquiterpene lactones. It is found in some varieties of lettuce and is an ingredient of lactucarium. It is also found in dandelion coffee. It has been shown to have analgesic and sedative properties, which are speculated to occur via modulation of the GABAA receptor, as well as antimalarial activity.