Gigantine
Gigantine is a tetrahydroisoquinoline alkaloid found in Carnegiea gigantea and other related cactus species. It was first discovered along with macromerine in 1967. Gigantine is found in significant quantities in many mescaline-containing cactus species, but it is unclear whether it contributes to their psychoactive effects. The compound has been suspected to be hallucinogenic based on animal studies in cats and monkeys, but has not been evaluated in humans.