β-Carboline

Beta-carbolines are a chemical class of organic compounds derived from the core tryptamine structure, formed by ring closure between the indole and the ethylamine chain to give a tricyclic system. Members carry various substituents on the resulting ring system. The harmala alkaloids among them act as reversible inhibitors of monoamine oxidase A, a role central to the pharmacology of ayahuasca, where they allow orally ingested tryptamines to remain active. The tricyclic indole-fused ring closure is the defining feature of the class.