Indoles are a class of heterocyclic aromatic organic compounds with a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring. They are naturally occurring in many plants and animals and have significant biochemical roles, including being precursors to several amino acids like tryptophan. Indoles are also important in the synthesis of pharmaceuticals, agricultural chemicals, and dyes.
