The Indole reference article from the English Wikipedia on 24-Apr-2004
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Indole

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An indole is an organic molecular structure, consisting of the bicyclic of benzene and a pyrrole. Indoles are found in many organisms, and many indoles are biologically active.

Indole
Indole

Indole is a precursor of the widely-occuring amino acid tryptophan. Some alkaloids are indoles, including the hallucinogenic tryptamines psilocybin, mescaline, and LSD. The structure is also found in many naturally-occuring human neurotransmitters, such as serotonin.

An indole could be described as the union of a 6-membered benzene ring with a five-membered pyrrole ring. The pyrrole has one nitrogen atom present.

The name indole is derived from indigo, a blue pigment obtained from some plant species. The indigo molecule comprises two indole units joined together.