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4-HO-MPMI

Chemical compound

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated September 7, 2026
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4-HO-MPMI, also known as 4-hydroxy-N-methyl-(α,N-trimethylene)tryptamine or as lucigenol, is a psychedelic drug of the pyrrolidinylmethylindole and cyclized tryptamine families.

01Pharmacology

Pharmacodynamics

The affinity (Ki) of 4-HO-MPMI for the serotonin 5-HT2A receptor has been found to be 13 nM. It produces psychedelic-appropriate responding in animal tests with similar potency as DOI. The drug has two enantiomers, with only the (R)-enantiomer being active.

02Chemistry

Analogues

Analogues of 4-HO-MPMI include MPMI, 5-MeO-MPMI, 5F-MPMI, CP-135,807, 4-HO-McPeT, 4-HO-pyr-T, and SN-22, among others.

03History

4-HO-MPMI was developed by the team led by David E. Nichols from Purdue University in the late 1990s.

04Society and culture

Legal status

Canada

4-HO-MPMI is not a controlled substance in Canada as of 2025.

Watch videos about 4-HO-MPMIExplainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article “4-HO-MPMI”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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Related topics

Pyrrolidinylmethylindole

Pyrrolidinylmethylindoles, or 3--1H-indoles, also known as α,N-trimethylenetryptamines, are a group of cyclized tryptamines in which the amine has been cyclized with the α position of the ethyl side chain via a propyl group to form a pyrrolidine ring. They include the psychedelic and related compounds MPMI, 4-HO-MPMI (lucigenol), 5-F-MPMI, and 5-MeO-MPMI and the triptans and related compounds eletriptan and CP-135807.

Substituted tryptamine

Substituted tryptamines, or simply tryptamines, also known as serotonin analogues, are organic compounds which may be thought of as being derived from tryptamine itself. The molecular structures of all tryptamines contain an indole ring system, joined to an amino (NH2) group via an ethyl (−CH2-CH2−) sidechain.

MSP-2020

MSP-2020 is a psychedelic drug of the tryptamine and pyrrolidinylmethylindole families related to psilocybin which is under development for the treatment of mental disorders such as major depressive disorder. It is taken orally.