Harmaline

Harmaline
Clinical data
Other names	7-Methoxyharmalan; 7-MeO-harmalan; 7-OMe-harmalan; 3,4-Dihydroharmine; 3,4-Dihydro-7-methoxy-1-methyl-β-carboline; Harmadine
Routes of; administration	Oral
Legal status
Legal status	AU: S9 (Prohibited substance); CA: Schedule III;
Identifiers
	IUPAC name 7-methoxy-1-methyl-4,9-dihydro-3H-pyrido[3,4-b]indole;
CAS Number	304-21-2 ;
PubChem CID	5280951;
ChemSpider	10211258 ;
UNII	CN58I4TOET;
KEGG	C06536 ;
ChEBI	CHEBI:28172 ;
ChEMBL	ChEMBL340807 ;
CompTox Dashboard (EPA)	DTXSID8041038 ;
ECHA InfoCard	100.005.594
Chemical and physical data
Formula	C13H14N2O
Molar mass	214.268 g·mol−1
3D model (JSmol)	Interactive image;
Melting point	232–234 °C (450–453 °F)
	SMILES COc3ccc2c1CCN=C(C)c1[nH]c2c3;
	InChI InChI=1S/C13H14N2O/c1-8-13-11(5-6-14-8)10-4-3-9(16-2)7-12(10)15-13/h3-4,7,15H,5-6H2,1-2H3 ; Key:RERZNCLIYCABFS-UHFFFAOYSA-N ;
	(verify)

Harmaline, also known as 7-methoxyharmalan or as 3,4-dihydro-7-methoxy-1-methyl-β-carboline, is a fluorescent indole alkaloid from the group of harmala alkaloids and β-carbolines.^[1]^[2]^[3] It is the partly hydrogenated form of harmine. It is a reversible monoamine oxidase inhibitor (RIMA). It produces vivid dream-like visual effects and physical discomfort at oral doses of 300 to 400 mg, often leading users to seek solitude in a quiet, dark environment.^[2]^[3]

Plants containing harmaline are combined in ayahuasca to inhibit monoamine oxidase, allowing orally ingested DMT to remain active in the brain and produce psychoactive effects. Harmala alkaloids, including harmaline, are psychoactive on their own in humans, with harmaline being particularly hallucinogenic, although other compounds such as harmine and tetrahydroharmine have also been reported to produce hallucinogenic effects as well.

Harmaline exhibits weak affinity for 5-HT_2A and 5-HT_2C receptors, partially substitutes for the psychedelic DOM in rodents, inhibits acetylcholinesterase and histamine N-methyltransferase, and stimulates dopamine release at high doses.

Harmaline is present in Peganum harmala (Syrian rue). Syrian rue seeds contain about 3% harmala alkaloids by dry weight. Harmaline was first isolated from plants in 1841, its chemical structure identified in 1919, and it was first synthesized in 1927.

^ Brimblecombe RW, Pinder RM (1975). "Indolealkylamines and Related Compounds". Hallucinogenic Agents. Bristol: Wright-Scientechnica. pp. 98–144. ISBN 978-0-85608-011-1. OCLC 2176880. OL 4850660M. [...] the apparent superiority of extracts of Banisteriopsis over the pure harmine prompted the suggestion (Hochstein and Paradies, 1957) that either harmaline or 1,2,3,4-tetrahydroharmine, or other as then unidentified constituents, were the psychoactive compounds. Naranjo (1967) has now confirmed their hallucinogenic activity in man together with that of 6-methoxyharmalan and 6-methoxytetrahydroharman. [...]
^ ^a ^b Shulgin AT (1977). "Profiles of Psychedelic Drugs: 4. Harmaline". Journal of Psychedelic Drugs. 9 (1): 79–80. doi:10.1080/02791072.1977.10472029. ISSN 0022-393X. Retrieved 11 April 2025. Close biosynthetic relatives of harmaline (harmine and tetrahydroharmine) are known components of plants of several other genera which have medical use but no reputation as hallucinogens [...] The effective dose range of harmaline in man is 70-100 mg i.v., or 300-400 mg orally. The initial effects are noted about one hour following oral administration and persist for about 6 hours [...] The indicators of physical toxicity are common and often severe. Paresthesias of hands, feet, or face are almost always present with the onset of effects, and are usually followed by the sensation of numbness. There can be isolated symptoms such as pressure in the head or chest, nausea and distressful vomiting, dizziness, and general malaise. Mydriasis and pressor effects are never seen. The anxiety and general discomfort encourages a withdrawal from social contact, and a quiet dark environment is preferred by most subjects. The modality most consistently affected by harmaline is the visual sense. There can be vivid images generated, often in the form of meaningful dream-like sequences, and frequently containing subject matter such as wild animals or jungle scenes. Other reported visual syntheses are limited to the generation of geometric patterns which are entertaining but not felt to be of any intrinsic significance.
^ ^a ^b "Erowid Online Books : "TIHKAL" - #13 HARMALINE". www.erowid.org. Retrieved 11 April 2025.

[BrimblecombePinder1975-1] Brimblecombe RW, Pinder RM (1975). "Indolealkylamines and Related Compounds". Hallucinogenic Agents. Bristol: Wright-Scientechnica. pp. 98–144. ISBN 978-0-85608-011-1. OCLC 2176880. OL 4850660M. [...] the apparent superiority of extracts of Banisteriopsis over the pure harmine prompted the suggestion (Hochstein and Paradies, 1957) that either harmaline or 1,2,3,4-tetrahydroharmine, or other as then unidentified constituents, were the psychoactive compounds. Naranjo (1967) has now confirmed their hallucinogenic activity in man together with that of 6-methoxyharmalan and 6-methoxytetrahydroharman. [...]

[Shulgin1977-2] Shulgin AT (1977). "Profiles of Psychedelic Drugs: 4. Harmaline". Journal of Psychedelic Drugs. 9 (1): 79–80. doi:10.1080/02791072.1977.10472029. ISSN 0022-393X. Retrieved 11 April 2025. Close biosynthetic relatives of harmaline (harmine and tetrahydroharmine) are known components of plants of several other genera which have medical use but no reputation as hallucinogens [...] The effective dose range of harmaline in man is 70-100 mg i.v., or 300-400 mg orally. The initial effects are noted about one hour following oral administration and persist for about 6 hours [...] The indicators of physical toxicity are common and often severe. Paresthesias of hands, feet, or face are almost always present with the onset of effects, and are usually followed by the sensation of numbness. There can be isolated symptoms such as pressure in the head or chest, nausea and distressful vomiting, dizziness, and general malaise. Mydriasis and pressor effects are never seen. The anxiety and general discomfort encourages a withdrawal from social contact, and a quiet dark environment is preferred by most subjects. The modality most consistently affected by harmaline is the visual sense. There can be vivid images generated, often in the form of meaningful dream-like sequences, and frequently containing subject matter such as wild animals or jungle scenes. Other reported visual syntheses are limited to the generation of geometric patterns which are entertaining but not felt to be of any intrinsic significance.

[TiHKAL1997-3] "Erowid Online Books : "TIHKAL" - #13 HARMALINE". www.erowid.org. Retrieved 11 April 2025.

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