6-Methoxyharman

Pharmaceutical compound From Wikipedia, the free encyclopedia

6-Methoxyharman, also known as isoharmine, is a β-carboline and harmala alkaloid.^[1]^[2]^[3]^[4]^[5] It is an analogue of other β-carbolines like harman and 6-methoxyharmalan.^[6]^[7] The compound has been found to be naturally occurring in Peganum harmala and Virola species such as Virola cuspidata and Virola elongata.^[5]^[3]^[8]^[9]^[10] It is a potent monoamine oxidase inhibitor (MAOI).^[7] In addition, 6-methoxyharman has been found to bind to serotonin receptors, including the serotonin 5-HT_2C receptor (K_i = 3,700 nM), but notably not to the serotonin 5-HT_2A or 5-HT_1A receptors (K_i = >10,000).^[11]^[12]^[13] It may potentiate the effects of psychedelic tryptamines like dimethyltryptamine (DMT) via its MAOI activity, for instance when they are used as Virola-containing hallucinogenic snuffs.^[9] According to Alexander Shulgin, Claudio Naranjo might have tested the effects 6-methoxyharman in humans, but this is unclear.^[14]^[15]

Other namesCoharmine; Isoharmine; 6-Methoxyharmane; 6-MeO-harman; 6-OMe-harman; 6-Methoxy-1-methyl-β-carboline; 1-Methyl-6-methoxy-2-carboline

ATC code

None

CAS Number

3589-72-8

PubChem CID

5376026

Quick facts Clinical data, Other names ...

6-Methoxyharman
Clinical data


Other names	Coharmine; Isoharmine; 6-Methoxyharmane; 6-MeO-harman; 6-OMe-harman; 6-Methoxy-1-methyl-β-carboline; 1-Methyl-6-methoxy-2-carboline
ATC code	None
Identifiers
IUPAC name 6-methoxy-1-methyl-9H-pyrido[3,4-b]indole
CAS Number	3589-72-8
PubChem CID	5376026
ChemSpider	4525389
UNII	48GQI7H930
ChEMBL	ChEMBL278193
CompTox Dashboard (EPA)	DTXSID40189449
Chemical and physical data
Formula	C₁₃H₁₂N₂O
Molar mass	212.252 g·mol⁻¹
3D model (JSmol)	Interactive image
SMILES CC1=NC=CC2=C1NC3=C2C=C(C=C3)OC
InChI InChI=1S/C13H12N2O/c1-8-13-10(5-6-14-8)11-7-9(16-2)3-4-12(11)15-13/h3-7,15H,1-2H3 Key:XYYVPBBISSKKQB-UHFFFAOYSA-N

References

[1]
Shulgin AT (1969). "Psychotomimetic Agents Related to the Catecholamines". Journal of Psychedelic Drugs. 2 (2): 14–19. doi:10.1080/02791072.1969.10524409. ISSN 0022-393X. Archived from the original on 2025-07-12. A closer relationship may be seen with the alkaloids of the Harmala group, such as harmaline (VIa; Figure 4). This material along with its dehydro- and dihydro- counterparts (harmine and leptaflorine) are found in a number of intoxicating plants. It could be argued that they are generated through the cyclization of a positional isomer of serotonin (6-hydroxytryptamine) with some two-carbon compound. More intriguing are the isomers of marmaline wherein the methoxyl group is relocated to the position entirely analogous to serotonin. This material is 6-methoxyharmalan (Vib; Figure 4), and its dehydro- and dihydro- counterparts (6-methoxyharman and 6-methoxytetrahydroharman) are all several times more potent than the 7-methoxy compounds.
[2]
Shulgin AT (1972). "Hallucinogens, CNS Stimulants, And Cannabis". In Mule SJ, Brill H (eds.). Chemical and Biological Aspects of Drug Dependence. CRC Press. pp. 163–176. doi:10.1201/9780429260629-16. ISBN 978-0-87819-011-9. The Virola snuffs of northern South America have long been associated with the Piptadenia group of intoxicants known as Yaje. Although origiJ1ally thought to be related to nutmeg, these are now known to contain alkaloids. I 6 These are positional isomers of the harmaline series and are more potent. Here, the major alkaloid is the tetrahydro isomer I 7 (Figure 7, RI = CH3 , R2 = H), but the two dehydrogenation products (6-methoxyharmalan and 6-methoxyharman, Figure 7, with one and two double bonds in the pyridine ring) are clearly present. IS
[3]
Singh Saroya A, Singh J (2020). "Description of Psychoactive Medicinal Plants". Psychoactive Medicinal Plants and Fungal Neurotoxins. Singapore: Springer Singapore. pp. 15–106. doi:10.1007/978-981-15-2313-7_3. ISBN 978-981-15-2312-0. Retrieved 14 October 2025. Virola cuspidata Warb. Distribution: Native to Central America. Botanical description: A tree. Phytochemistry: Alkaloids (dimethyltryptamine, 6-methoxyharmalan and 6-methoxyharman (Cassady et al. 1971), and (Z)-3,5,4′-trimethoxystilbene) (Chabert et al. 2006) (Fig. 3.114 and 3.115).
[4]
Glennon RA, Rosecrans JA (1982). "Indolealkylamine and phenalkylamine hallucinogens: a brief overview". Neuroscience and Biobehavioral Reviews. 6 (4): 489–497. doi:10.1016/0149-7634(82)90030-6. PMID 6757811. (6) β-Carbolines: Several β-carboline derivatives have been isolated from plant sources (e.g., harmine, 6a; harmaline, 6b), and other molecular modifications have been prepared synthetically (e.g., 6-methoxyharman, 6c; 6-methoxyharmalan, 6d) (Fig. 1). Most of the human data on these compounds is from a study by Naranjo [50]. While these compounds are active in man, none has been found to be significantly more potent than DMT (3a).
[5]
Ayoub MT, Rashan L (1991). "Isoharmine, a β-carboline alkaloid from Peganum harmala seeds". Phytochemistry. 30 (3): 1046–1047. Bibcode:1991PChem..30.1046A. doi:10.1016/0031-9422(91)85312-N. Retrieved 14 October 2025.
[6]
Shulgin A, Shulgin A (September 1997). TiHKAL: The Continuation. Berkeley, California: Transform Press. ISBN 0-9630096-9-9. OCLC 38503252. "6-MEO-THH".
[7]
McKenna DJ (1984). Monoamine oxidase inhibitors in Amazonian hallucinogenic plants : ethnobotanical, phytochemical, and pharmacological investigations. University of British Columbia (Thesis). doi:10.14288/1.0096656. Retrieved 14 October 2025.
[8]
González-Rodríguez M, Ruiz-Fernández C, Francisco V, Ait Eldjoudi D, Farrag AbdElHafez YR, Cordero-Barreal A, et al. (February 2021). "Pharmacological Extracts and Molecules from Virola Species: Traditional Uses, Phytochemistry, and Biological Activity". Molecules. 26 (4): 792. doi:10.3390/molecules26040792. PMC 7913652. PMID 33546469. The β-carbolines 6-methoxyharmalan and 6-methoxyharman, which have been suggested to possess some psychoactive effects, have also been isolated from V. elongata [19].
[9]
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. Nevertheless, they are the minor alkaloids in Virola species, from which are made hallucinogenic snuffs such as Yakee, Parica, and Epena, and whose major alkaloids are various tryptamines (Agurell, Holmstedt, Lindgren, and Schultes, 1968, 1969; Cassady, Blair, Raffauf, and Tyler, 1971). It is probable that such compounds as 6-methoxyharmalan (4.32), 6-methoxyharman (4.33), and 6-methoxytetrahydroharman (4.34) potentiate the central actions of these tryptamines by their inhibition of monoarnine oxidase.
[10]
Cassady JM, Blair GE, Raffauf RF, Tyler VE (March 1971). "The isolation of 6-methoxyharmalan and 6-methoxyharman from Virola cuspidata". Lloydia. 34 (1): 161–162. PMID 5140263.
[11]
Glennon RA (August 1981). "Serotonin receptor interactions of harmaline and several related beta-carbolines". Life Sciences. 29 (8): 861–865. doi:10.1016/0024-3205(81)90043-6. PMID 7300579.
[12]
Grella B, Dukat M, Young R, Teitler M, Herrick-Davis K, Gauthier CB, et al. (April 1998). "Investigation of hallucinogenic and related beta-carbolines". Drug and Alcohol Dependence. 50 (2): 99–107. doi:10.1016/s0376-8716(97)00163-4. PMID 9649961.
[13]
Glennon RA, Dukat M, Grella B, Hong S, Costantino L, Teitler M, et al. (August 2000). "Binding of beta-carbolines and related agents at serotonin (5-HT(2) and 5-HT(1A)), dopamine (D(2)) and benzodiazepine receptors". Drug and Alcohol Dependence. 60 (2): 121–132. doi:10.1016/s0376-8716(99)00148-9. hdl:11380/17721. PMID 10940539.
[14]
Shulgin AT (1976). "Psychotomimetic Agents". In Gordon M (ed.). Psychopharmacological Agents: Use, Misuse and Abuse. Medicinal Chemistry: A Series of Monographs. Vol. 4. Academic Press. pp. 59–146. doi:10.1016/b978-0-12-290559-9.50011-9. ISBN 978-0-12-290559-9. In the analogous 6-methoxyharman series, Naranjo has reported the analog of harmaline, 6-methoxyharmalan (XL VI) to be orally active with threshold effects noted at oral levels of 1.5 mg/kg. The same levels of the tetrahydro counterpart, 6-methoxytetrahydroharman (XL VII) led to "mild effects." It is uncertain if the totally aromatic analog, 6-methoxyharman, was evaluated. The psychic changes associated with the most thoroughly studied member of this series, harmaline, have been discussed at length (Naranjo, 1969) and compared with several other pharmacologically related psychotomimetic drugs (Naranjo, 1973).
[15]
Naranjo C (1969). "Psycotherapeutic Possibilities of New Fantasy-Enhancing Drugs". Clinical Toxicology. 2 (2): 209–224. doi:10.3109/15563656908990930. ISSN 0009-9309. Retrieved 14 October 2025.

6-Methoxyharman

See also

References

External links

Related Articles