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  • 7-methoxy-1-methyl-4,9-dihydro-3H-pyrido[3,4-b]indole
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Formula C13H14N2O
Molar mass 214.268 g·mol−1
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Melting point 232–234 °C (450–453 °F)
  • COc3ccc2c1CCN=C(C)c1[nH]c2c3
  • 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 Yes check.svgY
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Harmaline is a fluorescent indole alkaloid from the group of harmala alkaloids and beta-carbolines. It is the partly hydrogenated form of harmine.


Occurrence in nature

Various plants contain harmaline including Peganum harmala (Syrian rue) as well as the hallucinogenic beverage ayahuasca, which is traditionally brewed using Banisteriopsis caapi . Present at 3% by dry weight, the harmala alkaloids may be extracted from the Syrian rue seeds. [1]


Harmaline is a central nervous system stimulant and a "reversible inhibitor of MAO-A (RIMA)". [2] This means that the risk of a hypertensive crisis, a dangerous high blood pressure crisis from eating tyramine-rich foods such as cheese, is likely lower with harmaline than with irreversible MAOIs such as phenelzine.

Harmaline and harmine fluoresce under ultraviolet light. These three extractions indicate that the middle one has a higher concentration of the two compounds. Harmaline Harmine.jpg
Harmaline and harmine fluoresce under ultraviolet light. These three extractions indicate that the middle one has a higher concentration of the two compounds.

The harmala alkaloids are psychoactive in humans. [1] Harmaline is shown to act as an acetylcholinesterase inhibitor. [3] Harmaline also stimulates striatal dopamine release in rats at very high dose levels. [4] Since harmaline is a reversible inhibitor of monoamine oxidase A, it could, in theory, induce both serotonin syndrome and hypertensive crises in combination with tyramine, serotonergics, catecholaminergics drugs or prodrugs. Harmaline-containing plants and tryptamine-containing plants are used in ayahuasca brews. The inhibitory effects on monoamine oxidase allows dimethyltryptamine (DMT), the psychoactively prominent chemical in the mixture, to bypass the extensive first-pass metabolism it undergoes upon ingestion, allowing a psychologically active quantity of the chemical to exist in the brain for a perceivable period of time. [5] Harmaline forces the anabolic metabolism of serotonin into N-acetylserotonin (normelatonin), and then to melatonin, the body's principal sleep-regulating hormone and a powerful antioxidant.

United States Patent Number 5591738 describes a method for treating various chemical dependencies via the administration of harmaline and or other beta-carbolines. [6]

A study has reported the antiviral activity of Harmaline against Herpes Simplex Virus 1 and 2 (HSV-1 and HSV-2) by inhibiting immediate early transcription of the virus at noncytotoxic concentration. [7]

Harmaline is known to act as a histamine N-methyltransferase inhibitor. [8] This explains how harmaline elicits its wakefulness-promoting effects.


Harmala alkaloids are considered Schedule 9 prohibited substances under the Poisons Standard (October 2015). [9] A Schedule 9 substance is a substance which may be abused or misused, the manufacture, possession, sale or use of which should be prohibited by law except when required for medical or scientific research, or for analytical, teaching or training purposes with approval of Commonwealth and/or State or Territory Health Authorities. [9]


Harmaline and Harmalol are considered Schedule III controlled substances by the Controlled Drugs and Substances Act. Every person found to be in possession of a Schedule III drug is guilty of an indictable offence and liable to imprisonment for a term not exceeding three years; or for a first offence, guilty on summary conviction, to a fine not exceeding one thousand dollars or to imprisonment for a term not exceeding six months, or to both. Every person found to be trafficking a Schedule III drug is guilty of an indictable offence and liable to imprisonment for a term not exceeding ten years, or is guilty on summary conviction (first-time offenders) and liable to imprisonment for a term not exceeding eighteen months. [10]

See also

Related Research Articles

<span class="mw-page-title-main">Ayahuasca</span> South American psychoactive brew

Ayahuasca is a South American psychoactive and entheogenic brewed drink traditionally used both socially and as a ceremonial or shamanic spiritual medicine among the indigenous peoples of the Amazon basin, and more recently in Western society. The tea causes altered states of consciousness often known as "psychedelic experiences" which include visual hallucinations and altered perceptions of reality.

<i>N</i>,<i>N</i>-Dimethyltryptamine Chemical compound

N,N-Dimethyltryptamine is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a psychedelic drug and prepared by various cultures for ritual purposes as an entheogen.

<i>alpha</i>-Methyltryptamine Chemical compound

α-Methyltryptamine is a psychedelic, stimulant, and entactogen drug of the tryptamine class. It was originally developed as an antidepressant by workers at Upjohn in the 1960s, and was used briefly as an antidepressant in Russia under the trade name Indopan before being discontinued.

<i>Banisteriopsis caapi</i> Species of plant

Banisteriopsis caapi, also known as, caapi, soul vine, or yagé (yage), is a South American liana of the family Malpighiaceae. It is commonly used as an ingredient of ayahuasca, a decoction with a long history of its entheogenic use and its status as a "plant teacher" among the Indigenous peoples of the Amazon rainforest.

<i>beta</i>-Carboline Chemical compound also known as norharmane

β-Carboline (9H-pyrido[3,4-b]indole) represents the basic chemical structure for more than one hundred alkaloids and synthetic compounds. The effects of these substances depend on their respective substituent. Natural β-carbolines primarily influence brain functions but can also exhibit antioxidant effects. Synthetically designed β-carboline derivatives have recently been shown to have neuroprotective, cognitive enhancing and anti-cancer properties.

<span class="mw-page-title-main">Harmala alkaloid</span> Group of chemical compounds

Several alkaloids that function as monoamine oxidase inhibitors (MAOIs) are found in the seeds of Peganum harmala, as well as tobacco leaves including harmine, harmaline, and harmalol, which are members of a group of substances with a similar chemical structure collectively known as harmala alkaloids. These alkaloids are of interest for their use in Amazonian shamanism, where they are derived from other plants. The harmala alkaloid harmine, once known as telepathine and banisterine, is a naturally occurring beta-carboline alkaloid that is structurally related to harmaline, and also found in the vine Banisteriopsis caapi. Tetrahydroharmine is also found in B. caapi and P. harmala. Dr. Alexander Shulgin has suggested that harmine may be a breakdown product of harmaline. Harmine and harmaline are both a reversible inhibitor of monoamine oxidase A (RIMAs). They can stimulate the central nervous system by inhibiting the metabolism of monoamine compounds such as serotonin and norepinephrine.

<i>Peganum harmala</i> Species of plant

Peganum harmala, commonly called wild rue, Syrian rue, African rue, esfand or espand, or harmel, is a perennial, herbaceous plant, with a woody underground rootstock, of the family Nitrariaceae, usually growing in saline soils in temperate desert and Mediterranean regions. Its common English-language name came about because of a resemblance to rue. Because eating it can cause livestock to sicken or die, it is considered a noxious weed in a number of countries. It has become an invasive species in some regions of the western United States. The plant is popular in Middle Eastern and north African folk medicine. The alkaloids contained in the plant, including the seeds, are monoamine oxidase inhibitors.

<span class="mw-page-title-main">Diethyltryptamine</span> Chemical compound

DET, also known under its chemical name N,N-diethyltryptamine and as T-9, is a psychedelic drug closely related to DMT and 4-HO-DET. However, despite its structural similarity to DMT, its activity is induced by an oral dose of around 50–100 mg, without the aid of MAO inhibitors, and the effects last for about 2–4 hours.

Harmine is a beta-carboline and a harmala alkaloid. It occurs in a number of different plants, most notably the Syrian rue and Banisteriopsis caapi. Harmine reversibly inhibits monoamine oxidase A (MAO-A), an enzyme which breaks down monoamines, making it a Reversible inhibitor of monoamine oxidase A (RIMA). Harmine does not inhibit MAO-B. Harmine is also known as banisterin, banisterine, telopathin, telepathine, leucoharmine and yagin, yageine.

<span class="mw-page-title-main">Tetrahydroharmine</span>

Tetrahydroharmine (THH) is a fluorescent indole alkaloid that occurs in the tropical liana species Banisteriopsis caapi.

Pharmahuasca is a pharmaceutical version of the entheogenic brew ayahuasca. Traditional ayahuasca is made by brewing the MAOI-containing Banisteriopsis caapi vine with a DMT-containing plant, such as Psychotria viridis. Pharmahuasca refers to a similar combination that uses a pharmaceutical MAOI instead of a plant.

<span class="mw-page-title-main">Dopaminergic</span> Substance related to dopamine functions

Dopaminergic means "related to dopamine" (literally, "working on dopamine"), dopamine being a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain. Dopaminergic brain pathways facilitate dopamine-related activity. For example, certain proteins such as the dopamine transporter (DAT), vesicular monoamine transporter 2 (VMAT2), and dopamine receptors can be classified as dopaminergic, and neurons that synthesize or contain dopamine and synapses with dopamine receptors in them may also be labeled as dopaminergic. Enzymes that regulate the biosynthesis or metabolism of dopamine such as aromatic L-amino acid decarboxylase or DOPA decarboxylase, monoamine oxidase (MAO), and catechol O-methyl transferase (COMT) may be referred to as dopaminergic as well. Also, any endogenous or exogenous chemical substance that acts to affect dopamine receptors or dopamine release through indirect actions (for example, on neurons that synapse onto neurons that release dopamine or express dopamine receptors) can also be said to have dopaminergic effects, two prominent examples being opioids, which enhance dopamine release indirectly in the reward pathways, and some substituted amphetamines, which enhance dopamine release directly by binding to and inhibiting VMAT2.

<i>N</i>-Methyltryptamine Chemical compound

N-Methyltryptamine (NMT) is a member of the substituted tryptamine chemical class and a natural product which is biosynthesized in the human body from tryptamine by certain N-methyltransferase enzymes, such as indolethylamine N-methyltransferase. It is a common component in human urine. NMT is an alkaloid derived from L-tryptophan that has been found in the bark, shoots and leaves of several plant genera, including Virola, Acacia, Mimosa, and Desmanthus—often together with the related compounds N,N-dimethyltryptamine (DMT) and 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT).

<i>Psychotria carthagenensis</i> Species of plant

Psychotria carthagenensis, also known as amyruca, is a South American rainforest understory shrub from the coffee family, Rubiaceae. It grows from the tropics of South America to Mexico.

<span class="mw-page-title-main">Harmalol</span> Chemical compound

Harmalol is a bioactive beta-carboline and a member of the harmala alkaloids.

<span class="mw-page-title-main">Tetrahydroharmol</span> Chemical compound

Tetrahydroharmol is a bioactive beta-carboline harmala alkaloid. It acts as a reversible inhibitor of monoamine oxidase A.

<span class="mw-page-title-main">Indole alkaloid</span> Class of alkaloids

Indole alkaloids are a class of alkaloids containing a structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known different compounds, it is one of the largest classes of alkaloids. Many of them possess significant physiological activity and some of them are used in medicine. The amino acid tryptophan is the biochemical precursor of indole alkaloids.

<span class="mw-page-title-main">Harmol</span> Chemical compound

Harmol is a chemical compound classified as a β-carboline. It is readily formed in vivo in humans by O-demethylation of harmine.

<span class="mw-page-title-main">Changa (drug)</span> DMT-infused smoking blend

Changa is a blend of N,N-Dimethyltryptamine (DMT) mixed with a monoamine oxidase inhibitor (MAOI). The addition of MAOIs extend the DMT experience in duration and intensity when compared with smoking DMT freebase alone. Typically, extracts from DMT-containing plants are combined with a blend of different MAOI-containing herbs, such as the ayahuasca vine, and/or leaf or harmala alkaloids from Peganum harmala to create a mix that is 25 to 50% DMT.


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  3. Zheng XY, Zhang ZJ, Chou GX, Wu T, Cheng XM, Wang CH, Wang ZT (September 2009). "Acetylcholinesterase inhibitive activity-guided isolation of two new alkaloids from seeds of Peganum nigellastrum Bunge by an in vitro TLC- bioautographic assay". Archives of Pharmacal Research. 32 (9): 1245–51. doi:10.1007/s12272-009-1910-x. PMID   19784581. S2CID   1218229.
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