Harmane

Harmane, or harman, also known as 1-methyl-β-carboline, is a heterocyclic amine and β-carboline found in a variety of foods including coffee,^[1] sauces,^[2] and cooked meat.^[3] It is also present in tobacco smoke.^[4]

Harmane

Names
Preferred IUPAC name 1-Methyl-9H-pyrido[3,4-b]indole
Other names Harman, 1-Methyl-β-carboline, Aribine, Aribin, Locuturine, Locuturin, Loturine, Passiflorin, 1-Methylnorharman, NSC 54439
Identifiers
CAS Number	486-84-0 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:5623
ChemSpider	4444755
ECHA InfoCard	100.006.948
EC Number	207-642-2
KEGG	C09209
PubChem CID	5281404
UNII	82D6J0535P Y
CompTox Dashboard (EPA)	DTXSID80197568
InChI InChI=1S/C12H10N2/c1-8-12-10(6-7-13-8)9-4-2-3-5-11(9)14-12/h2-7,14H,1H3 Key: PSFDQSOCUJVVGF-UHFFFAOYSA-N InChI=1/C12H10N2/c1-8-12-10(6-7-13-8)9-4-2-3-5-11(9)14-12/h2-7,14H,1H3 Key: PSFDQSOCUJVVGF-UHFFFAOYAA
SMILES CC1=NC=CC2=C1NC3=CC=CC=C23
Properties
Chemical formula	C12H10N2
Molar mass	182.226 g·mol−1
Melting point	235–238 °C (455–460 °F; 508–511 K)
Solubility in water	Soluble to 10 mM in 1 eq. HCl methanol: soluble 50 mg/ml
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Harmane is related to other alkaloids, harmine and harmaline, found in 1837 in the plant Peganum harmala.^[5] The name derives from the Arabic word for the plant, حَرْمَل (ḥarmal).

In humans, harmane is a potent tremor-producing neurotoxin.^[6] Harmane has been found to inhibit the early stages of the growth of the malaria parasite in the gut of mosquitoes infected by the bacterium Delftia tsuruhatensis, and can be absorbed by the mosquitoes upon contact.^[7][8][9]

Pharmacology

Harmane fails to substitute for the psychedelic drug DOM in rodent drug discrimination tests.^[10] This is similar to the case of harmine but is in contrast to harmaline and 6-methoxyharmalan.^[10]

Chemistry

Harmane is a methylated derivative of β-carboline with the molecular formula C₁₂H₁₀N₂.

Natural occurrence

Plant sources

Family	Plant
Rubiaceae	Coffea arabica[1]
Solanaceae	Nicotiana tabacum[11]
Theaceae	Camellia sinensis[12]

In 1962, Poindexter et al. found that there was very little harmane in tobacco, but a significant amount in tobacco smoke. They showed that it is produced from tryptophan by the heat of burning the tobacco.^[11]

See also

• Substituted β-carboline
• Harmine