Article · Wikipedia archive · Last revised Jun 30, 2026

Medmain

Medmain, also known as 2-methyl-3-ethyl-5-dimethylaminoindole, is a serotonin receptor modulator, convulsant, and indole derivative related to the neurotransmitter serotonin. It has low-potency serotonin antagonist or partial agonist activity, with low affinity for serotonin 5-HT1 and 5-HT2 receptors (IC50Tooltip half-maximal inhibitory concentration = >1,000 nM) but greater activity against the serotonin receptors in the rat stomach fundus strip (KB = 50 nM) (thought to represent the serotonin 5-HT2B receptor). Owing to its convulsant activity, medmain was tested in animals but not in humans. The drug was described and studied by E. Shaw and Dilworth Woolley in the 1950s. A derivative, 1-methylmedmain, is also known, and has similar potency as a serotonin antagonist but lacks the convulsant activity of medmain. Other analogues of medmain have been explored as well, but none had improved activity at the rat fundus strip serotonin 5-HT2B receptor compared to medmain and 1-methylmedmain.

Last revised
Jun 30, 2026
Read time
≈ 2 min
Length
356 w
Citations
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Source
Wikipedia ↗
Medmain
Clinical data
Other names2-Methyl-3-ethyl-5-dimethylaminoindole
Drug classSerotonin receptor modulator; Serotonin antagonist or partial agonist; Convulsant
ATC code
  • None
Identifiers
  • 3-ethyl-N,N,2-trimethyl-1H-indol-5-amine
CAS Number
PubChem CID
ChemSpider
UNII
ChEMBL
CompTox Dashboard (EPA)
Chemical and physical data
FormulaC13H18N2
Molar mass202.301 g·mol−1
3D model (JSmol)
  • CCC1=C(NC2=C1C=C(C=C2)N(C)C)C
  • InChI=1S/C13H18N2/c1-5-11-9(2)14-13-7-6-10(15(3)4)8-12(11)13/h6-8,14H,5H2,1-4H3
  • Key:IOYNGCZNYGEZRO-UHFFFAOYSA-N

Medmain, also known as 2-methyl-3-ethyl-5-dimethylaminoindole, is a serotonin receptor modulator, convulsant, and indole derivative related to the neurotransmitter serotonin.1234 It has low-potency serotonin antagonist or partial agonist activity, with low affinity for serotonin 5-HT1 and 5-HT2 receptors (IC50Tooltip half-maximal inhibitory concentration = >1,000 nM) but greater activity against the serotonin receptors in the rat stomach fundus strip (KB = 50 nM) (thought to represent the serotonin 5-HT2B receptor).452 Owing to its convulsant activity, medmain was tested in animals but not in humans.3 The drug was described and studied by E. Shaw and Dilworth Woolley in the 1950s.423 A derivative, 1-methylmedmain, is also known, and has similar potency as a serotonin antagonist but lacks the convulsant activity of medmain.346 Other analogues of medmain have been explored as well, but none had improved activity at the rat fundus strip serotonin 5-HT2B receptor compared to medmain and 1-methylmedmain.45

References

References

  1. Usdin E, Efron DH (1972). Psychotropic Drugs and Related Compounds. National Institute of Mental Health. Retrieved 8 April 2026.
  2. Shaw E, Woolley DW (May 1954). "Pharmacological properties of some antimetabolites of serotonin having unusually high activity on isolated tissues". The Journal of Pharmacology and Experimental Therapeutics. 111 (1): 43–53. doi:10.1016/S0022-3565(25)11181-6. PMID 13163844.
  3. Woolley DW, Shaw E (July 1954). "Some neurophysiological aspects of serotonin". British Medical Journal. 2 (4880): 122–126. doi:10.1136/bmj.2.4880.122. PMC 2079253. PMID 13172487.
  4. Fludzinski P, Wittenauer LA, Schenck KW, Cohen ML (November 1986). "2,3-Dialkyl(dimethylamino)indoles: interaction with 5HT1, 5HT2, and rat stomach fundal serotonin receptors". Journal of Medicinal Chemistry. 29 (11): 2415–2418. doi:10.1021/jm00161a048. PMID 3783602.
  5. Audia JE, Evrard DA, Murdoch GR, Droste JJ, Nissen JS, Schenck KW, et al. (July 1996). "Potent, selective tetrahydro-beta-carboline antagonists of the serotonin 2B (5HT2B) contractile receptor in the rat stomach fundus". Journal of Medicinal Chemistry. 39 (14): 2773–2780. doi:10.1021/jm960062t. PMID 8709108. However, SAR data has been published for the 2-methyl-3-ethyl-5- (dimethylamino)indole ("medmain") series of 5HT2B ("fundal") receptor antagonists, from which the indolylureas were derived.20
  6. "3-ethyl-N,N,1,2-tetramethylindol-5-amine". PubChem. Retrieved 8 April 2026.