Pyrrolidinylethylindole

Pyrrolidinylethylindoles, or 3-(2-pyrrolidinylethyl)indoles, also known as pyr-tryptamines or N,N-tetramethylenetryptamines, are a group of cyclized tryptamines in which the amine has been replaced with or cyclized into a pyrrolidine ring. They can also be thought of as derivatives of the psychedelic tryptamine N,N-diethyltryptamine (DET) in which the ethyl groups attached to the amine have been connected together to form a ring. Examples of pyrrolidinylethylindoles include pyr-T, 4-HO-pyr-T, 5-MeO-pyr-T, and 4-F-5-MeO-pyr-T.

Pyrrolidinylethylindoles are known to act as serotonin receptor agonists, primarily of the serotonin 5-HT_1A receptor and to variably lesser extents of the serotonin 5-HT_2A receptor. In addition, they are known to be psychoactive drugs and some have psychedelic-like effects, although they are very different in their subjective effects compared to other psychedelic tryptamines. ^{[1] [2] [3] [4] [5] [6] [7] [8] [9] [10]}

Chemical structures of selected pyrrolidinylethylindoles

• 
  Pyr-T
• 
  4-HO-pyr-T
• 
  5-MeO-pyr-T
• 
  4-F-5-MeO-pyr-T

See also

• Cyclized tryptamine
• Pyrrolidinylmethylindole
• Pip-Tryptamine

References

1. Shulgin, Alexander; Shulgin, Ann (September 1997). TiHKAL: The Continuation. Berkeley, California: Transform Press. ISBN   0-9630096-9-9. OCLC   38503252.
2. Shulgin AT (2003). "Basic Pharmacology and Effects". In Laing RR (ed.). Hallucinogens: A Forensic Drug Handbook. Forensic Drug Handbook Series. Elsevier Science. pp. 67–137. ISBN   978-0-12-433951-4 . Retrieved 1 February 2025.
3. 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 cyclic analogue of DET, 3-(2-pyrrolidinoethyl)indole (4.13), was as active as the parent compound in behavioural tests in rodents, cats, and primates (Brimblecombe, 1967; Hunt and Brimblecombe, 1967; Brad Icy and Johnston, 1970). The compound was effective at doses down to 0·5 mg./kg. (s.c.) in disrupting the ability of monkeys to perform learned responses, but it is active only at levels which approach its lethal dose and it is unlikely to be tested in man. [...] Compounds of interest which have not been tested in man include [...] 5-methoxy-3-(2-pyrrolidinoethyl)indole, which is the most potent tryptamine so far revealed by the open field test, though its high toxicity will preclude tests in man (Brimblecombe, 1967; Hunt and Brimblecombe, 1967).
4. Nichols DE (2018). "Chemistry and Structure-Activity Relationships of Psychedelics". Current Topics in Behavioral Neurosciences. Vol. 36. pp. 1–43. doi:10.1007/7854_2017_475. ISBN   978-3-662-55878-2. PMID   28401524. Tethering the dialkyl groups into a heterocyclic ring gave mixed results; N-pyrrolidyl had an affinity similar to N,N-dimethyltryptamine (110 vs. 75 nM, respectively), but the affinity for the N-piperidyl was much lower, at 760 nM.
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8. Puigseslloses P, Islam MN, Ketsela G, Holy M, Niello M, Berzosa X, Camarasa J, Pubill D, Sitte H, Escubedo E, López-Arnau R, Nadal-Gratacós N (2023). "5-MeO-MET, 5-MeO-DET and 5-MeO-pyr-T strongly bind to 5-HT1A and 5-HT2A receptors and act as partial SERT substrates". Neuroscience Applied. 2 103724. doi: 10.1016/j.nsa.2023.103724 .
9. Laban U, Kurrasch-Orbaugh D, Marona-Lewicka D, Nichols DE (March 2001). "A novel fluorinated tryptamine with highly potent serotonin 5-HT1A receptor agonist properties". Bioorganic & Medicinal Chemistry Letters. 11 (6): 793–795. doi:10.1016/s0960-894x(01)00062-2. PMID   11277522.
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