2,5-Dimethoxy-4-propylamphetamine

{{Short description|Psychedelic drug}} {{Drugbox | Verifiedfields = verified | Watchedfields = verified | verifiedrevid = 477211774 | drug_name = DOPR | image = DOPR chemical structure.svg | image_class = skin-invert-image | width = 250px | image2 = DOPR-3d-sticks.png | image_class2 = bg-transparent | width2 = 225px

| legal_CA = Schedule I | legal_DE = NpSG | legal_UK = Class A | legal_status =

| CAS_number_Ref = {{cascite|correct|CAS}} | CAS_number = 63779-88-4 | CAS_supplemental = 53581-55-8 (hydrochloride) | UNII_Ref = {{fdacite|correct|FDA}} | UNII = L3P287BI9W | PubChem = 542051 | DrugBank_Ref = {{drugbankcite|correct|drugbank}} | DrugBank = | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 472021 | ChEMBL_Ref = {{ebicite|correct|EBI}} | ChEMBL = 8569 | synonyms = 2,5-Dimethoxy-4-propylamphetamine; 4-Propyl-2,5-dimethoxyamphetamine; DOPR; DOPr

| IUPAC_name = 1-(2,5-dimethoxy-4-propylphenyl)propan-2-amine | C=14 | H=23 | N=1 | O=2 | SMILES = CCCC1=CC(=C(C=C1OC)CC(C)N)OC | StdInChI_Ref = {{stdinchicite|changed|chemspider}} | StdInChI = 1S/C15H25NO2/c1-5-6-11-8-14(17-4)12(7-10(2)15)9-13(11)16-3/h8-10H,5-7,15H2,1-4H3 | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = UEEAUFJYLUJWQJ-UHFFFAOYSA-N }}

'''2,5-Dimethoxy-4-propylamphetamine''' ('''DOPR''') is a psychedelic drug of the phenethylamine, amphetamine, and DOx families related to DOM.<ref name="PiHKAL">{{cite book | title = PiHKAL: A Chemical Love Story | vauthors = Shulgin A, Shulgin A | publisher = Transform Press | location = United States | isbn = 0-9630096-0-5 | pages = 978 | url = http://www.erowid.org/library/books_online/pihkal/pihkal.shtml |date= September 1991}}</ref><ref name="LuethiGlatfelterPottie2025">{{cite journal | vauthors = Luethi D, Glatfelter GC, Pottie E, Sellitti F, Maitland AD, Gonzalez NR, Kryszak LA, Jackson SN, Hoener MC, Stove CP, Liechti ME, Smieško M, Baumann MH, Simmler LD, Rudin D | title = The 4-alkyl chain length of 2,5-dimethoxyamphetamines differentially affects in vitro serotonin receptor actions versus in vivo psychedelic-like effects | journal = Mol Psychiatry | volume = | issue = | pages = | date = November 2025 | pmid = 41193673 | doi = 10.1038/s41380-025-03325-1 | url = https://www.nature.com/articles/s41380-025-03325-1.pdf}}</ref> It is the derivative of DOM in which the methyl group at the 4 position has been replaced with a propyl group.<ref name="PiHKAL" /> The drug is taken orally.<ref name="PiHKAL" />

The drug acts as a serotonin receptor agonist, including of the serotonin 5-HT2A receptor.<ref name="LuethiGlatfelterPottie2025" /><ref name="CunninghamBockSerrano2023" /> It produces psychedelic-like effects in animals.<ref name="LuethiGlatfelterPottie2025" /><ref name="CunninghamBockSerrano2023" />

DOPR was first described in the literature by Alexander Shulgin in 1970.<ref name="US3547999">{{cite web | title=phenethylamines and their pharmacologically-acceptable salts | website=Google Patents | date=14 July 1969 | url=https://patents.google.com/patent/US3547999 | access-date=27 November 2025}}</ref> Subsequently, it was described in greater detail by Shulgin in his 1991 book ''PiHKAL'' (''Phenethylamines I Have Known and Loved'').<ref name="PiHKAL" />

==Use and effects== In his book ''PiHKAL'' (''Phenethylamines I Have Known and Loved''), Alexander Shulgin lists DOPR's dose as 2.5 to 5{{nbsp}}mg orally and its duration as 20 to 30{{nbsp}}hours.<ref name="PiHKAL" /> It is said to have a very slow onset.<ref name="PiHKAL" /> The effects of DOPR have been reported to include closed-eye imagery, visuals, thinking changes, and insomnia and sleep disruption, among others.<ref name="PiHKAL" /> In one of the reports, it was described as a "heavy duty psychedelic", including strong and unignorable visuals.<ref name="PiHKAL" />

==Interactions== {{See also|Psychedelic drug#Interactions|Trip killer#Serotonergic psychedelic antidotes}}

==Pharmacology== ===Pharmacodynamics=== DOPR acts as an agonist of the serotonin 5-HT2 receptors, including of the serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptors.<ref name="LuethiGlatfelterPottie2025" /><ref name="NobackKentonKlein2025">{{cite journal | vauthors = Noback M, Kenton JA, Klein AK, Hughes ZA, Kruegel AC, Schmid Y, Halberstadt AL, Young JW | title = Low (micro)doses of 2,5-dimethoxy-4-propylamphetamine (DOPR) increase effortful motivation in low-performing mice | journal = Neuropharmacology | volume = 268 | issue = | article-number = 110334 | date = February 2025 | pmid = 39900138 | doi = 10.1016/j.neuropharm.2025.110334 | url = | quote = According to a recent publication (Cunningham et al., 2023), DOPR acts as a potent agonist at the 5-HT2A receptor when tested in BRET assays of Gq dissociation (EC50 = 1.7 nM, Emax = 98.9% relative to 5-HT) and β-arrestin2 recruitment (EC50 = 7.96 nM, Emax = 99.8% relative to 5-HT). | doi-access = free }}</ref><ref name="NobackKentonKlein2022">{{cite journal | vauthors = Noback M, Kenton J, Klein A, Hughes Z, Kruegel A, Young J | title = ACNP 61st Annual Meeting: Poster Abstracts P541 - P809: P572. 2,5-Dimethoxy-4-Propylamphetamine (DOPR) Increased Effortful Motivation in Mice | journal = Neuropsychopharmacology | volume = 47 | issue = Suppl 1 | pages = 371–520 (390–390) | date = December 2022 | pmid = 36456695 | pmc = 9714408 | doi = 10.1038/s41386-022-01486-z | url = | quote = DOPR caused a dose-dependent increase in HTR (F(5,30)=60.0, p < 0.0001), with doses of 3.2 and 10 mg/kg passing a Bonferroni post hoc correction relative to vehicle (p < 0.002), and peak effect at 3.2 mg/kg. [...] The binding affinity at 5-HT2A of the two compounds was similar, with DOPR having a Ki of 17.56 nM and DOI having a Ki of 14.51 nM. [...] DOPR and DOI also show agonist activity at 5-HT2A (EC50 of 0.12 and 0.19 nM, respectively) and 5-HT2C (EC50 of 0.27 and 0.82 nM, respectively) receptors, with >25-fold lower potency at 5-HT2B receptors and no significant activity at 5-HT1A (both > 1,000 nM EC50). [...] The positive effect of DOPR on effortful motivation points to possible therapeutic applications in psychiatric illness states characterized by reduced effortful motivation as measured by the PRBT. The similarity of effects of DOPR to well-studied drugs such as DOI and amphetamine provides a useful reference point to interpret its pharmacological effects. Importantly, the doses needed to increase breakpoint in the PRBT were as low as 0.0106 mg/kg. While 0.1 mg/kg increased HTR, this effect was not significant, and maximal effect at 3.2 mg/kg, supporting the premise that low doses of DOPR may be therapeutic in anhedonia states without causing unwanted hallucinogenic side effects. }}</ref><ref name="CunninghamBockSerrano2023">{{cite journal |vauthors=Cunningham MJ, Bock HA, Serrano IC, Bechand B, Vidyadhara DJ, Bonniwell EM, Lankri D, Duggan P, Nazarova AL, Cao AB, Calkins MM, Khirsariya P, Hwu C, Katritch V, Chandra SS, McCorvy JD, Sames D |date=January 2023 |title=Pharmacological Mechanism of the Non-hallucinogenic 5-HT2A Agonist Ariadne and Analogs |journal=ACS Chemical Neuroscience |volume=14 |issue=1 |pages=119–135 |doi=10.1021/acschemneuro.2c00597 |pmc=10147382 |pmid=36521179 |quote=We propose the following rationale for the rapid effects of Ariadne in the mouse [Parkinson's disease (PD)] model, as an initial guiding hypothesis for future studies. The in vitro profile suggests that Ariadne’s effect on dopamine neurotransmission is indirect, namely not via direct modulation of DAT or dopamine receptors. It has been demonstrated that 5-HT2A agonists increase dopamine release in nucleus accumbens and other regions of the mesolimbic system.43 It is therefore likely that 5-HT2A agonists also stimulate DA release in more dorsal areas of the striatum that are compromised by the PD pathology.}}</ref><ref name="HemanthNistalaNguyen2023">{{cite journal | vauthors = Hemanth P, Nistala P, Nguyen VT, Eltit JM, Glennon RA, Dukat M | title = Binding and functional structure-activity similarities of 4-substituted 2,5-dimethoxyphenyl isopropylamine analogues at 5-HT2A and 5-HT2B serotonin receptors | journal = Frontiers in Pharmacology | volume = 14 | issue = | article-number = 1101290 | date = 2023 | pmid = 36762110 | pmc = 9902381 | doi = 10.3389/fphar.2023.1101290 | doi-access = free }}</ref> It has very weak affinity for the serotonin 5-HT1 receptor.<ref name="Glennon1987">{{cite journal | vauthors = Glennon RA | title = Central serotonin receptors as targets for drug research | journal = J Med Chem | volume = 30 | issue = 1 | pages = 1–12 | date = January 1987 | pmid = 3543362 | doi = 10.1021/jm00384a001 | url = | quote = Table II. Affinities of Selected Phenalkylamines for 5-HT1 and 5-HT2 Binding Sites}}</ref> The drug has also been assessed at other receptors.<ref name="LuethiGlatfelterPottie2025" />

It produces the head-twitch response (HTR), a behavioral proxy of psychedelic effects, in rodents.<ref name="LuethiGlatfelterPottie2025" /><ref name="CunninghamBockSerrano2023" /> It is slightly more potent but slightly less efficacious than DOM in producing the head-twitch response.<ref name="LuethiGlatfelterPottie2025" /> As with many other psychedelics, DOPR shows an inverted U-shaped dose–response curve in terms of the HTR, increasing it at lower doses and having diminished effectiveness at higher doses.<ref name="LuethiGlatfelterPottie2025" /><ref name="CunninghamBockSerrano2023" />

DOPR showed no significant effects on locomotor activity in rodents at the assessed doses, but showed a trend towards hyperlocomotion at the highest dose.<ref name="CunninghamBockSerrano2023" /> In a subsequent study however, it produced hyperlocomotion at lower doses and hypolocomotion at higher doses.<ref name="LuethiGlatfelterPottie2025" /> The drug has shown pro-motivational effects in rodents at sub-hallucinogenic doses or so-called "microdoses".<ref name="NobackKentonKlein2025" /><ref name="NobackKentonKlein2022" /><ref name="NobackFlesherCuccurazzu2026" /> DOPR's close analogue DOET has also been clinically studied at sub-hallucinogenic doses as a "psychic energizer".<ref name="Baggott2023">{{cite journal | vauthors = Baggott MJ | title=Learning about STP: A Forgotten Psychedelic from the Summer of Love | journal=History of Pharmacy and Pharmaceuticals | volume=65 | issue=1 | date=1 October 2023 | issn=2694-3034 | doi=10.3368/hopp.65.1.93 | doi-access=free | pages=93–116 | url=https://hopp.uwpress.org/content/wphopp/65/1/93.full.pdf | access-date=26 January 2025}}</ref><ref name="Shulgin1978">{{cite book | veditors = Iversen LL, Iversen SD, Snyder SH | vauthors = Shulgin AT | title=Stimulants | chapter=Psychotomimetic Drugs: Structure-Activity Relationships | publisher=Springer US | publication-place=Boston, MA | date=1978 | isbn=978-1-4757-0512-6 | doi=10.1007/978-1-4757-0510-2_6 | pages=243–333 | chapter-url=https://bitnest.netfirms.com/external/10.1007/978-1-4757-0510-2_6 | url=https://books.google.com/books?id=h0_uBwAAQBAJ&pg=PA261 }}</ref><ref name="SnyderFaillaceWeingartner1968">{{cite journal | vauthors = Snyder SH, Faillace LA, Weingartner H | title = DOM (STP), a new hallucinogenic drug, and DOET: effects in normal subjects | journal = Am J Psychiatry | volume = 125 | issue = 3 | pages = 113–120 | date = September 1968 | pmid = 4385937 | doi = 10.1176/ajp.125.3.357 | url = }}</ref><ref name="SnyderFaillace1969">{{cite journal | vauthors = Snyder SH, Faillace LA, Weingartner H | title = A new psychotropic agent. Psychological and physiological effects of 2,5-dimethoxy-4-ethyl amphetamine (DOET) in man | journal = Arch Gen Psychiatry | volume = 21 | issue = 1 | pages = 95–101 | date = July 1969 | pmid = 4389442 | doi = 10.1001/archpsyc.1969.01740190097014 | url = }}</ref><ref name="SnyderWeingartnerFaillace1971">{{cite journal | vauthors = Snyder SH, Weingartner H, Faillace LA | title = DOET (2,5-dimethoxy-4-ethylamphetamine), a new psychotropic drug. Effects of varying doses in man | journal = Arch Gen Psychiatry | volume = 24 | issue = 1 | pages = 50–55 | date = January 1971 | pmid = 4923215 | doi = 10.1001/archpsyc.1971.01750070052006 | url = }}</ref><ref name="SnyderUngerBlatchley1974">{{cite journal | vauthors = Snyder SH, Unger S, Blatchley R, Barfknecht CF | title = Stereospecific actions of DOET (2,5-dimethoxy-4-ethylamphetamine) in man | journal = Arch Gen Psychiatry | volume = 31 | issue = 1 | pages = 103–106 | date = July 1974 | pmid = 4599412 | doi = 10.1001/archpsyc.1974.01760130079013 | url = }}</ref> DOPR produces antidepressant-like effects in rodents.<ref name="NobackFlesherCuccurazzu2026">{{cite journal | vauthors=Noback M, Flesher M, Cuccurazzu B, Halberstadt A, Young J | title=ACNP 64th Annual Meeting: Poster Abstracts P584-P872: The psychedelic DOPR improves depression-related behavior in mice | journal=Neuropsychopharmacology | volume=51 | issue=S1 | date=2026 | issn=0893-133X | pmid=41507446 | pmc=12783840 | doi=10.1038/s41386-025-02281-2 | pages=410–571 | url=https://www.nature.com/articles/s41386-025-02281-2 | access-date=18 January 2026}}</ref>

At higher doses, DOPR produces hypothermia in rodents.<ref name="LuethiGlatfelterPottie2025" />

===Pharmacokinetics=== DOPR crosses the blood–brain barrier in rodents.<ref name="LuethiGlatfelterPottie2025" /> The drug showed the highest brain/plasma ratio among DOM homologues in rodents, whereas 2,5-dimethoxyamphetamine (2,5-DMA) showed the lowest.<ref name="LuethiGlatfelterPottie2025" /> This was involved in potency differences between the drugs.<ref name="LuethiGlatfelterPottie2025" />

==Chemistry== ===Synthesis=== The chemical synthesis of DOPR has been described.<ref name="PiHKAL" />

===Analogues=== Analogues of DOPR include DOM, DOET, DOiP, DOBU, DOAM, DOPF, 2C-P, and 4C-P, among others.<ref name="PiHKAL"/>

==History== DOPR was first described in the literature by Alexander Shulgin in 1970.<ref name="US3547999">{{cite web | title=phenethylamines and their pharmacologically-acceptable salts | website=Google Patents | date=14 July 1969 | url=https://patents.google.com/patent/US3547999 | access-date=27 November 2025}}</ref> Subsequently, it was described in greater detail by Shulgin in his 1991 book ''PiHKAL'' (''Phenethylamines I Have Known and Loved'').<ref name="PiHKAL" />

==Society and culture== ===Legal status=== ====Canada==== DOPR is a controlled substance in Canada under phenethylamine blanket-ban language.<ref name="CDSA">{{cite web | title=Controlled Drugs and Substances Act | website=Department of Justice Canada | url=https://laws-lois.justice.gc.ca/eng/acts/c-38.8/FullText.html | access-date=19 January 2026}}</ref>

====United States==== DOPR is not an explicitly controlled substance in the United States.<ref name="OrangeBook2026">{{citation | title = Orange Book: List of Controlled Substances and Regulated Chemicals (January 2026) | date = January 2026 | publisher = U.S. Department of Justice: Drug Enforcement Administration (DEA): Diversion Control Division | location = United States | url = https://www.deadiversion.usdoj.gov/schedules/orangebook/orangebook.pdf}}</ref> However, it could be considered a controlled substance under the Federal Analogue Act if intended for human consumption.

==References== {{Reflist}}

==External links== * [https://isomerdesign.com/pihkal/explore/71 DOPR - Isomer Design] * [https://web.archive.org/web/20230604135915/https://tripbot.tripsit.me/factsheet/DOPR DOPR - TripSit] * [https://www.bluelight.org/xf/threads/659184 The Small & Handy DOPR Thread - Bluelight] * [https://erowid.org/library/books_online/pihkal/pihkal071.shtml DOPR - PiHKAL - Erowid] * [https://isomerdesign.com/pihkal/read/pk/71 DOPR - PiHKAL - Isomer Design] * [https://tripsitter.com/dopr/ DOPR: Why It’s Wise to Avoid This Shulgin Psychedelic - Tripsitter]

Category:5-HT2A agonists Category:5-HT2B agonists Category:5-HT2C agonists Category:Designer drugs Category:DOx (psychedelics) Category:PiHKAL Category:Pro-motivational agents Category:Psychedelic phenethylamines