4-Methylaminorex

4-Methylaminorex
Skeletal formula
Ball-and-stick model of 4-methylaminorex
Clinical data
Routes of
administration		Oral, Vaporized, Insufflated, Injected
Legal status
Legal status
Pharmacokinetic data
Bioavailability62% oral; 79% nasal; 91 - 93.5% smoked; 100% IV
MetabolismHepatic
Elimination half-life10-19 hours
ExcretionRenal
Identifiers
  • 4-Methyl-5-phenyl-4,5-dihydro-1,3-oxazol-2-amine
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
CompTox Dashboard (EPA)
Chemical and physical data
FormulaC10H12N2O
Molar mass176.219 g·mol−1
3D model (JSmol)
ChiralityRacemic mixture
  • CC1C(C2=CC=CC=C2)OC(N)=N1
  • InChI=1S/C10H12N2O/c1-7-9(13-10(11)12-7)8-5-3-2-4-6-8/h2-7,9H,1H3,(H2,11,12) checkY
  • Key:LJQBMYDFWFGESC-UHFFFAOYSA-N checkY
 ☒NcheckY (what is this?)  (verify)

4-Methylaminorex (4-MAR, 4-MAX) is a stimulant drug of the 2-amino-5-aryloxazoline class that was first synthesized in 1960 by McNeil Laboratories.[2] It is also known by its street name "U4Euh" ("Euphoria"). It is banned in many countries as a stimulant.

4-Methylaminorex has effects comparable to methamphetamine but with a longer duration.

The results of animal experiments conducted with this drug suggest that it has an abuse liability similar to cocaine and amphetamine. One study found that, "stimulus properties of racemic cis, racemic trans, and all four individual optical isomers of 4-methylaminorex were examined in rats trained to discriminate 1 mg/kg of S(+)amphetamine sulfate from saline. The S(+)amphetamine stimulus generalized to all of the agents investigated".[3] A second study in which rats trained to discriminate either 0.75 mg/kg S(+)-amphetamine or 1.5 mg/kg fenfluramine from saline generalized to aminorex as amphetamine stimulus but not to fenfluramine.[4] Rats trained to discriminate 8 mg/kg cocaine from saline generalized 4-methylaminorex to cocaine-stimulus.[5] The reinforcing effects of cis-4-methylaminorex were determined in two models of intravenous drug self-administration in primates. Vehicle or 4-methylaminorex doses were substituted for cocaine. One of the two different doses of 4-methylaminorex maintained self-administration behavior above vehicle control levels.[6]

  1. ^ Anvisa (2023-07-24). "RDC Nº 804 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial" [Collegiate Board Resolution No. 804 - Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control] (in Brazilian Portuguese). Diário Oficial da União (published 2023-07-25). Archived from the original on 2023-08-27. Retrieved 2023-08-27.
  2. ^ US 3278382, "2-amino-5-aryloxazoline compositions and methods of using same" 
  3. ^ Glennon RA, Misenheimer B (March 1990). "Stimulus properties of a new designer drug: 4-methylaminorex ("U4Euh")". Pharmacology, Biochemistry, and Behavior. 35 (3): 517–21. doi:10.1016/0091-3057(90)90282-M. PMID 1971111. S2CID 10464868.
  4. ^ Young R (May 1992). "Aminorex produces stimulus effects similar to amphetamine and unlike those of fenfluramine". Pharmacology, Biochemistry, and Behavior. 42 (1): 175–8. doi:10.1016/0091-3057(92)90462-O. PMID 1356272. S2CID 31002190.
  5. ^ Young R, Glennon RA (May 1993). "Cocaine-stimulus generalization to two new designer drugs: methcathinone and 4-methylaminorex". Pharmacology, Biochemistry, and Behavior. 45 (1): 229–31. doi:10.1016/0091-3057(93)90110-F. PMID 8516363. S2CID 7648152.
  6. ^ Mansbach RS, Sannerud CA, Griffiths RR, Balster RL, Harris LS (October 1990). "Intravenous self-administration of 4-methylaminorex in primates". Drug and Alcohol Dependence. 26 (2): 137–44. doi:10.1016/0376-8716(90)90120-4. PMID 2242714.