Aminorex

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Aminorex
Aminorex structure.svg
Aminorex molecule ball.png
Clinical data
ATC code
  • none
Legal status
Legal status
Identifiers
  • (RS)-5-Phenyl-4,5-dihydro-1,3-oxazol-2-amine
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEMBL
ECHA InfoCard 100.164.420 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C9H10N2O
Molar mass 162.192 g·mol−1
3D model (JSmol)
Chirality Racemic mixture
  • NC1=NCC(C2=CC=CC=C2)O1
  • InChI=1S/C9H10N2O/c10-9-11-6-8(12-9)7-4-2-1-3-5-7/h1-5,8H,6H2,(H2,10,11) Yes check.svgY
  • Key:SYAKTDIEAPMBAL-UHFFFAOYSA-N Yes check.svgY
   (verify)

Aminorex (Menocil, Apiquel, aminoxaphen, aminoxafen, McN-742) is a weight loss (anorectic) stimulant drug. It was withdrawn from the market after it was found to cause pulmonary hypertension. [2] In the U.S., it is an illegal Schedule I drug, meaning it has high abuse potential, no accepted medical use, and a poor safety profile.

Contents

Aminorex, in the 2-amino-5-aryl oxazoline class, was developed by McNeil Laboratories in 1962. [3] It is closely related to 4-methylaminorex. Aminorex has been shown to have locomotor stimulant effects, lying midway between dextroamphetamine and methamphetamine. Aminorex effects have been attributed to the release of catecholamines. [4] It can be produced as a metabolite of the worming medication levamisole, which is sometimes used as a cutting agent of illicitly produced cocaine. [5] [6]

History

It was discovered in 1962 by Edward John Hurlburt, [7] and was quickly found in 1963 to have an anorectic effect in rats. It was introduced as a prescription appetite suppressant in Germany, Switzerland and Austria in 1965, but was withdrawn in 1972 after it was found to cause pulmonary hypertension in approximately 0.2% of patients, and was linked to a number of deaths. [4] [8]

Synthesis

The synthesis was first reported in a structure-activity relationship study of 2-amino-5-aryl-2-oxazolines, where aminorex was found to be approximately 2.5 times more potent than D-amphetamine sulfate in inducing anorexia in rats, and was also reported to have CNS stimulant effects.

Aminorex rxn mech.png

The racemic synthesis involves addition/cyclization reaction of 2-amino-1-phenylethanol with cyanogen bromide. [9] A similar synthesis has been also published. [10] In a search for a cheaper synthetic route, a German team developed an alternative route [11] which, by using chiral styrene oxide, allows an enantiopure product.

See also

Related Research Articles

<span class="mw-page-title-main">Fenfluramine/phentermine</span> Drug combination prescribed for weight loss; later withdrawn from market

The drug combination fenfluramine/phentermine, usually called fen-phen, was an anti-obesity treatment in the early 1990s that utilized two anorectics. Fenfluramine was marketed by American Home Products as Pondimin, but was shown to cause potentially fatal pulmonary hypertension and heart valve problems, which eventually led to its withdrawal in 1997 and legal damages of over $13 billion. Phentermine was not shown to have harmful effects.

An anorectic or anorexic is a drug which reduces appetite, resulting in lower food consumption, leading to weight loss. By contrast, an appetite stimulant is referred to as orexigenic.

<span class="mw-page-title-main">Phenylacetone</span> Chemical compound

Phenylacetone, also known as phenyl-2-propanone, is an organic compound with the chemical formula C6H5CH2COCH3. It is a colorless oil that is soluble in organic solvents. It is a mono-substituted benzene derivative, consisting of an acetone attached to a phenyl group. As such, its systematic IUPAC name is 1-phenyl-2-propanone.

<span class="mw-page-title-main">2-Imidazoline</span> Chemical compound

2-Imidazoline (Preferred IUPAC name: 4,5-dihydro-1H-imidazole) is one of three isomers of the nitrogen-containing heterocycle imidazoline, with the formula C3H6N2. The 2-imidazolines are the most common imidazolines commercially, as the ring exists in some natural products and some pharmaceuticals. They also have been examined in the context of organic synthesis, coordination chemistry, and homogeneous catalysis.

<span class="mw-page-title-main">4-Methylaminorex</span> Group of stereoisomers

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

<span class="mw-page-title-main">Levamisole</span> Chemical compound

Levamisole, sold under the brand name Ergamisol among others, is a medication used to treat parasitic worm infections, specifically ascariasis and hookworm infections. It is taken by mouth.

<span class="mw-page-title-main">Chlorphentermine</span> Weight loss medication

Chlorphentermine is a serotonergic appetite suppressant of the amphetamine family. Developed in 1962, it is the 4-chloro derivative of the better known appetite suppressant phentermine, which is still in current use.

<span class="mw-page-title-main">Mazindol</span> Stimulant drug and appetite suppressant

Mazindol is a stimulant drug which is used as an appetite suppressant. It was developed by Sandoz-Wander in the 1960s.

<span class="mw-page-title-main">Thozalinone</span> Chemical compound

Thozalinone (USAN) is a psychostimulant that has been used as an antidepressant in Europe. It has also been trialed as an anorectic. Thozalinone is described as a "dopaminergic stimulant", and likely acts via inducing the release of dopamine and to a minimal extent norepinephrine; similar to analogue pemoline, it is reportedly devoid of abuse potential unlike other dopaminergic psychostimulants.

<span class="mw-page-title-main">Fluminorex</span> Chemical compound

Fluminorex is a centrally acting sympathomimetic which is related to other drugs such as aminorex and pemoline. It was developed as an appetite suppressant by McNeil Laboratories in the 1950s.

<span class="mw-page-title-main">RTI-126</span> Pharmaceutical drug

RTI-126 is a phenyltropane derivative which acts as a potent monoamine reuptake inhibitor and stimulant drug, and has been sold as a designer drug. It is around 5 times more potent than cocaine at inhibiting monoamine reuptake in vitro, but is relatively unselective. It binds to all three monoamine transporters, although still with some selectivity for the dopamine transporter. RTI-126 has a fast onset of effects and short duration of action, and its pharmacological profile in animals is among the closest to cocaine itself out of all the drugs in the RTI series. Its main application in scientific research has been in studies investigating the influence of pharmacokinetics on the abuse potential of stimulant drugs, with its rapid entry into the brain thought to be a key factor in producing its high propensity for development of dependence in animals.

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<span class="mw-page-title-main">Cyclazodone</span> Chemical compound

Cyclazodone is a centrally acting stimulant drug developed by American Cyanamid Company in the 1960s. The drug is related to other drugs such as pemoline and thozalinone. It displayed a favorable therapeutic index and margin of safety in comparison to Pemoline and other N-lower-alkyl-substituted Pemoline derivatives. The patents concluded that Cyclazodone possessed properties efficacious in reducing fatigue and as a potential anorectic. Structural congeners of Pemoline have been described as "excitants with unique properties distinguishing them from the sympathomimetic amines" whilst displaying less stimulatory activity and toxicity compared to amphetamine.

<span class="mw-page-title-main">6-Br-APB</span> Chemical compound

6-Br-APB is a synthetic compound that acts as a selective D1 agonist, with the (R)-enantiomer being a potent full agonist, while the (S) enantiomer retains its D1 selectivity but is a weak partial agonist. (R)-6-Br-APB and similar D1-selective full agonists like SKF-81,297 and SKF-82,958 produce characteristic anorectic effects, stereotyped behaviour and self-administration in animals, with a similar but not identical profile to that of dopaminergic stimulants such as amphetamine.

<span class="mw-page-title-main">Arylcyclohexylamine</span> Class of chemical compounds

Arylcyclohexylamines, also known as arylcyclohexamines or arylcyclohexanamines, are a chemical class of pharmaceutical, designer, and experimental drugs.

<span class="mw-page-title-main">Oxazoline</span> Chemical compound

Oxazoline is a five-membered heterocyclic organic compound with the formula C3H5NO. It is the parent of a family of compounds called oxazolines, which contain non-hydrogenic substituents on carbon and/or nitrogen. Oxazolines are the unsaturated analogues of oxazolidines, and they are isomeric with isoxazolines, where the N and O are directly bonded. Two isomers of oxazoline are known, depending on the location of the double bond.

<span class="mw-page-title-main">Cloforex</span> Chemical compound

Cloforex (Oberex) is an anorectic of the amphetamine class. It is a prodrug to chlorphentermine. It never became a mass produced drug in part due to the side effects found in mice. Mice who consumed 75 mg of cloforex a day experienced weight loss along with pulmonary hypertension and hair loss.

<span class="mw-page-title-main">Levofenfluramine</span> Non-marketed drug of the amphetamine class

Levofenfluramine (INN), or (−)-3-trifluoromethyl-N-ethylamphetamine, also known as (−)-fenfluramine or (R)-fenfluramine, is a drug of the amphetamine family that, itself (i.e., in enantiopure form), was never marketed. It is the levorotatory enantiomer of fenfluramine, the racemic form of the compound, whereas the dextrorotatory enantiomer is dexfenfluramine. Both fenfluramine and dexfenfluramine are anorectic agents that have been used clinically in the treatment of obesity (and hence, levofenfluramine has been as well since it is a component of fenfluramine). However, they have since been discontinued due to reports of causing cardiovascular conditions such as valvular heart disease and pulmonary hypertension, adverse effects that are likely to be caused by excessive stimulation of 5-HT2B receptors expressed on heart valves.

<span class="mw-page-title-main">6-Formylindolo(3,2-b)carbazole</span> Chemical compound

6-Formylindolo[3,2-b]carbazole (FICZ) is a chemical compound with the molecular formula C19H12N2O. It is a nitrogen heterocycle, having an extremely high affinity (Kd = 7 x 10−11M) for binding to the aryl hydrocarbon receptor (AHR).

References

  1. Anvisa (2023-03-31). "RDC Nº 784 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial" [Collegiate Board Resolution No. 784 - Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control] (in Brazilian Portuguese). Diário Oficial da União (published 2023-04-04). Archived from the original on 2023-08-03. Retrieved 2023-08-16.
  2. Gaine SP, Rubin LJ, Kmetzo JJ, Palevsky HI, Traill TA (November 2000). "Recreational use of aminorex and pulmonary hypertension". Chest. 118 (5): 1496–7. doi:10.1378/chest.118.5.1496. PMID   11083709. Archived from the original on 2013-01-12.
  3. US 3161650,"2-Amino-5-Aryloxazoline Products"
  4. 1 2 Fishman AP. (Jan 1991). "Aminorex to fen/phen - An epidemic foretold". Circulation. 99 (1): 156–161. doi: 10.1161/01.CIR.99.1.156 . ISSN   0009-7322. PMID   9884392.
  5. Ho EN, Leung DK, Leung GN, Wan TS, Wong AS, Wong CH, Soma LR, Rudy JA, Uboh C, Sams R (April 2009). "Aminorex and rexamino as metabolites of levamisole in the horse". Analytica Chimica Acta. 638 (1): 58–68. Bibcode:2009AcAC..638...58H. doi:10.1016/j.aca.2009.02.033. PMID   19298880.
  6. Bertol E, Mari F, Milia MG, Politi L, Furlanetto S, Karch SB (July 2011). "Determination of aminorex in human urine samples by GC-MS after use of levamisole". Journal of Pharmaceutical and Biomedical Analysis. 55 (5): 1186–9. doi:10.1016/j.jpba.2011.03.039. PMID   21531521.
  7. US 3115494,"2-amino-5, 6-dihydro-4ii-1, 3-oxazines and a process for their preparation"
  8. Weigle DS (June 2003). "Pharmacological therapy of obesity: past, present, and future". The Journal of Clinical Endocrinology and Metabolism. 88 (6): 2462–9. doi: 10.1210/jc.2003-030151 . PMID   12788841.
  9. Poos GI, Carson JR, Rosenau JD, Roszowski AP, Kelley NM, McGowin J (May 1963). "2-Amino-5-aryl-2-oxazolines. Potent New Anorectic Agents". Journal of Medicinal Chemistry. 6 (3): 266–272. doi:10.1021/jm00339a011. PMID   14185981.
  10. Ueda S, Terauchi H, Yano A, Ido M, Matsumoto M, Kawasaki M (Jan 2004). "4,5-Disubstituted-1,3-oxazolidin-2-imine derivatives: a new class of orally bioavailable nitric oxide synthase inhibitor". Bioorg. Med. Chem. Lett. 14 (2): 313–316. doi:10.1016/j.bmcl.2003.11.010. PMID   14698148.
  11. DE Patent 2101424 2-amino-5-phenyl-2-oxazoline preparation