Last updated
Clinical data
Other names4-Acetoxy-MET; Metacetin; 4-Acetoxy-N-methyl-N-ethyltryptamine
  • [3-[2-[ethyl(methyl)amino]ethyl]-1H-indol-4-yl] acetate
CAS Number
PubChem CID
Chemical and physical data
Formula C15H20N2O2
Molar mass 260.337 g·mol−1
3D model (JSmol)
  • CCN(C)CCc1c[nH]c2c1c(ccc2)OC(=O)C
  • InChI=1S/C15H20N2O2/c1-4-17(3)9-8-12-10-16-13-6-5-7-14(15(12)13)19-11(2)18/h5-7,10,16H,4,8-9H2,1-3H3

4-Acetoxy-MET (4-Acetoxy-N-methyl-N-ethyl tryptamine), also known as metacetin or 4-AcO-MET, is a hallucinogenic tryptamine. It is the acetate ester of 4-HO-MET, and a homologue of 4-AcO-DMT. It is a novel compound with very little history of human use. [1] It is sometimes sold as a research chemical by online retailers.

It is expected that the compound is quickly hydrolyzed into the free phenolic 4-HO-MET by serum esterases, but human studies concerning the metabolic fate of this drug are lacking.[ citation needed ]


4-Acetoxy-MET is unscheduled in the United States. It may be considered an analogue of Psilocin, a Schedule I drug under the Controlled Substances Act. As such, the sale for human consumption or the use for illicit non-medical purposes could be considered a crime under the Federal Analogue Act[ citation needed ]

4-Acetoxy-MET is a controlled substance in Switzerland under Verzeichnis E [2]

4-Acetoxy-MET is a Class A drug in the UK because it is an ester of the drug 4-HO-MET, which is a Class A drug under the tryptamine catch-all clause [3]

Related Research Articles

Psilocin Psychedelic substance

Psilocin is a substituted tryptamine alkaloid and a serotonergic psychedelic substance. It is present in most psychedelic mushrooms together with its phosphorylated counterpart psilocybin. Psilocin is a Schedule I drug under the Convention on Psychotropic Substances. The mind-altering effects of psilocin are highly variable and subjective and resemble those of LSD and DMT.

A designer drug is a structural or functional analog of a controlled substance that has been designed to mimic the pharmacological effects of the original drug, while avoiding classification as illegal and/or detection in standard drug tests. Designer drugs include psychoactive substances that have been designated by the European Union as new psychoactive substances (NPS) as well as analogs of performance-enhancing drugs such as designer steroids. Some of these were originally synthesized by academic or industrial researchers in an effort to discover more potent derivatives with fewer side effects, and shorter duration and were later co-opted for recreational use. Other designer drugs were prepared for the first time in clandestine laboratories. Because the efficacy and safety of these substances have not been thoroughly evaluated in animal and human trials, the use of some of these drugs may result in unexpected side effects.

Diethyltryptamine Chemical compound

DET, also known under its chemical name N,N-diethyltryptamine and as T-9, is a psychedelic drug closely related to DMT and 4-HO-DET. However, despite its structural similarity to DMT, its activity is induced by an oral dose of around 50–100 mg, without the aid of MAO inhibitors, and the effects last for about 2–4 hours.


4-HO-DET, also known as 4-hydroxy-diethyl-tryptamine, CZ-74, is a hallucinogenic drug and psychedelic compound of moderate duration. 4-HO-DET is a substituted tryptamine, structurally related to psilocin, ethocybin, and 4-HO-DIPT.


4-Acetoxy-DET (4-Acetoxy-N,N-diethyltryptamine), also known as ethacetin, ethylacybin or 4-AcO-DET, is a psychedelic tryptamine. It was first synthesized in 1958 by Albert Hofmann in the Sandoz lab.

5-MeO-MiPT Chemical compound

5-MeO-MiPT is a psychedelic and hallucinogenic drug, used by some as an entheogen. It has structural and pharmacodynamic properties similar to the drugs 5-MeO-DiPT, DiPT, and MiPT. It is commonly used as a "substitute" for 5-MeO-DiPT because of the very similar structure and effects.

4-Acetoxy-DiPT Chemical compound

4-Acetoxy-DiPT is a synthetic psychedelic tryptamine. It is relatively uncommon and has only a short history of human use.

ALD-52 Chemical compound

ALD-52, also known as 1-acetyl-LSD, is a chemical analogue of lysergic acid diethylamide (LSD). It was originally discovered by Albert Hofmann in 1957 but was not widely studied until the rise in popularity of psychedelics in the 1960s.

4-HO-MiPT Chemical compound

4-HO-MiPT is a synthetic substituted aromatic compound and a lesser-known psychedelic tryptamine. It is thought to be a serotonergic psychedelic, similar to magic mushrooms, LSD and mescaline. Its molecular structure and pharmacological effects somewhat resemble those of the tryptamine psilocin, which is the primary psychoactive chemical in magic mushrooms.

<i>O</i>-Acetylpsilocin Chemical compound

O-Acetylpsilocin is a semi-synthetic psychoactive drug that has been suggested by David Nichols to be a potentially useful alternative to psilocybin for pharmacological studies, as they are both believed to be prodrugs of psilocin. However, some users report that O-acetylpsilocin's subjective effects differ from those of psilocybin and psilocin. Some users prefer it over natural psilocybin mushrooms due to feeling less of adverse side effects such as nausea, and heavy body load, which the natural mushroom sometimes tend to produce. It is the acetylated form of the psilocybin mushroom alkaloid psilocin and is a lower homolog of 4-AcO-MET, 4-AcO-DET, 4-AcO-MiPT and 4-AcO-DiPT.


Ethocybin is a homologue of the mushroom alkaloid psilocybin, and a semi-synthetic psychedelic alkaloid of the tryptamine family. Effects of ethocybin are comparable to those of a shorter LSD or psilocybin trip, although intensity and duration vary depending on dosage, individual physiology, and set and setting.

4-HO-MET Chemical compound

4-HO-MET, is a lesser-known psychedelic drug. It is a structural− and functional analog of psilocin as well as the 4-hydroxyl analog of methylethyltryptamine (MET). 4-HO-MET was first synthesized by Alexander Shulgin. In his book TiHKAL, the dosage is listed as 10-20 mg. 4-HO-MET produces psilocin-like distortion of color, sound, and form. Very little data exists about the pharmacological properties, metabolism, and toxicity of 4-HO-MET. There have been no reports of deaths from 4-HO-MET, even though people have reported taking doses up to 150 mg, more than an order of magnitude above the effective dose.

4-HO-MPT Chemical compound

4-Hydroxy-N-methyl-N-propyltryptamine, commonly known as 4-HO-MPT or meprocin, is a psychedelic drug in the tryptamine class of chemical compounds and is a higher homologue of the naturally occurring substituted tryptamine psilocin as well as being the 4-hydroxyl analog of MPT.

5-IT Chemical compound

5-(2-Aminopropyl)indole is an indole and phenethylamine derivative with empathogenic effects. Its preparation was first reported by Albert Hofmann in 1962. It is a designer drug that has been openly sold as a recreational drug by online vendors since 2011.

4-MeO-PCP Chemical compound

4-Methoxyphencyclidine is a dissociative anesthetic drug that has been sold online as a research chemical. The synthesis of 4-MeO-PCP was first reported in 1965 by the Parke-Davis medicinal chemist Victor Maddox. A 1999 review published by a chemist using the pseudonym John Q. Beagle suggested the potency of 4-MeO-PCP in man was reduced relative to PCP, two years later Beagle published a detailed description of the synthesis and qualitative effects of 4-MeO-PCP, which he said possessed 70% the potency of PCP. 4-MeO-PCP was the first arylcyclohexylamine research chemical to be sold online, it was introduced in late 2008 by a company trading under the name CBAY and was followed by several related compounds such as 3-MeO-PCP and methoxetamine. 4-MeO-PCP has lower affinity for the NMDA receptor than PCP, but higher affinity than ketamine, it is orally active in a dosage range similar to ketamine, with some users requiring doses in excess of 100 mg for desired effects. Users have reported substantial differences in active dose, these discrepancies can be partially explained by the presence of unreacted PCC and other impurities in samples sold on the grey market. 4-MeO-PCP has Ki values of 404 nM for the NMDA receptor, 713 nM for the norepinephrine transporter, 844 nM for the serotonin transporter, 296 nM for the σ1 receptor and 143 nM for the σ2 receptor.

Ethylpropyltryptamine Chemical compound

Ethylpropyltryptamine is a rarely encountered psychedelic substance from the tryptamine class, which makes it structurally related to DMT, MET, DET, and DPT.

4-HO-EPT Chemical compound

4-HO-EPT (4-hydroxy-N-ethyl-N-propyltryptamine) is a rarely encountered chemical compound of the tryptamine class, which makes it structurally related to psilocin (4-HO-DMT).

4-AcO-DPT Chemical compound

4-Acetyloxy-N,N-dipropyltryptamine is a tryptamine derivative. 4-AcO-DPT has been sold as a designer drug. It is an ester of 4-HO-DPT, a psychedelic tryptamine first synthesized by Alexander Shulgin. Anecdotal reports indicate that 4-AcO-DPT exerts psychoactive effects in humans, however, the pharmacology of 4-AcO-DPT has not been examined.


5-MeO-MET (5-Methoxy-N-methyl-N-ethyltryptamine) is a relatively rare designer drug from the substituted tryptamine family, related to compounds such as N-methyl-N-ethyltryptamine and 5-MeO-DMT. It was first synthesised in the 1960s and was studied to a limited extent, but was first identified on the illicit market in June 2012 in Sweden. It was made illegal in Norway in 2013, and is controlled under analogue provisions in numerous other jurisdictions.


  1. "New psychoactive substances reported to the EMCDDA and Europol for the first time in 2009 under the terms of Council Decision 2005/387/JHA" (PDF). www.emcdda.europa.eu. Retrieved 6 May 2022.
  2. "Fedlex". www.fedlex.admin.ch. Retrieved 2021-08-15.
  3. "Misuse of Drugs Act 1971". 2021-08-15. Archived from the original on 2012-11-11.