MTFEM

Not to be confused with MTF (male-to-female).

MTFEM, also known as 4-(2,2,2-trifluoroethoxy)-2,5-dimethoxyamphetamine, is a serotonin receptor modulator of the phenethylamine, amphetamine, and DOx families.^[1] It is a derivative of the DOx psychedelics TMA-2 and MEM in which the 4-position substituent has been extended.^[1] The drug is also the α-methyl or amphetamine analogue of 2C-O-22.^[1]

MTFEM

Clinical data
Other names	4-(2,2,2-Trifluoroethoxy)-2,5-dimethoxyamphetamine; 2,5-Dimethoxy-4-(2,2,2-trifluoroethoxy)amphetamine
Drug class	Serotonin 5-HT2 receptor modulator
ATC code	None
Identifiers
IUPAC name 1-[2,5-dimethoxy-4-(2,2,2-trifluoroethoxy)phenyl]propan-2-amine
PubChem CID	172547198
Chemical and physical data
Formula	C13H18F3NO3
Molar mass	293.286 g·mol−1
3D model (JSmol)	Interactive image
SMILES COc1cc(CC(N)C)c(cc1OCC(F)(F)F)OC
InChI InChI=InChI=1S/C13H18F3NO3/c1-8(17)4-9-5-11(19-3)12(6-10(9)18-2)20-7-13(14,15)16/h5-6,8H,4,7,17H2,1-3H3 Key:LFPUPGGEYLURDG-UHFFFAOYSA-N

Use and effects

In humans, MTFEM produced stimulant effects at a dose of 2.5 mg and had a duration of 12 hours.^[2] Its full effects in humans were not determined and it was estimated that its human dose range would be 10 mg or more.^[2] Along with TMA-2 and MEM, it is one of the few compounds in its series tested and known to be active in humans.^[2]

Pharmacology

MTFEM acts as a potent modulator of the serotonin 5-HT₂ receptors.^[1] Its affinities (K_i) were 460 nM for the serotonin 5-HT_2A receptor and 2,400 nM for the serotonin 5-HT_2C receptor, whereas its activational potencies (EC₅₀Tooltip half-maximal effective concentration (E_maxTooltip maximal efficacy)) were 19 nM (80%) at the serotonin 5-HT_2A receptor and 200 nM (4.8%) at the serotonin 5-HT_2B receptor.^[1] Hence, MTFEM is a near-full agonist of the serotonin 5-HT_2A receptor but a near-silent antagonist of the serotonin 5-HT_2B receptor.^[1] Besides the serotonin 5-HT₂ receptors, the drug showed little to no activity at various other assessed targets, such as the monoamine transporters.^[1] It does not appear to have been tested for psychedelic-like activity in animals.^[1]

History

MTFEM was first described in the scientific literature by Daniel Trachsel in 2012.^[3][2] Its psychoactive effects in humans were reported by Trachsel and colleagues in 2013.^[2] Subsequently, it was characterized in more detail by a group including Trachsel and Matthias Liechti in 2019.^[1] The compound's name is said to derive from its benzene ring substituents, "methoxy trifluoroethoxy methoxy".^[1]

See also

• DOx (psychedelics)
• MEM § Derivatives