2,4,5-Trimethoxyphenethylamine

2C-O
Clinical data
Other names	2,4,5-TMPEA; TMPEA-2; TMPEA; 4-Methoxy-2,5-dimethoxyphenethylamine; 2,5-Dimethoxy-4-methoxyphenethylamine; 2C-O; 2C-OMe; 2C-MeO; 2C-TMA-2; 25O
Routes of; administration	Oral, injection
Drug class	Serotonin receptor agonist; Serotonin 5-HT2 receptor agonist
ATC code	None;
Legal status
Legal status	CA: Schedule III; UK: Class A; US: Schedule I (isomer of mescaline);
Identifiers
	IUPAC name 2-(2,4,5-trimethoxyphenyl)ethan-1-amine;
CAS Number	15394-83-9 ;
PubChem CID	151954;
ChemSpider	133931 ;
UNII	S27QYQ708U;
ChEMBL	ChEMBL354924 ;
CompTox Dashboard (EPA)	DTXSID30165499 ;
Chemical and physical data
Formula	C11H17NO3
Molar mass	211.261 g·mol−1
3D model (JSmol)	Interactive image;
Melting point	187 to 188 °C (369 to 370 °F)
	SMILES O(c1cc(c(OC)cc1OC)CCN)C;
	InChI InChI=1S/C11H17NO3/c1-13-9-7-11(15-3)10(14-2)6-8(9)4-5-12/h6-7H,4-5,12H2,1-3H3 ; Key:GKATTZLSNLYADI-UHFFFAOYSA-N ;
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2C-O, also known as 2,4,5-trimethoxyphenethylamine (2,4,5-TMPEA) or TMPEA-2, is a serotonin receptor modulator of the phenethylamine and 2C families related to the psychedelic drug mescaline. It is a positional isomer of mescaline (3,4,5-trimethoxyphenethylamine) and is the α-desmethyl analogue of 2,4,5-trimethoxyamphetamine (TMA-2). The drug is the parent compound of the 2C-O series of drugs. 2C-O appears to be inactive in terms of psychoactive effects in humans, at least at doses that have been assessed. In any case, it is a low-potency full agonist of the serotonin 5-HT₂ receptors in vitro, including of the serotonin 5-HT_2A receptor. 2C-O was first described by Max Jansen in 1931 and was further described by Alexander Shulgin in his 1991 book PiHKAL (Phenethylamines I Have Known and Loved).