2,3,5,6-Tetramethoxyphenethylamine

2,3,5,6-Tetramethoxyphenethylamine, also known as TeMPEA-3, is a drug of the phenethylamine family related to the psychedelic drug mescaline. It is one of the possible positional isomers of tetramethoxyphenethylamine.
The in-vitro metabolism and effects of TeMPEA-3 on behavior in animals have been studied. Unlike mescaline, TeMPEA-3 was inactive in the conditioned avoidance response test in rats. The effects of TeMPEA-3 in humans have not been reported and are unknown.
The drug was first described in the scientific literature by 1955. TeMPEA-3 was included as an entry in Alexander Shulgin's 2011 book The Shulgin Index, Volume One: Psychedelic Phenethylamines and Related Compounds. It is a controlled substance in Canada under phenethylamine blanket-ban language.