2C-T-15, also known as 4-cyclopropylthio-2,5-dimethoxyphenethylamine or as Sesqui, is a psychoactive drug of the phenethylamine and 2C families.
In his book PiHKAL (Phenethylamines I Have Known and Loved), Alexander Shulgin lists 2C-T-15's dose as greater than 30mg orally and its duration as "several hours". The drug produced threshold effects and possible talkativeness at doses of 6 to 30mg orally, but there were no other effects nor clear hallucinogenic effects. Higher doses were not tested.
2C-T-15 is the 2 carbon homologue of Aleph-15, which has not been synthesized. The full chemical name is 2-[4-(2-cyclopropylthio)-2,5-dimethoxyphenyl]ethanamine. The drug has structural properties similar to 2C-T-2 and other drugs in the 2C-T series.
The chemical synthesis of 2C-T-15 has been described.
2C-T-15 was first described in the scientific literature by Alexander Shulgin and colleagues in 1991. Subsequently, it was described in greater detail in his book PiHKAL (Phenethylamines I Have Known and Loved) that same year.
As of October 31, 2016, 2C-T-15 is a controlled substance (Schedule III) in Canada.
2C-T-15 is a class A drug in the UK under the Misuse of Drugs act.
2C-T-15 is not explicitly illegal in the USA, but possession and sales of 2C-T-15 could be prosecuted under the Federal Analog Act because of its structural similarities to 2C-T-7.