Psychedelic Research Chemicals or RC Chems are new synthetic substances which are structurally similar to the original drug, while being functional analogs. Data on their effects limited due as they’re fairly new and do not have a lot of human consumption history.

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This is an Experimental Substance with little data. This is most likely because the substance is is not very old. Information is limite and incomplete.

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2C-T-21 Also known as:

  • 2-{4-[(2-Fluorethyl)sulfanyl]-2,5-dimethoxyphenyl}ethanamin[German][ACD/IUPAC Name]
  • 2-{4-[(2-Fluoroethyl)sulfanyl]-2,5-dimethoxyphenyl}ethanamine[ACD/IUPAC Name]
  • 2-{4-[(2-Fluoroéthyl)sulfanyl]-2,5-diméthoxyphényl}éthanamine[French][ACD/IUPAC Name]
  • 2C-T-21
  • Benzeneethanamine, 4-[(2-fluoroethyl)thio]-2,5-dimethoxy-[ACD/Index Name]
  • 2-[4-(2-Fluoro-ethylsulfanyl)-2,5-dimethoxy-phenyl]-ethylamine

A rare psychedelic phenethylamine.


It is a member of the 2C-x family of psychedelic phenethylamines, all of which were derived from the systematic modification of the mescaline molecule. 2C-T-21 was first synthesized by Alexander Shulgin and documented in his book PiHKAL ("Phenethylamines I Have Known and Loved"). The dosage range is listed as 8–12 mg.

It is described in various reports as being generally relaxed and clear-headed with mild visual effects. In his book “Thanatos To Eros, 35 Years of Psychedelic Exploration”, Myron Stolaroff describes it as “not psychedelic, but a wonderful energizer”, along with displaying a notable lack of appetite suppression typically observed with members of its class. In March 2004, a 22-year-old American male died after ingesting an unknown amount of 2C-T-21.

This death became part of a two-year DEA investigation called “Operation Web Tryp” which ended with the arrests of 10 persons involved in the online distribution of research chemicals. 2C-T-21 remains unscheduled in the United States. Very little data exists about the pharmacological properties, metabolism, and toxicity of 2C-T-21, and it has little history of human usage.

Today, it is used for the purposes of recreation and experimental psychotherapy. It has no history of being sold on the streets and is very sporadically sold online as a grey area research chemical. It is strongly advised to use harm reduction practices if using this substance.


2C-T-21 contain methoxy functional groups CH3O- attached to carbons R2 and R5 of the benzene ring as well as an ethylfluoro thioether group attached to carbon R4 of the phenyl ring. 2C-T-21 belongs to the 2C family of phenethylamines, all of which contain methoxy groups on the 2 and 5 positions of the benzene ring.

Std. InChiInChI=1S/C12H18FNO2S/c1-15-10-8-12(17-6-4-13)11(16-2)7-9(10)3-5-14/h7-8H,3-6,14H2,1-2H3
Avg. Mass259.3402 Da
Molecular Weight259.3402
Monoisotopic Mass259.104218 Da
Nominal Mass259
ChemSpider ID21106231

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Dose Chart


Duration Chart

2C-T-21 Duration Data
Onset15-40 minutes
Duration6-12 hours
After-effects2-12 hours

Legal Status

  • Austria: 2C-T-21 is illegal to possess, produce and sell under the NPSG (Neue-Psychoaktive-Substanzen-Gesetz Österreich).
  • Canada: As of October 31st, 2016; 2C-T-21 is a controlled substance (Schedule III) in Canada.
  • Germany: 2C-T-21 is controlled under the NpSG (New Psychoactive Substances Act) as of November 26, 2016. Production and import with the aim to place it on the market, administration to another person and trading is punishable. Possession is illegal but not penalized.
  • United Kingdom: 2C-T-21 is a Class A drug in the United Kingdom as a result of the phenethylamine catch-all clause.
  • United States: 2C-T-21 is technically not scheduled in the United States, but could be considered an analogue of 2C-T or 2C-T-7 and may therefore be considered a Schedule I drug under the Federal Analogue Act.
  • Sources


    2. | Thanatos to Eros
    4. "News from DEA, News Releases, 07/22/04".
    5. Sulfur-Substituted α-Alkyl Phenethylamines as Selective and Reversible MAO-A Inhibitors:  Biological Activities, CoMFA Analysis, and Active Site Modeling |
    7. "Gesetz zur Bekämpfung der Verbreitung neuer psychoaktiver Stoffe" (PDF) (in German). Bundesanzeiger Verlag. Retrieved December 10, 2019.
    8. "Anlage NpSG" (in German). Bundesministerium der Justiz und für Verbraucherschutz. Retrieved December 10, 2019.
    9. "§ 4 NpSG" (in German). Bundesministerium der Justiz und für Verbraucherschutz. Retrieved December 10, 2019.
    10. United Kingdom. (1977). Misuse of Drugs Act 1971 (S.I. 1977/1243). London: The Stationery Office Limited. Retrieved July 5, 2017, from

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    1. PsychonautWiki is a community-driven online encyclopedia that aims to document the field of psychonautics in a comprehensive, scientifically-grounded manner.
    2. Erowid is a non-profit educational & harm-reduction resource with 60 thousand pages of online information about psychoactive drugs
    3. PubChem National Center for Bio Informatics
    4. Chemspider is a free chemical structure database providing fast access to over 34 million structures, properties and associated information.
    5. Wikipedia

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    Data is constantly updated so please check back later to see if there is any more available information on this substance.