Thetoxicity of 2C-B-FLY in humans is unknown. Two deaths occurred in October 2009, inDenmark and theUnited States, after ingestion of a substance that was sold as 2C-B-FLY in a small-time RC shop, but in fact consisted ofBromo-DragonFLY contaminated with a small amount of unidentified impurities.[10]
Notes: The smaller the value, the more avidly the drug binds to the site. All proteins are human unless otherwise specified.Refs:[11][12][13][14][15][16][17][18]
2C-B-FLY is 8-bromo-2,3,6,7-benzo-dihydro-difuran-ethylamine. The full name of the chemical is 2-(8-bromo-2,3,6,7-tetrahydrofuro[2,3-f] [1]benzofuran-4-yl)ethanamine. It has been subject of little formal study, but its appearance as adesigner drug has led theDEA to release analytical results for 2C-B-FLY and several related compounds.
In theory, dihydro-difuran analogs of any of the 2Cx / DOx family of drugs could be made, and would be expected to show similar activity to the parent compounds, 2-CB, DOB, DOM, etc. In the same way that 2C-B-FLY is the dihydro-difuran analog of2C-B, the 8-iodo equivalent, "2C-I-FLY," would be the dihydro-difuran analogue of2C-I, and the 8-methyl equivalent, "2C-D-FLY," would be the dihydro-difuran analogue of2C-D.
Other related compounds can also be imagined and produced in which the alpha carbon of the ethylamine sidechain is methylated, giving the amphetamine derivativeDOB-FLY, with this compound being the dihydro-difuran analogue ofDOB, which can be viewed as the fully unsaturated derivative ofBromo-DragonFLY.
When only one methoxy group of a 2Cx drug is cyclized into a dihydro-furan ring, the resulting compound is known as a "hemifly", (and these could be termed 2- or 5- "hemis," depending on where the single dihydro-furan ring is placed). And when an unsaturated furan ring is inserted, the compound is known as a "hemi-dragonfly". The larger, fully saturated, hexahydro-benzo-dipyran ring derivative has been referred to as "2C-B-MOTH." The 8-bromo group can also be replaced by other groups to produce compounds such asTFMFly.
2C-B-FLY and some selected analogues (SAR).
A large number of symmetrical and asymmetrical derivatives can be produced by using different combinations of ring systems. Because the 2- and 5- positions (using the common phenylethylamine numbering scheme), the 2- and 5-positions of the benzene ring, if named as benzo-difurans are not equivalent.[clarification needed] Asymmetrical combinations have two possible positional isomers, with different pharmacological activities, at the various 5-HT2 subtypes. These compounds were casually referred to as the "2C-B-GNAT," and "2C-B-FLEA" compounds, which contain 5 or 6 membered rings at the 2- vs. 5-positions, respectively. Isomeric "Ψ"-derivatives with the oxygens positioned at the 2,6- positions, andmescaline analogues with the oxygens at 3,5- have also been made, but both are less potent than the corresponding 2,5- isomers.[21][22] The symmetrical aromatic benzodifuran derivatives tend to have the highestbinding affinity at 5-HT2A, but the saturated benzodifuran derivatives have higherefficacy, while the saturated benzodipyran derivatives are more selective for 5-HT2C. A large number of possible combinations have been synthesised and tested for activity, but these represent only a fraction of the many variations that could be produced.[23][24][25][26][27][28][29][30][31][32][33]
2C-B-FLY is unscheduled and uncontrolled in the United States. However, it may fall under the scope of theFederal Analog Act if it is intended for human consumption given its similarity to2C-B.
^abShulgin A, Manning T, Daley P (2011).The Shulgin Index, Volume One: Psychedelic Phenethylamines and Related Compounds. Vol. 1. Berkeley: Transform Press.ISBN978-0-9630096-3-0.2C-B-FLY [733720-95-1] (2-5) [...] (2) Assayed in a drug discrimination paradigm with LSD-trained rats, and for interactions with various serotonin receptors (Monte et al., 1996). (3) Orally active in humans at 2.5-10 mg (Shulgin, 2003). (4) Synthesis (Monte et al., 1996). (5) Mass spectra of 2C-B-FLY, B-FLY and B-DFLY (Reed and Kiddon, 2007).
^"Profile for Aaron Monte".UW-La Crosse. 2013-04-10.Dr. Monte has designed and synthesized several potent and selective drug molecules used to map the structural features of serotonin 5-HT2 receptor proteins, which mediate states of consciousness in the human central nervous system (CNS)
^abHufford S (2007)."An Interview with Ann Shulgin on Psychedelics and Self-Discovery"(PDF).MAPS Newsletter.17 (2).Multidisciplinary Association for Psychedelic Studies:23–24.In one recent case, I said often, too often, that something called 2CB Fly was absolutely great for me. To me, it's the loveliest thing, especially for eroticism. But I found out that it's not interesting to anybody else. I realized that having said that, I was putting things in motion. The Internet was full of 2CB Fly, and people were asking about it and I thought "uh-oh." It turned out that it's a disappointment to most other people. So if I say what my favorite psychedelics are, it's almost meaningless for other people, because they have to find their allies very carefully.
^abcCooke J (1 July 2021)."2C-B-FLY: Is It The Best Psychedelic For Arousal & Sexual Intimacy?".Tripsitter. Retrieved26 March 2025.The overall sentiment for [2C-B-FLY] is that it's one of the most enjoyable of the research psychedelics. Ann Shulgin — wife of Alexander Shulgin and co-author of the books TiHKAL and PiHKAL — once stated that 2C-B-FLY was one of her favorite psychedelics.
^Pottie E, Cannaert A, Stove CP (October 2020). "In vitro structure-activity relationship determination of 30 psychedelic new psychoactive substances by means of β-arrestin 2 recruitment to the serotonin 2A receptor".Archives of Toxicology.94 (10):3449–3460.Bibcode:2020ArTox..94.3449P.doi:10.1007/s00204-020-02836-w.hdl:1854/LU-8687071.PMID32627074.
^Wagmann L, Brandt SD, Stratford A, Maurer HH, Meyer MR (February 2019). "Interactions of phenethylamine-derived psychoactive substances of the 2C-series with human monoamine oxidases".Drug Testing and Analysis.11 (2):318–324.doi:10.1002/dta.2494.PMID30188017.
^Luethi D, Liechti ME (April 2020)."Designer drugs: mechanism of action and adverse effects".Archives of Toxicology.94 (4):1085–1133.Bibcode:2020ArTox..94.1085L.doi:10.1007/s00204-020-02693-7.PMC7225206.PMID32249347.The incorporation of 2'- and 5'-methoxy groups into rigid rings resulted in tetrahydrobenzodifuran and benzodifuran analogs that have been sold as designer drugs. These tetrahydrobenzodifuran and benzodifuran designer drugs are referred to asFLY anddragonFLY analogs, respectively, because of the shape of their chemical structure (Halberstadt et al. 2019; Trachsel et al. 2013)
^Monte AP, Waldman SR, Marona-Lewicka D, Wainscott DB, Nelson DL, Sanders-Bush E, et al. (September 1997). "Dihydrobenzofuran analogues of hallucinogens. 4. Mescaline derivatives".Journal of Medicinal Chemistry.40 (19):2997–3008.CiteSeerX10.1.1.690.9370.doi:10.1021/jm970219x.PMID9301661.
^Chambers JJ, Kurrasch-Orbaugh DM, Nichols DE (August 2002). "Translocation of the 5-alkoxy substituent of 2,5-dialkoxyarylalkylamines to the 6-position: effects on 5-HT(2A/2C) receptor affinity".Bioorganic & Medicinal Chemistry Letters.12 (15):1997–1999.CiteSeerX10.1.1.688.9483.doi:10.1016/S0960-894X(02)00306-2.PMID12113827.
^Nichols DE, Snyder SE, Oberlender R, Johnson MP, Huang XM (January 1991). "2,3-Dihydrobenzofuran analogues of hallucinogenic phenethylamines".Journal of Medicinal Chemistry.34 (1):276–281.doi:10.1021/jm00105a043.PMID1992127.
^Monte AP, Marona-Lewicka D, Parker MA, Wainscott DB, Nelson DL, Nichols DE (July 1996). "Dihydrobenzofuran analogues of hallucinogens. 3. Models of 4-substituted (2,5-dimethoxyphenyl)alkylamine derivatives with rigidified methoxy groups".Journal of Medicinal Chemistry.39 (15):2953–2961.doi:10.1021/jm960199j.PMID8709129.
^Chambers JJ, Kurrasch-Orbaugh DM, Parker MA, Nichols DE (March 2001). "Enantiospecific synthesis and pharmacological evaluation of a series of super-potent, conformationally restricted 5-HT(2A/2C) receptor agonists".Journal of Medicinal Chemistry.44 (6):1003–1010.CiteSeerX10.1.1.691.362.doi:10.1021/jm000491y.PMID11300881.
^Chambers JJ, Parrish JC, Jensen NH, Kurrasch-Orbaugh DM, Marona-Lewicka D, Nichols DE (July 2003). "Synthesis and pharmacological characterization of a series of geometrically constrained 5-HT(2A/2C) receptor ligands".Journal of Medicinal Chemistry.46 (16):3526–3535.CiteSeerX10.1.1.688.3544.doi:10.1021/jm030064v.PMID12877591.
^Monte AP, Marona-Lewicka D, Parker MA, Wainscott DB, Nelson DL, Nichols DE (July 1996). "Dihydrobenzofuran analogues of hallucinogens. 3. Models of 4-substituted (2,5-dimethoxyphenyl)alkylamine derivatives with rigidified methoxy groups".Journal of Medicinal Chemistry.39 (15):2953–2961.doi:10.1021/jm960199j.PMID8709129.
^abKent J (17 June 2022)."Remembering Psychedelic Chemist Alexander Shulgin".Psychedelic Spotlight. Retrieved26 March 2025.Ann and Sasha often experimented with psychedelics together, and shared their findings with their confidential research group. "Different people have different body types, so Sasha thought it was important to see how a drug reacts in all kinds of people." When I ask Ann what Sasha's favorite of his own chemicals is she knows immediately. "It would have to be 2C-B. He was always very proud of that one. He called it the Great Teacher. Although I preferred 2C-B-Fly a bit more." But there are so many to choose from. DiPT, 5-MeO-AMT, 5-MeO-DALT, Methylone, 2C-T-7, and this list goes on. Ann can't say for sure how many trips they shared together, she just smiles and says, "We stopped counting at around two-thousand." This is a mind-boggling number considering the total may actually be closer to four-thousand.
^Connie Littlefield (director, writer), Siobhan Flanagan,Alexander Shulgin (subject),Ann Shulgin (subject), Paul F. Daley (subject),Myron Stolaroff (subject), Jean Stolaroff (subject), Wendy Perry Tucker (subject), Tania Manning (subject), Greg Manning (subject),Keeper Trout (subject), Earth and Fire Erowid, others (2021).Better Living Through Chemistry (Motion picture). Better Living Through Film, Incorporated. Event occurs at ~49:50. Archived fromthe original on 21 September 2021.
Notes: (1) TAAR1 activity of ligands varies significantly between species. Some agents that are TAAR1 ligands in some species are not in other species. This navbox includes all TAAR1 ligands regardless of species. (2) See the individual pages for references, as well as theList of trace amines,TAAR, andTAAR1 pages. See also:Receptor/signaling modulators
