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] benzofuran-4-yl)ethanamine. It has been subject to little formal study, but its appearance as a designer drug has led the DEA to release analytical results for 2C-B-FLY and several related compounds.
In theory, dihydrodifuran analogues of any of the 2Cx / DOx family of drugs could be made, and would be expected to show similar activity to the parent compound. So in the same way that 2C-B-FLY is the dihydrodifuran analogue of 2C-B, the 8-iodo equivalent 2C-I-FLY would be the dihydrodifuran analogue of 2C-I, and the 8-methyl equivalent 2C-D-FLY would be the dihydrodifuran analogue of 2C-D.
Other related compounds can also be produced, where the alpha carbon of the ethylamine chain is methylated, the amphetamine derivative DOB-FLY can be made, this compound being the dihydrodifuran analogue of DOB, or conversely can be viewed as the saturated derivative of Bromo-DragonFLY.
Where only one methoxy group of a 2Cx drug is cyclised into a dihydrofuran ring, the resulting compound is known as a "hemifly", and when an unsaturated furan ring is used, the compound is known as a "hemi-dragonfly". The larger saturated hexahydrobenzodipyran ring derivatives have been referred to as "butterfly" compounds. The 8-bromo group can also be replaced by other groups to give compounds such as TFMFly.
A large number of symmetrical and unsymmetrical derivatives can be produced by using different combinations of ring systems. Because the 2- and 5- positions (using phenethylamine numbering scheme, 1,5-positions if numbered as benzodifuran) are not equivalent, all unsymmetrical combinations also have two possible positional isomers, with different potencies at the various 5-HT2 subtypes. Isomeric "Ψ"-derivatives with the oxygens positioned at the 2,6- positions, and mescaline analogues with the oxygens at 3,5- have also been made, but both are less potent than the corresponding 2,5- isomers. The symmetrical aromatic benzodifuran derivatives tend to have the highest binding affinity at 5-HT2A, but the saturated benzodifuran derivatives have higher efficacy, 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.
The toxicity of 2C-B-FLY in humans is unknown. Two deaths occurred in October 2009, in Denmark and the United States, after ingestion of a substance that was sold as 2C-B-FLY a small-time RC shop, but in fact consisted of Bromo-DragonFLY contaminated with a small amount of unidentified impurities.
As of October 31, 2016; 2C-B-FLY is a controlled substance (Schedule III) in Canada. [gazette.gc.ca]
2C-B-FLY is unscheduled and uncontrolled in the United States. However, it may fall under the scope of the Federal Analog Act if it is intended for human consumption given its similarity to 2C-B.
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