2C-B-FLY

2C-B-FLY is a psychedelic phenethylamine and the dihydrodifuran analog of 2C-B, in which the two methoxy groups of the parent compound are incorporated into a pair of dihydrofuran rings that "butterfly" around the phenethylamine core — giving the compound its distinctive "FLY" suffix and its common name. It was first synthesized by Aaron Monte and reported in the scientific literature in 1999, predating the broader research chemical boom that would bring phenethylamines to wider public attention.

The compound produces a profound, long-duration psychedelic experience at doses in the 5–15 mg range — making it significantly more potent by weight than 2C-B, which requires 15–30 mg for comparable effects. The experience is characterized by visual phenomena and sensory enhancement similar to other 2C compounds but frequently described as smoother and more aesthetic, with a particular richness of color and geometric patterning. Duration is notably extended compared to 2C-B: 5–8 hours is typical, with lingering perceptual effects potentially extending the total timeline.

A critical safety concern distinguishes 2C-B-FLY from most psychedelics: the dose-response curve is steep and individual sensitivity varies dramatically. Doses that are mildly active for one person can be overwhelming or even medically dangerous for another. Reports of unexpectedly intense experiences at apparently moderate doses have circulated in the harm reduction community, and the compound's cardiovascular effects at high doses appear to be more pronounced than 2C-B. The microdosing community has shown interest in 2C-B-FLY, with reports of subtle perceptual enhancement and mood improvement at sub-threshold doses.