5-MeO-DiBF is a psychedelic[1] that has been sold online as a designer drug and was first definitively identified in December 2015 by a forensic laboratory in Slovenia.[2] It is thought to act as an agonist for the 5-HT1A and 5-HT2 family of serotonin receptors. It is related in structure to the psychedelic tryptamine derivative 5-MeO-DiPT, but with the indole nitrogen replaced by oxygen, making 5-MeO-DiBF a benzofuran derivative. It is several times less potent as a serotonin agonist than 5-MeO-DiPT and with relatively more activity at 5-HT1A, but still shows strongest effects at the 5-HT2 family of receptors.[3] [4]
5-MeO-DiBF is not controlled under the 1971 Convention on Psychotropic Substances, so thus it has a legal grey area in many countries, but it's possible it could be illegal under so-called analogue acts if sold for human consumption.