25I-NBF
25I-NBF is a derivative of the phenethylamine hallucinogen 2C-I, which acts as a highly potent partial agonist for the human 5-HT2A receptor, with bias towards the β-arrestin 2 coupled signalling pathway. It has been studied in its 11C radiolabelled form as a potential ligand for mapping the distribution of 5-HT2A receptors in the brain, using positron [emission tomography].