Activation of μ‐opioid receptors by MT‐45 (1‐cyclohexyl‐4‐(1,2‐diphenylethyl)piperazine) and its fluorinated derivatives

Background and Purpose A fluorinated derivative (2F‐MT‐45) of the synthetic μ‐opioid receptor agonist MT‐45 (1‐cyclohexyl‐4‐(1,2‐diphenylethyl)piperazine) was recently identified in a seized illicit tablet. While MT‐45 is a Class A drug, banned in a number of countries, nothing is known about the pharmacology of 2F‐MT‐45. This study compares the pharmacology of MT‐45, its fluorinated derivatives and two of its metabolites. Experimental Approach...