1) Synthetic opioid 
Ohmefentanyl (β-hydroxy-3-methylfentanyl, OMF, RTI-4614-4) is an extremely potent opioid analgesic drug which selectively binds to the µ-opioid receptor. The Chinese have recorded ohmefentanyl as having a potency that is 6,300 times morphine. Ohmefentanyl is one of the most potent μ -receptor agonists known, comparable to super-potent opioids s...