Oxilorphan
Oxilorphan (INN, USAN) (developmental code name L-BC-2605) is an opioid antagonist of the morphinan family that was never marketed. It acts as a μ-opioid receptor (MOR) antagonist but a κ-opioid receptor (KOR) partial agonist, and has similar effects to naloxone and around the same potency as an MOR antagonist.