has role antinociceptive agent cyclohexanones antidepressant analgesic nicotinic antagonist drug metabolite primary amino compound NMDA receptor antagonist human xenobiotic metabolite monochlorobenzenes norketamine A member of the class of cyclohexanones that is cyclohexanone in which one of the hydrogens at position 2 is substituted by a 2-chlorophenyl group, while the other is substituted by an amino group. It is the major metabolite of ketamine.