N-cyclohexylethyl-N-noroxymorphindole: a μ-Opioid preferring analogue of naltrindole

The position of the indole in the indolomorphinans, which includes the δ opioid antagonist naltrindole, is considered to be responsible for the δ opioid selectivity for this class of ligands. Herein is described the N-cyclohexylethyl substituted N-nor-derivative, which is shown to be μ preferring. Thus, the nature of the N-substituent is equally important to the receptor selectivity for this class of ligands