has role kappa-opioid receptor antagonist morphinane alkaloid buprenorphine CHEBI:3216 A morphinane alkaloid that is 7,8-dihydromorphine 6-<em>O</em>-methyl ether in which positions 6 and 14 are joined by a -CH<small>₂</small>CH<small>₂</small>- bridge, one of the hydrogens of the <em>N</em>-methyl group is substituted by cyclopropyl, and a hydrogen at position 7 is substituted by a 2-hydroxy-3,3-dimethylbutan-2-yl group. It is highly effective for the treatment of opioid use disorder and is also increasingly being used in the treatment of chronic pain. opioid analgesic mu-opioid receptor agonist delta-opioid receptor antagonist