A Simple and Efficient Method for the Preparation of Binaltrorphimine and Derivatives and determination of their K opioid antagonist selectivity

The bimorphinans 1 (binaltrorphimine), 3 , and 7 have been prepared by treatment of the parent morphinan-6-ones naltrexone ( 5 ), naloxone ( 4 ), and dihydrocodeinone ( 6 ), respectively, with N-methylhydrazine sulfate in AcOH at room temperature. Compound 3 showed opioid antagonist potency and selectivity for K receptors which were somewhat lower in comparison to 1 .