Synthesis and opiate receptor binding properties of 17-methyl-6,7-dehydro-3,14-dihydroxy-4,5α-epoxy-6,7:4′,5′-pyrimidinomorphinans

A class of opioid receptor active derivatives of oxymorphone has been synthesized using a common enaminone intermediate. The derivatives have heterocyclic groups fused to the 6,7-positions of the morphinan system and all were synthesized in high yield. A pyrazolo derivative is an agonist for the μ and δ receptors and an antagonist for the κ receptor.