Derivatives of 17-(2-methylallyl)-substituted noroxymorphone: Variation ofthe delta address and its effects on affinity and selectivity for the delta opioid receptor

In an effort to establish the importance of the N-(2-methylallyl) substitue nt in the noroxymorphone series, several derivatives have been synthesized, retaining that N-substituent and modifying the delta address moiety. A few compounds showed moderate binding affinity and selectivity for the delta r eceptor; none displayed a pharmacological profile as exceptional as N-(2-me thylallyl)noroxymorphindole, A second study showed that 3-O-methylation of all derivatives decreases binding affinity. The present results indicate th at only a combination of the N-(2-methylallyl) group and an indole delta ad dress provided high selectivity for the delta receptor. Published by Elsevi er Science Ltd.