Delta agonist hydroxy bioisosteres: The discovery of 3-((1-benzylpiperidin-4-yl){4-[(diethylamino)carbonyl]phenyl}amino)benzamide with improved delta agonist activity and in vitro metabolic stability

We have investigated phenol replacements in a series of diaryl amino piperidine delta opioid agonists. From this study we have demonstrated that the hydroxy functional group can be replaced with a primary amide group, giving enhanced activity at the delta receptor, increased selectivity versus mu and kappa as well as improved in vitro metabolic stability.

Graphical abstractThe primary amide was found to be a suitable replacement for the hydroxy group in a series of delta agonists. Compound 14 displayed potent agonism and improved metabolic stability.Figure optionsDownload full-size imageDownload as PowerPoint slide