U-47109

Two benzamide amines I  [67579-13-9] and II  [82657-23-6] and two benzeneacetamide amines III  [67197-92-6] and IV  [67198-13-4] were synthesized and tested for opioid receptor-mediated pharmacol. activity.I and II had morphine-like behavioral and analgesic activity.In contrast, IV and, to a lesser extent, III had opioid receptor-mediated (naloxone-blocked) analgesic activity, but no behavioral activity.Apparently, the observed activity of IV is due to its non-μ (κ) opioid receptor agonist activity.Structure-activity relations are discussed.