KOR agonist 1 (Compound 7a) is a selective activator of opioid receptors, exhibiting EC50 values of 3.4 nM for KOR, 701.2 nM for MOR, and 1649 nM for DOR. Its affinity for these receptors is reflected in Ki values of 3.9 nM for KOR, 1053 nM for MOR, and 4196 nM for DOR. In ICR mouse models, it demonstrates antinociceptive effects with an ED50 of 0.3 mg/kg in the hot plate test and 0.2 mg/kg in the abdominal writhing test.