Papers of the Week

A new series of thiophenpiperazine amide derivatives as potent dual ligands for the μ-opioid (MOR) and sigma-1 (σR) receptors are reported. Compound 23 exhibited good affinity to σR (K = 44.7 ± 7.05 nM) and high selectivity to σR. Furthermore, Compound 23 exerted MOR agonism and σ1R antagonism and potent analgesic activity in animal moldes (the abdominal constriction test (ED = 3.83 mg/kg) and carrageenan-induced inflammatory hyperalgesia model (ED = 5.23 mg/kg)). We obtained new dual ligands that might serve as starting points for preparing targeted tools. Furthermore, 23 may be a useful chemical probe for understanding more fully analgesic effects associated with MOR agonism and σR antagonism.