Design, synthesis and biological evaluation of novel tetrahydroisoquinoline quaternary derivatives as peripheral κ-opioid receptor agonists.

A novel series of tetrahydroisoquinoline quaternary derivatives 4 were synthesized as peripheral κ-opioid receptor agonists. All the target compounds were evaluated in κ-opioid receptor binding assays, and compounds 4l , 4m , and 4n exhibited high affinity for κ-opioid receptor. Furthermore, compound 4l (κ K i = 0.94 nM) produced potent antinociceptive activity in the mouse acetic acid-induced writhing assay, with lower sedative side effects than the parent compound MB-1c. [ABSTRACT FROM AUTHOR]