Synthesis and Characterization of in Vitro and in Vivo Profiles of Hydroxybupropion Analogues: Aids to Smoking Cessation

To create potentially superior aids to smoking cessation and/or antidepressants and to elucidate bupropion's possible mechanisms of action(s), 23 analogues based on its active hydroxymetabolite (2S,35)-4a were synthesized and tested for their abilities to inhibit monoamine uptake and nAChR subtype activities in vitro and acute effects of nicotine in vivo. The 3',4'-dichlorophenyl [(+/-)-4n], naphthyl (4r), and 3-chlorophenyl or 3-propyl analogues 4s and 4t, respectively, had higher inhibitory potency and/or absolute selectivity than (2S,3S)-4a for inhibition of DA, NE, or 5HT uptake. The 3'-fluorophenyl, 3'-bromophenyl, and 4-biphenyl analogues 4c, 4d, and 4l, respectively, had higher potency for antagonism of alpha 4 beta 2-nAChR than (2S,3S)-4a. Several analogues also had higher potency than (2S,35)-4a as antagonists of nicotine-mediated antinociception in the tail-flick assay. The results suggest that compounds acting via some combination of DA, NE, or 5HT inhibition and/or antagonism of alpha 4 beta 2-nAChR can potentially be new pharmacotherapeutics for treatment of nicotine dependence.