Further optimization of novel pyrrole 3-carboxamides for targeting serotonin 5-HT(2A), 5-HT(2C), and the serotonin transporter as a potential antidepressant

In the continuing search for novel compounds targeting serotonin 5-HT(2A), 5-HT(2C), and Serotonin Transporter, new arylpiperazine-containing pyrrole 3-carboxamide derivatives were synthesized and evaluated. Based on the lead reported previously, structural modifications regarding N-(3-(4-(2,3-dichlorophenyl)piperazin-1-yl)propyl)-1,2-dimethyl-5-phenyl-1H-pyrrole-3-carboxamide 5, were accomplished for improvements in not only binding affinity against serotonin receptors and transporter, but also in hERG channel inhibition. Along the line, both the forced swimming tests and spontaneous locomotor activity tests were performed to distinguish between antidepressant activity and false positive results. As potential antidepressant agents, both 2,4-dimethyl-5-phenyl-1H-pyrrole-3-carboxamide and 5-tert-butyl-2-methyl-1H-pyrrole-3-carboxamide derivatives exhibited favorable in vitro and in vivo activities, warranting further investigation around these scaffolds.