Preparation of piperazine derivatives as 5-HT7 receptor antagonists Original Research Article

Twenty-four compounds of 4-methoxy-N-[3-(4-substituted phenyl-piperazine-1-yl)propyl] benzene sulfonamides and N-[3-(4-substituted phenyl-piperazine-1-yl)propyl] naphthyl sulfonamides were prepared and evaluated as 5-HT7 receptor antagonists. Most of the compounds showed the IC50 values of 12–580 nM. Four methyl branched analogues were also obtained, but the activity for methyl branched analogues was almost same as its straight chain congeners. Among the synthesized compounds, 3c showed a good activity on 5-HT7 receptors and a good selectivity on 5-HT1a, 5-HT2a, 5-HT2c, and 5-HT6 receptors.