Structure-activity relationship studies of a series of novel 4, 6-disubstituted 2-(1-piperazinyl)pyridines were conducted to revise our model of serotonin 5-HT(2A) receptor antagonist. Target compounds were synthesized using the benzotriazole-assisted Katritzky method. The majority of those compounds were found to be selective 5-HT(2A)/5-HT(1A) receptor ligands, though less potent than their previously described pyrimidine counterparts. In particular, the three compounds 6-8 showed the highest 5-HT(2A) receptor affinity (K(i) = 34-78 nM) and were classified as 5-HT(2A) antagonists in in vivo experiments. The influence of the structural modifications on the in vitro results was discussed; however, the elucidation of the role of the central core system requires further studies.