Conformational analysis of tandospirone in aqueous solution: lead evolution of potent dopamine D4 receptor ligands

The significant contribution of folded conformation (2) of the anxiolytic tandospirone (1) in aqueous solution was verified by dynamic 1H NMR. A structurally rigid mimic of 2 was designed and synthesized to evaluate the implication of 2 towards neuroleptic receptor binding. The designed structures provided a new rigid scaffold for dopamine D4 ligands.