Novel olanzapine analogues presenting a reduced H 1 receptor affinity and retained 5HT 2A/D 2 binding affinity ratio

Abstract

Background: Olanzapine is an atypical antipsychotic drug with high clinical efficacy, but which can cause severe weight gain and metabolic disorders in treated patients. Blockade of the histamine 1 (H 1) receptors is believed to play a crucial role in olanzapine induced weight gain, whereas the therapeutic effects of this drug are mainly attributed to its favourable serotoninergic 2A and dopamine 2 (5HT 2A/D 2) receptor binding affinity ratios.Results: We have synthesized novel olanzapine analogues 8a and 8b together with the already known derivative 8c and we have examined their respective in vitro affinities for the 5HT 2A, D 2, and H 1 receptors.Conclusions: We suggest that thienobenzodiazepines 8b and 8c with lower binding affinity for the H 1 receptors, but similar 5HT 2A/D 2 receptor binding affinity ratios to those of olanzapine. These compounds may offer a better pharmacological profile than olanzapine for treating patients with schizophrenia. © 2012 Jafari et al.; licensee BioMed Central Ltd.