Anxiolytic Properties of Derivatives of 1-Methoxycarbonylmethyl-3-Arylamino-7-Bromo-5- Phenyl-1,2-Dihydro-3H-1,4-Benzodiazepin-2-one

Abstract

TSPO receptors are peripheral benzodiazepine receptors (PBDRs). Unlike central benzodiazepine receptors (CBDRs), PBDRs (TSPO receptors) are widely presented in organs and tissues of animals and humans; these receptors are involved significantly in the regulation of many physiological processes in the norm and pathologies. Elucidation of the molecular bases of interactions between the TSPO receptors and their ligands is an important task of modern pharmacochemistry. We studied the anxiolytic properties of some derivatives of 1-methoxycarbonylmethyl-3-arylamino-7-bromo-5-phenyl-1, 2-dihydro-3H-1,4-benzodiazepin-2-one (compounds 1-7), which demonstrate considerable affinity for TSPO and CBDRs. The anxiolytic activity was estimated in experiments on rats in the “Conflict situation” test, while the intensity of motor activity was estimated in the standard “Open field” test. All tested compounds demonstrated a rather high selectivity in binding with TSPO receptors; compounds 1–4 manifested significant anxiolytic properties. Compound 2 demonstrated the maximum anxiolytic activity; after binding with TSPO receptors, Ki(TSPO) = 19, while Ki(CBDRs) > 10000 nM. All studied compounds were characterized by low toxicity; their LD50 exceeded 500 mg/kg.