Síntese, caracterização e avaliação das propriedades antiepilépticas de Complexos de Paládio (II) derivados do Diazepam

Abstract

Epilepsy is a neurological disease that affects approximately 50 million people worldwide and is related to oxidative stress, which plays an important role in the neuronal damage induced by seizures. The current drugs used in the treatment of this disease have their use often limited due to their adverse effects; moreover, approximately 30% of epileptic patients who are receiving drug treatment are not totally free of seizures. These facts motivated the development of this work that aims to synthesize, characterize and evaluate palladium(II) complexes derived from diazepam in order to obtain complexes that can be used to treat epilepsy. In this work were synthesized five complexes of diazepam-palladium(II): two in dimeric form (DIAZPdOAcD and DIAZPdClD) and three in monomeric form (DIAZPdOAcPPh3, DIAZPdClPPh3 and DIAZPdClPy). All these complexes were characterized by spectrometric techniques and elemental analysis; the monomer DIAZPdOAcD had your chemical structure elucidated by X-ray diffraction. In addition, all complexes were evaluated for anticonvulsant and antioxidante activities and for citotoxicity. Through the characterization techniques used in this work it was possible to confirm the formation of all the complexes; it is important to noted that the X-ray diffraction study of DIAZPdOAcD showed the distorted square-planar geometry of palladium(II), the occurrence of cyclopalladation and the open-book shape of this dimer. Regarding the anticonvulsant and antioxidante activities, it was observed that only the DIAZPdOAcD dimer presented significant results. With respect to cytotoxicity, all complexes showed more pronounced toxicity when compared to diazepam. However, the anticonvulsive effect and the potential neuroprotective effect performed by DIAZPdOAcD should be emphasized, since they are important characteristics of new drugs for the treatment of epilepsy.