Trinuclear µ-Oxo Ruthenium Complexes with nitrosil and À-acceptor ligands: Synthesis, characterization and interaction studies with biomolecules.

Abstract

This project aims to develop a new series of trinuclear ruthenium complexes (clusters), of the general formula [Ru3O(CH3COO)6(L)2(NO)]PF6 in which L are pyridine ligands with À-acceptor characteristics, for use as controlled releasers of nitric oxide. The implementation of this proposal will contribute significantly to the study of this class of compounds, because currently the literature contains only two articles that report the application of these complexes in the biological area. The derivatives of ruthenium involved in this study will be synthesized according to adjustments of previously reported synthetic routes and they will be characterized by spectroscopic and electrochemical techniques and others, namely: elemental analysis, mass spectrometry, NMR, UV absorption -visible, infrared, cyclic voltammetry and of differential pulse and luminescence. The photoinduced release of nitric oxide from solution at physiological pH will be investigated in the presence and absence of human serum albumin (HSA), by means of spectrophotometric and amperometric monitoring. The quantum yield of NO release in physiological medium will be calculated by chemical actinometry. The interaction between trinuclear ruthenium clusters with biomolecules - HSA and calf thymus DNA - not yet reported in the literature, will be studied by means of spectroscopic techniques such as luminescence and / or UV-visible, at different temperatures therefore will be obtained the values of the thermodynamic parameters G, H and S. The Amino acids, basic units of proteins are important ligands present in biological medium. Therefore, the reactivity of trinuclear ruthenium complexes in aqueous solution of physiological pH with some amino acids of interest will also be studied.