Reactivity and biological properties of asymmetric ruthenium trinuclear complexes with imidazole ligands

• Grant number: 23/08615-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: October 01, 2023
• End date: July 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Sofia Nikolaou
• Grantee: Amanda Batista Silva
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

This project aims to study the reactivity and biological activity of trinuclear ruthenium carboxylates with u-xo bridge of the general formula [Ru3O(CH3COO)6(L)2CO]0, [Ru3O(CH3COO)6(L)2NO]Cl- and [Ru3O(CH3COO)6(L)2(H2O)]Cl-, where L = imidazole(Im), 1-(2-hydroxyethyl)imidazole (2-OHIm), 1-(3-hydroxypropyl)imidazole (3 -OHIm) and imidazole-1-acetic acid (1-AcIm). Reactivity studies will focus on describing the release of CO and NO gaseous transmitters by light, redox and pH stimuli. It is also intended to explore the reactivity of amino acids (histidine and tryptophan), aiming to understand the potential of these complexes to covalently bind to proteins such as albumin. The choice of imidazole ligands intent to make the complexes soluble in water, given that these ligands can form hydrogen bonds with water molecules and also enrich the chemistry of these complexes in aqueous media since the complexes respond to the pH of the medium. The synthesis of the complexes will be carried out based on precedents in the literature, and they will be characterized by electronic and vibrational magnetic spectroscopy, 1H and 13C nuclear resonance (NMR) and elemental analysis, cyclic voltammetry and spectroelectrochemistry. The degree of hydrophilicity of the complexes will be studied by the authority of the specialist coordinators. The acid-base reactivity of the complexes will be tested under different pH conditions, and the stability of the complexes will also be tested at different temperatures. The release of CO and NO oxides will be experienced via redox stimulation with dihydrogen peroxide (for carbonyl complexes) and glutathione and ascorbic acid (for nitrosyl complexes). Finally, the biological activity of the complexes will be determined by cytotoxicity tests against tumor cell lines. (AU)