Banca de DEFESA: THUANNY MOURA DE SOUSA
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.DISCENTE : THUANNY MOURA DE SOUSA
DATA : 02/07/2019
HORA: 14:00
LOCAL: sala 3F6
TÍTULO:
DEVELOPMENT AND REACTIVITY OF RUTHENIUM NITROSYL COMPLEXES WITH POSSIBLE ANTIBACTERIAL ACTION
PALAVRAS-CHAVES:
Nitrosyl complexes. Ruthenium. Pseudomonas aeruginosa. Staphylococcus aureus. Staphylococcus epidermidis
PÁGINAS: 105
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Inorgânica
ESPECIALIDADE: Campos de Coordenação
RESUMO:
The present work aims at the development of nitrosyl ruthenium complexes capable of acting as a donor of nitric oxide in biological systems, considering that this molecule acts in a variety of physiological processes such as neurotransmission, blood pressure regulation and participation in the immune system in the fight against tumor cells and intracellular parasites. For this reason, we present the synthesis, characterization, reactivity and antibacterial assays of cis-[Ru(bpy)(phen)(L)(NO)] (PF6) 3 type complexes where L are the thiourea and 4- nitroimidazole, bpy = 2,2'-bipyridine and phen = 1,10'-phenanthroline. The compounds were obtained from the cis- [Ru(bpy)(phen)Cl2] precursor complex in water and ethanol with addition of the ligands under study. Through the UV-Vis technique, in aqueous solution, it was possible to identify the MCLT bands for the polypyridine linkers as for the nitrosyl linker in the 420-480 nm range. With respect to the infrared spectra, the complexes exhibited bands in 1926 and 1942 cm-1 attributed to ѵ(NO+) with thiourea and 4-nitroimidazole, respectively, indicating the coordination of the nitrosyl ligand. The cyclic voltammograms obtained in NaTFA 0.1 mol / L and pH 3.5 showed E1/2 in 32 mV for the complex with thiourea and 112 mV for 4-nitroimidazole, both referring to the NO+/0 redox pair. Regarding the reactivity, the complexes showed to be able to release the nitric oxide by photochemical reduction and that the nitrosyl nitrite interconversion reaction occurs at pH 6.70 and pH 5.86 for the compounds with thiourea and 4-nitroimidazole, respectively. The antibacterial activity of the nitrosyl complexes was investigated against the bacteria Pseudomonas aeruginosa (ATCC-9027) and the cis-[Ru(bpy)(phen)(TU)(NO)](PF6)3 complex against Staphylococcus aureus bacteria (ATCC- 25923/ATCC-700698) and Staphylococcus epidermidis (ATCC-12228 /ATCC-35984). The test revealed a MIC of 121.5 μM, from the thiourea complex for Pseudomonas aeruginosa (ATCC-9027) and a MIC of 511 μM for the bacteria Staphylococcus aureus (ATCC-25923/ATCC-700698) and epidermidis (ATCC -12228). This indicates that the compound under study has the ability to inhibit the growth of these bacteria. In addition, the compound showed a MBC of 511 μM for Staphylococcus aureus (ATCC-25923) and Staphylococcus epidermidis (ATCC-35984) suggesting it to be an antibacterial agent.
MEMBROS DA BANCA:
Interno - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Externo ao Programa - 1715109 - DANIEL DE LIMA PONTES
Presidente - 1945343 - FRANCISCO ORDELEI NASCIMENTO DA SILVA
Externo à Instituição - TERCIO DE FREITAS PAULO - UFC