Navegando por Autor "Macedo, Adriana Pereira Mundim Guedes"
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Item Esterification of the free carboxylic group from the lutidinic acid ligand as a tool to improve the cytotoxicity of Ru(II) complexes.(2019) Araujo Neto, João Honorato de; Colina Vegas, Legna Andreina; Correa, Rodrigo de Souza; Macedo, Adriana Pereira Mundim Guedes; Miyata, Marcelo; Pavan, Fernando Rogério; Ellena, Javier Alcides; Batista, Alzir AzevedoIn this study, we report on the selective esterification of the carboxyl group in a coordinated ligand based on the Fischer reaction. The new [Ru(N–O)(bipy)(dppb)]PF6 complex 1 was used as a precursor to obtain the ester derivative [Ru(N–Oet)(bipy)(dppb)]PF6 (2), and in order to establish the influence of either the free carboxyl group or the ethoxycarbonyl group on biological properties, the [Ru(pic)(bipy)(dppb)]PF6 complex (3) was synthesized for comparison (dppb = 1,4-bis(diphenylphosphino)butane, bipy = 2,2′-bipyridine, N–O = mono-deprotonated 2,4-pyridinedicarboxylic acid, N–Oet = 4-ethoxycarbonyl-2-pyridinecarboxylic acid). All three complexes interact weakly with human serum albumin (HSA) with Kb values ranging from 101–104 M−1, suggesting a spontaneous interaction with this protein by electrostatic (1–2) or van der Waals interactions (3). Moreover, complex/DNA-binding experiments indicate that complexes 2 and 3 interact weakly with DNA, while no interaction is observed between complex 1 and DNA, probably due to the repulsion involving the free carboxylate group/DNA-phosphate. Anti-Mycobacterium tuberculosis (MTB) activity and cytotoxicity assays against one normal cell line V79 (hamster fibroblast) and three human cancer cell lines A549 (lung), MCF7 and MDA-MB-231 (breast) revealed that complexes 2 and 3 exhibit good activity against MTB and tumor cells, presenting high cytotoxicity (low IC50). On the other hand, complex 1 is practically inactive. Therefore, the best biological results found for complex 2 can be attributed to its esterification, improving the lipophilicity and cellular uptake, in order to facilitate its passive permeation through the tumor cell membranes allowing for cell death, as well as DNA and HSA interactions, when compared with complex 1.Item Nitrosyl/Diphenylphosphine/Amino Acid–Ruthenium complexes as inhibitors of MDA-MB-231 breast cancer cells.(2023) Barbosa, Marília Imaculada Frazão; Correa, Rodrigo de Souza; Macedo, Adriana Pereira Mundim Guedes; Graça, Alex Marchezini; Andrade, Francyelli Mello; Leite, Celisnolia Morais; Lacerda, Elisângela de Paula Silveira; Ellena, Javier Alcides; Silva, Henrique Vieira Reis; Doriguetto, Antônio Carlos; Batista, Alzir AzevedoHerein, we report on the synthesis and characterization of ruthenium compounds with the general formula [RuCl(AA-H)(NO)(dppb]PF6 , where AA = glycine (1), L-alanine (2), L-phenylalanine (3) and L-valine (4), and dppb = 1,4-bis(diphenylphosphine)butane. The complexes were characterized using elemental analysis, UV/Vis and infrared spectroscopies, 1H, 13C, 31P NMR techniques, and cyclic voltammetry. Furthermore, the structures of the compounds (1) and (3) were determined using single-crystal X-ray diffraction. In vitro evaluation of the Ru(II)/nitrosyl/amino acid complexes revealed their cytotoxic activities against triple-negative MDA-MB-231 breast cancer cells, and against the non-tumor murine fibroblast cells. All the compounds decreased the percentage of viable cells, inducing cell death by apoptosis. Additionally, the Ru(II) complexes inhibited the migration of MDA-MB-231 cells at concentrations lower than 35 µM, after 48 h of exposure. Thus, these complexes may be promising agents for the treatment of triple-negative MDA-MB-231 breast cancer.