Síntese de complexos de Mn(III) à base de porfirinas tricatiônicas do Tipo A3B (A = 2-N-metilpiridinio; B = 3-metoxi-4-hidroxifenil ou 3,4-dimetoxifenil) como potenciais mímicos das enzimas superóxido dismutases (SOD)

Detalhes bibliográficos
Ano de defesa: 2016
Autor(a) principal: Sarmento Neto, José Ferreira
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal da Paraíba
Brasil
Química
Programa de Pós-Graduação em Química
UFPB
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: https://repositorio.ufpb.br/jspui/handle/tede/8985
Resumo: The superoxide anion is among the reactive oxygen species closely related to physiopathological states associated with oxidative stress. The physiological superoxide levels are controlled in vivo by the superoxide dismutase enzymes (SOD). Pentacationic Mn porphyrins derived from 2-N-alkylpyridylporphyrins have been explored as potent SOD mimics and efficient redox modulators of oxidative stress. The in vivo efficiency of these compounds is related with their intrinsic catalytic activity, lipophilicity, bioavailability, and toxicity. The present study describes the synthesis of two A3B-type neutral porphyrins of low symmetry (A = 2-pyridyl, B = 3-methoxy-4-hydroxyphenyl or 3,4-dimethoxyphenyl), the methylation of these compounds to yield tricationic porphyrins and the preparation of the corresponding tetracationic Mn(III) porphyrins; overall, 8 new compounds are described: 5-(3-methoxy-4-hydroxyphenyl)-10,15,20-tris(2-pyridyl)porphyrin (H2VanTri-2-PyP), 5-(3,4-dimethoxyphenyl)-10,15,20-tris(2-pyridyl)porphyrin (H2MVanTri-2-PyP), 5-(3-methoxy-4-hydroxyphenyl)-10,15,20-tris(N-methylpiridinium-2-yl)porphyrin chloride (H2VanTriM-2-PyPCl3), 5-(3,4-dimethoxyphenyl)-10,15,20-tris(N-methylpiridinium-2-yl)porphyrin chloride (H2MVanTriM-2-PyPCl3), 5-(3-methoxy-4-hydroxyphenyl)-10,15,20-tris(2-pyridyl)porphinatomanganese(III) (MnVanTri-2-PyPCl), 5-(3,4-dimethoxyphenyl)-10,15,20-tris(2-pyridyl)porphinatomanganese(III) chloride (MnMVanTri-2-PyPCl), 5-(3-methoxy-4-hydroxyphenyl)-10,15,20-tris(N-methylpiridinium-2-yl)porphinatomanganese(III) chloride (MnVanTriM-2-PyPCl4) and 5-(3,4-dimethoxyphenyl)-10,15,20-tris(N-methylpiridinium-2-yl)porphinatomanganese(III) chloride (MnMVanTriM-2-PyPCl4). The spectroscopic, electrochemical properties and lipophilicity of all compounds were compared with A4-type 2-N-pyridyl porphyrin analogues. The monocationic compounds MnVanTri-2-PyP+ and MnMVanTri-2-PyP+ showed too low Mn(III)/Mn(II) reduction potential incompatible with superoxide dismuting activity, whereas the tetracationic complexes MnVanTriM-2-PyP4+ and MnMVanTriM-2-PyP4+ showed potential values suitable for the development these compounds as SOD mimics based on structure-activity relationships reported for analogous systems. The lipophilicity of MnVanTriM-2-PyP4+ and da MnMVanTriM-2-PyP4+ suggests promising bioavailability for in vitro and in vivo testing.