Cationic Porphyrins
Mostrando 1-12 de 19 artigos, teses e dissertações.
-
1. Síntese de meso-tetrafenilporfirinas com substituintes reativos no anel meso-fenil visando a obtenção de derivados porfirínicos catiônicos aquossolúveis
There is a considerable interest in the synthesis of water soluble porphyrins due to its use as models of biological systems, as drugs and as homogeneous catalysts in aqueous media. Within this context, this work describes the synthesis of meso-tetraphenylporphyrins with reactive groups on the meso-phenyl ring to generate trimethylarylammonium salts derivati
Publicado em: 2010
-
2. Tetracationic alkylated porphyrin: Photosensitizers for use in photodynamic therapy of skin cancers / Porfirinas tetracatiônicas alquiladas: sistemas porfirínicos fotossensibilizadores para uso em terapia fotodinâmica do câncer de pele
A series of photosensitizers (PS), which are meso-substituted tetra-cationic porphyrins, was synthesized and characterized in order to study the role of amphiphilicity and zinc insertion in PDT efficacy. The photophysical properties of all compounds are quite similar (absorption maxima in the same region of the spectra, f 0.02; ~0.8). An increase in lipophil
Publicado em: 2009
-
3. Interaction of hidrophilic porphyrins and extracellular hemoglobin with biomimetic models of biological membranes / Interação de porfirinas hidrofílicas e de hemoglobina extracelular com modelos biomiméticos de membrana biológica
In the first part of this work interactions of the cationic meso tetrakis (4-N-methilpyridil) porphyrin (TMPyP) and meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS4) in the free base forms with membrane model systems (ionic micelles, mixed micelles and phospholipids vesicles) in aqueous solutions, have been investigated by optical absorption, resonance lig
Publicado em: 2008
-
4. Photodynamic action of mesoporphyrins on mitochondrial functions and LNCaP cell viability / Ação fotodinamica de meso-porfirinas sobre função mitocondrial e viabilidade de celulas LNCaP
The action of irradiated cationic Fe(III)TMPyP and anionic Fe(III)TPPS4 forms of mesoporphyrins on mitochondrial functions was investigated using experimental conditions that caused minimal effects on mitochondria in the dark. Treatment of mitochondria with 1 µM Fe(III)TMPyP for 2 min decreased the respiratory control by 3% in the dark and 28% after irradia
Publicado em: 2006
-
5. MECANISMOS DE NITROSILAÇÃO DE FERRO PORFIRINAS POR SNAP: CINÉTICA DE REAÇÃO E ESTABILIDADE EM AMBIENTE AERÓBICO / MECHANISMS OF NITROSYLATION OF IRON PORPHYRINS BY SNPA: KINETICS OF THE REACTION AND STABILITY UNDER AEROBIC ENVIRONMENT
Serveal metalic complexes have been identified as tergets for the binding of nitric oxide. In order that these complexes can be efficiently and safely used in medical applications, it is important to understand their kinetic and structural properties in realistic models. In this work, the optical absorption and electron paramagnetic resonance techniques were
Publicado em: 2006
-
6. Synthesis and properties of supermolecular meso tetra(pyridyl)porphyrins and its layer-by-layer electrostatic assembled nanomaterials / Obtenção e propriedades de meso tetra(piridil)porfirinas supermoleculares e dos nanomateriais obtidos por montagem eletrostática camada por camada
A new series of nonplanar supermolecular metalloporphyrins have been obtained by coordenative self-assembly of meso-tetra(3-pyridyl)porphyrins and ruthenium complexes such as [Ru(bipy)2Cl]+ and [Ru(bipy)2(OH2)]2+. The electronic and structural properties have been investigated by electronic spectroscopy, mass spectrometry, cyclic voltammetry, and spectroelec
Publicado em: 2005
-
7. Estudo da interação entre porfirinas e eumelanina sintética / Study of porphyrin-synthetic eumelanin interaction
Foram investigadas através da técnica de absorção eletrônica Uv-Vis e emissão de fluorescência a interação entre uma série de porfirinas e zinco-porfirinas com o polímero de eumelanina sintética obtida pela auto-oxidação da L-DOPA (dihidroxi-fenilalanina). Ocorre a formação de dois complexos na interação entre as porfirinas catiônicas e a
Publicado em: 2005
-
8. Porphyrins derivatives as photosensitizers for photodynamic therapy / Derivados porfirínicos como fotossensibilizadores para terapia fotodinâmica
Nesta tese serão discutidos alguns aspectos químicos, fotoquímicos e fotofísicos importantes no desenvolvimento de fotossensibilizadores para aplicação em terapia fotodinâmica (TFD). Os estudos abrangeram a investigação de 29 espécies, sendo que 20 delas continham um anel porfirínico convencional e 9 eram porfirinas duplamente N-confusas. As prime
Publicado em: 2005
-
9. The effect of porphyrins on normal and transformed mouse cell lines in the presence of visible light
Photodynamic therapy consists of the uptake of a photosensitizing dye, often a porphyrin, by tumor tissue and subsequent irradiation of the tumor with visible light of an appropriate wavelength matched to the absorption spectrum of the photosensitizing dye. This class of molecules produces reactive oxygen species when activated by light, resulting in a direc
Brazilian Journal of Medical and Biological Research. Publicado em: 2001-10
-
10. DNA intercalation and photosensitization by cationic meso substituted porphyrins.
Several cationic porphyrins are known to bind to DNA by intercalative and outside binding modes. This study identifies the cis and trans isomers of bis(N-methyl-4-phridiniumyl)diphenyl porphyrin as DNA intercalators based on evidence from a DNA topoisomerase I assay. Moreover, both isomers are shown to be potent photosensitizers of DNA, inducing multiple S1
-
11. Influence of the nature of the porphyrin ligand on the nuclease activity of metalloporphyrin-oligonucleotide conjugates designed with cationic, hydrophobic or anionic metalloporphyrins.
The synthesis of metalloporphyrin-oligonucleotide conjugates with different metalloporphyrin moieties are described as well as the comparison of their in vitro nuclease efficiency toward a single-stranded DNA target. Between cationic, anionic and hydrophobic manganese porphyrins covalently linked to the oligonucleotide, the best nuclease activity was obtaine
-
12. Cationic porphyrins: novel delivery vehicles for antisense oligodeoxynucleotides.
Cationic porphyrins form stable complexes with oligodeoxynucleotides. To evaluate delivery, we used a 20mer phosphorothioate oligomer (Isis 3521) targeted to the 3'-untranslated region of the PKC-alpha mRNA, and complexed it with porphyrin. The expression of PKC-alpha protein and mRNA in T24 bladder carcinoma cells was reduced by approximately 80 +/- 10% at