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1.
Braz. j. med. biol. res ; 51(1): e6858, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889001

RESUMO

A novel heterometallic metal-porphyrinic framework (MPFs) built from Y and K ions as nods and meso-tetra(4-carboxyphenyl)porphyrin as linkers has been successfully synthesized and characterized. The single crystal X-ray diffraction indicated that this complex 1 exhibited a bilayered architecture of the porphyrins, which is seldom seen in MPFs. In addition, in vitro anticancer activity of complex 1 on three human breast cancer cells (BT474, SKBr-3 and ZR-75-30) was further determined.


Assuntos
Humanos , Porfirinas/química , Neoplasias da Mama/tratamento farmacológico , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Valores de Referência , Sais de Tetrazólio , Reprodutibilidade dos Testes , Cristalografia por Raios X , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Formazans
3.
Indian J Exp Biol ; 2002 Feb; 40(2): 192-201
Artigo em Inglês | IMSEAR | ID: sea-62670

RESUMO

Low temperature fluorescence spectra (FS) and fluorescence excitation spectra (FES) of protoporphyrin IX (Proto), Mg-protoporphyrin IX and its monomethyl ester (MgProto-ME) and protochlorophyllide (Pchlide) in etiolated barley leaves treated with 5-aminolevulinic acid and/or 2,2'-dipyridyl were studied. The spectra of Proto and MgProto-ME showed a little dependence on temperature of registration and exhibited similarity to low temperature spectra in diluted organic and buffer solutions. However, a red wavelength shift for Soret bands of Proto and MgProto-ME was observed due to porphyrin interaction with bovine serum albumin in 0.05 M, Na2HPO4 solution at room temperature. Disaggregating treatments had no effect on Proto and MgProto-ME spectra in plants. These results suggested that in etiolated leaves Proto and MgProto-ME molecules were in a monomer state. The spectral properties of these molecules were determined by interaction of porphyrins with proteins and other plastid membrane components. The spectral analyses indicated an efficient energy migration from Proto and MgProto-ME molecules to active form of Pchlide which emitted at 656nm, and no energy transfer from carotenoids to porphyrins in vivo. These findings suggested that Proto and MgProto-ME from carotenoids, and close location of these porphyrins and photoactive Pchlide in etioplast membranes. The latter conclusion was strongly supported by an observation that in etiolated leaves, S-adenosyl-L-methionin:Mg-protoporphyrin IX methyltransferase, which converts MgProto into MgProtoME, were located not only in prothylakoids but also in prolamellar bodies containing photoactive Pchlide.


Assuntos
Clorofila/química , Hordeum/metabolismo , Metiltransferases/química , Folhas de Planta/metabolismo , Porfirinas/química , Conformação Proteica , Espectrometria de Fluorescência/métodos , Espectrofotometria , Temperatura , Fatores de Tempo
4.
An. acad. bras. ciênc ; 72(1): 27-32, mar. 2000.
Artigo em Inglês | LILACS | ID: lil-259474

RESUMO

A relevant series of symmetric supramolecular porphyrins has been obtained by attaching four [RuII(bipy)2Cl] groups to the pyridyl substituents of meso-tetra(4-pyridyl)porphyrin and its metallated derivatives. These compounds display a rich electrochemistry and versatile catalytic, electrocatalytic and photochemical properties, associated with the ruthenium-bipyridine and the porphyrin complexes. These properties can be transferred to the electrodes by attaching thin molecular films of the compounds, by dip-coating, electrostatic assembly or electropolymerization. In this way, the interesting properties of those supermolecules and supramolecular assemblies can be used to prepare molecular devices and sensors


Assuntos
Técnicas Biossensoriais/métodos , Porfirinas/química , Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Substâncias Macromoleculares , Espectrometria de Massas , Compostos de Rutênio/química
5.
An. acad. bras. ciênc ; 72(1): 45-9, mar. 2000.
Artigo em Inglês | LILACS | ID: lil-259477

RESUMO

Two-dimensional inorganic networks can shown intracrystalline reactivity, i.e., simple ions, large species as Keggin ions, organic species, coordination compounds or organometallics can be incorporated in the interlayer region. The host-guest interaction usually causes changes in their chemical, catalytic, electronic and optical properties. The isolation of materials with interesting properties and making use of soft chemistry routes have given rise the possibility of industrial and technological applications of these compounds. We have been using several synthetic approaches to intercalate porphyrins and phthalocyanines into inorganic materials: smectite clays, layered double hydroxides and layered niobates. The isolated materials have been characterized by elemental and thermal analysis, X-ray diffraction, surface area measurements, scanning electronic microscopy, electronic and resonance Raman spectroscopies and EPR. The degree of layer stacking and the charge density of the matrices as well their acid-base nature were considered in our studies on the interaction between the macrocycles and inorganic hosts.


Assuntos
Compostos Inorgânicos/química , Substâncias Intercalantes , Hidróxidos/química , Metaloporfirinas/química , Porfirinas/química
6.
An. acad. bras. ciênc ; 72(1): 59-66, mar. 2000.
Artigo em Inglês | LILACS | ID: lil-259479

RESUMO

New materials porphyrinosilica and metalloporphyrinosilica template have been obtained by a sol-gel processing where functionalyzed porphyrins and metalloporphyrins "building blocks" were assembled into a three-dimensional silicate network. The optimized conditions for preparation of these materials are reviseed. The monomer precursors porphyrinopropylsilyl and metalloporphyrinopropylsilyl preparation reactions and subsequent one pot sol-gel processing with tetraethoxysilane are discussed. In the case of metalloporphyrins the nitrogen base coordinates to the central metal and acts as a template in the molecular imprinting technique. UV-visible absorption spectroscopy, thermogravimetric analysis, electron paramagnetic resonance, nuclear magnetic spectra, infrared spectra, luminescence spectra, surface area and electron spectroscopy imaging of the materials are used to characterize the prepared materials. The catalytic activities of these metalloporphyrinosilica-template are compared.


Assuntos
Metaloporfirinas/metabolismo , Porfirinas/metabolismo , Silicatos , Catálise , Géis , Metaloproteínas/química , Metaloproteínas/metabolismo , Porfirinas/química
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