Intramolecular Excited State Proton Transfer
Mostrando 1-12 de 15 artigos, teses e dissertações.
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1. Water-Soluble Benzazole Dyes Fluorescent by ESIPT: Structural Characterization, Photophysical Properties and Its Application as a Probe for Direct Staining of Helminths
A series of four water-soluble benzazole dyes that emit fluorescence by the excited state intramolecular proton transfer (ESIPT) mechanism were structurally characterized by Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR) attached proton test (APT) and mass spectrometry. Their photophysical properties were systemat
J. Braz. Chem. Soc.. Publicado em: 2019-03
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2. On the Fluorescent, Steric and Electronic Factors Affecting the Detection of Metallic Ions Using an Imidazolyl-Phenolic Derived Fluorescent Probe
The imidazolyl-phenolic probe used at the present study has its photophysic properties regulated by a tautomeric equilibrium. After the absorption of a photon, an excited state intramolecular proton transfer process generates a ketonic species, responsible for the 440 nm emission (in CH3CN/H2O, 95:5, v/v). Addition of Cu2+, Al3+, Cr3+ and Fe3+ suppresses emi
J. Braz. Chem. Soc.. Publicado em: 2017-10
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3. Synthesis and Photophysical Characterization of Novel ESIPT Triazinyl-Benzazole Derivatives
In this work, the synthesis, characterization and photophysical study of new derivatives of triazinyl-benzazoles with fluorescence by excited-state intramolecular proton transfer (ESIPT) are presented. It regards the synthesis of cyanuric chloride with different 2-(2’-hydroxyphenyl) benzazoles, two quite attractive groups from the synthetic and technologic
J. Braz. Chem. Soc.. Publicado em: 2015-12
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4. Investigation of the Interaction of 2-(2'-Hydroxyphenyl)-benzoxazoles and their Derivatives with B-DNA by Docking and Molecular Dynamics
In this work we carried out a study covering conformational analysis, docking calculations and molecular dynamics (MD) simulations of six excited state intramolecular proton transfer (ESIPT)-fluorescent 2-(2'-hydroxyphenyl)-benzoxazoles, interacting with the Dickerson-Drew (d(CGCGAATTCGCG)2) dodecamer in B-DNA conformation. In the analysis of the molecular d
J. Braz. Chem. Soc.. Publicado em: 2015-03
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5. Síntese de heterociclos benzazolil-quinolínicos como precursores de análogos de nucleosídeos e sondas biológicas fluorescentes via ESIPT
Neste trabalho são apresentadas a síntese e a caracterização de dois heterociclos bifuncionais do tipo benzazolil-quinolínicos, que apresentam as propriedades fotoemissoras dos benzazóis aliadas às potenciais propriedades biológicas das quinolinas. A família dos heterociclos 2-(2`-hidroxifenil)benzazólicos apresenta uma intensa emissão de fluoresc
Publicado em: 2007
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6. Study of the Complexation of Fisetin with Cyclodextrins / Estudo da complexação da fisetina com ciclodextrinas
Neste trabalho de Mestrado, foram feitos estudos do comportamento fotofísico da fisetina em diversos solventes através de medidas de absorção de luz UV-Visível, fluorescência estática e resolvida no tempo e da interação entre fisetina (3,3,4,7-tetrahidroxiflavona) e 7-hidroxiflavona com ciclodextrinas ( beta e gama) (CDs) através de experimentos de
Publicado em: 2007
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7. AplicaÃÃo de mÃtodos correlacionados de estrutura eletrÃnica ao estudo de estados excitados de molÃculas em fase gasosa e em soluÃÃo
Ab-initio electronic structure calculations, at correlated level, are applied to the study of excited states of molecules in gas-phase and solution. The electron correlated methods comprise the multiconfigurational SCF (MCSCF), and the multi-reference CI method with single and double excitations (MR-CISD), which is used in combination with MCSCF, then provid
Publicado em: 2005
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8. Excited-state intramolecular proton transfer as a fluorescence probe for protein binding-site static polarity
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9. Mechanism of four-level laser action in solution excimer and excited-state proton-transfer cases
Four-level laser energy level schemes are compared from the mechanistic spectroscopic viewpoint: (i) noble-gas excimer, (ii) solution molecular excimer, (iii) conventional dye laser, and (iv) intramolecular proton transfer. The lasing action of the chlorophyll special pair is discussed as an example of a solution excimer laser, and the lasing action of 3-hyd
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10. Interplay between excited-state intramolecular proton transfer and charge transfer in flavonols and their use as protein-binding-site fluorescence probes.
A comparative study is presented of competitive fluorescences of three flavonols, 3-hydroxyflavone, 3,3',4',7-tetrahydroxyflavone (fisetin), and 4'-diethylamino-3-hydroxyflavone (DHF). The normal fluorescence S1-->S0 (400-nm region) is largely replaced by the proton-transfer tautomer fluorescence S'1-->S'0 in the 550-nm region for all three of the flavonols
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11. Energy transfer to a proton-transfer fluorescence probe: Tryptophan to a flavonol in human serum albumin
A protein fluorescence probe system, coupling excited-state intermolecular Förster energy transfer and intramolecular proton transfer (PT), is presented. As an energy donor for this system, we used tryptophan, which transfers its excitation energy to 3-hydroxyflavone (3-HF) as a flavonol prototype, an acceptor exhibiting excited-state intramolecular PT
The National Academy of Sciences of the USA.
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12. Ultrasensitive two-color fluorescence probes for dipole potential in phospholipid membranes
The principle of electrochromic modulation of excited-state intramolecular proton-transfer reaction was applied for the design of fluorescence probes with high two-color sensitivity to dipole potential, Ψd, in phospholipid bilayers. We report on the effect of Ψd variation on excitation and fluorescence spectra of two new 3-hydroxyflavone probes, which poss
National Academy of Sciences.