14 research outputs found

    Red-Emitting Tetracoordinate Organoboron Chelates: Synthesis, Photophysical Properties, and Fluorescence Microscopy

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    Seven tetracoordinate organoboron fluorophores with heterobiaryl N,O- or N,N-chelate ligands were prepared and photophysically characterized (in toluene). The electronic variation of the heteroaromatic moiety provided a means for the fine-tuning of the UV/vis absorption and emission spectra. In the most interesting cases, the spectra were red-shifted to maximum absorbance at wavelengths longer than 500 nm and emission maxima between 620 and 660 nm. The pronounced intramolecular charge-transfer character of the dyes yielded large Stokes shifts (3500-5100 cm), while maintaining appreciable fluorescence quantum yields of up to 0.2 for emission maxima longer than 600 nm. The lipophilic character of the dyes enabled their application as stains of vesicle substructures in confocal fluorescence microscopy imaging.Ministerio de Economía y Competitividad CTQ2014-54729 - C2 - 1 - P for U.P., CTQ2013 - 48164 - C2 - 1 - P , CTQ2013 - 48164 - C2 - 2 - P for A.R., CTQ2013 - 41339 - P, CTQ2015 - 71896 - REDT for E.P.I., Ramón y Cajal contract RYC - 2013 - 12585 for A.R.FEDER FundJunta de Andalucía 2012/FQM - 2140 for U.P., 2009/FQM - 4537 and 2012/FQM - 1078 for A.R

    Medication adherence predictors in epilepsy: longitudinal study

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    Introdução: A não adesão à medicação na epilepsia é prevalente, pelo que a compreensão dos fatores associados deve ser promovida. Objetivos: Analisar a capacidade preditiva das estratégias de coping e da espiritualidade em relação à adesão à medicação ao longo do tempo. Metodologia: Foram avaliados 60 indivíduos através de um Questionário Sociodemográfico e Clínico, a Medida de Adesão aos Tratamentos, o COPER e a Escala de Avaliação de Espiritualidade em Contextos de Saúde, em dois momentos. Resultados: A espiritualidade Momento 1 não se relacionou com adesão à medicação no Momento 3, e as estratégias de coping: Desinvestimento Comportamental e Aceitação no Momento 1 predizem negativamente a adesão à medicação no Momento 2. Conclusão: A relação entre a adesão à medicação, estratégias de coping e espiritualidade varia em função do tempo, o que deve ser considerado ao nível da intervenção.ABSTRACT - Introduction: The nonmedication adherence in epilepsy is prevalent by which the understanding of associated factors should be promoted. Objectives: To analyze the predictive capacity of the coping strategies and spirituality in relation to medication adherence over time. Methodology: A sociodemographic and clinical questionnaire, medical adherence to treatment, COPER and spirituality evaluation scale in health contexts was undertaken to evaluate 60 individuals with epilepsy, in three moments. Results: Spirituality at Moment 1 is not related to medication adherence at Moment 3, and the coping strategies: behavioral disinvestment and acceptance at Moment 1 predict medication adherence at moment 2. Conclusion: The relation between medication adherence, coping strategies and spirituality change according to time, which should be considered on the level intervention

    Supramolecular control of phthalocyanine dye aggregation

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    A phthalocyaninato zinc(II) dye with four peripheral N-methylpyridinium anchor groups and its higher-order complex with cucurbit[7] uril were photophysically characterised. The supramolecular host-guest interaction with the anchor yielded a deaggregation of the dye in neutral water solutions. This was signalised by the formation of a sharp UV-vis absorption band at ca. 690 nm and a dramatic increase in the fluorescence. While the aggregated dye is essentially non-fluorescent (Phi(f)1x10(3) M-1 for Ca2+, Sr2+, Eu3+)

    Los colorantes organoborónicos derivados de arilisoquinolina con un esqueleto de triarilo muestran fluorescencia dual

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    Se prepararon cuatro nuevos colorantes que derivan de arilisoquinolinas boryiladas, que contienen un tercer residuo de arilo (naftilo, 4-metoxinaftilo, pirenilo o antrilo) que se une a través de un eje estereogénico adicional. Los núcleos de triarilo se sintetizaron mediante acoplamientos Suzuki y luego se transformaron en ésteres de ácido borónico empleando una reacción catalizada por Ir (I). Los cromóforos muestran un comportamiento de emisión dual, donde la banda de emisión de longitud de onda larga puede alcanzar máximos cercanos a 600 nm en solventes polares. Los rendimientos cuánticos de fluorescencia de los colorantes están generalmente en el rango de 0.2-0.4, alcanzando en algunos casos valores tan altos como 0.5-0.6. La fotólisis con flash láser proporcionó evidencia de la existencia de estados triplete excitados. Los colorantes forman complejos de fluoroboronato con aniones fluoruroFour new dyes that derive from borylated arylisoquinolines were prepared, containing a third aryl residue (naphthyl, 4-methoxynaphthyl, pyrenyl or anthryl) that is linked via an additional stereogenic axis. The triaryl cores were synthesized by Suzuki couplings and then transformed into boronic acid esters by employing an Ir(I)-catalyzed reaction. The chromophores show dual emission behavior, where the long-wavelength emission band can reach maxima close to 600 nm in polar solvents. The fluorescence quantum yields of the dyes are generally in the range of 0.2–0.4, reaching in some cases values as high as 0.5–0.6. Laserflash photolysis provided evidence for the existence of excited triplet states. The dyes form fluoroboronate complexes with fluoride anions, leading to the observation of the quenching of the long-wavelength emission band and ratiometric response by the build-up of a hypsochromically shifted emission signalSpanish Ministry of Economy, Industry, and Competitiveness (CTQ2014-54729-C2-1-P for U.P., CTQ2013- 48164-C2-1-P and CTQ2013-48164-C2-2-P for A.R.)Spanish Ministry of Science, Innovation, and Universities (CTQ2017-89832-P for U.P., CTQ2016- 78875-P for M.C.J., and CTQ2017-89416-R for I.V.)European Research and Development Fund, and the Andalusian Government (2012/FQM-2140 for U.P., 2009/FQM-4537 and 2012/FQM-1078 for A.R

    SYNTHESIS AND CHARACTERIZATION OF NOVEL OCTAHEDRAL [FeH(DPPE)2(NCR)][PF6] COMPOUNDS

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    Organometallic compounds have been extensively studied in search of new materials with enhanced NLO properties due to their large hyperpolarizabilities, fast response times and architectural flexibility. Organometallic molecules with a highly polarisable π-conjugated backbone with an electron-donor (D) and an -acceptor (A) groups attached to opposite ends can a large second-order nonlinear susceptibility [1]. In the search of new systems, we synthesised iron(II) octahedral complexes with the general formula [FeX(biphosphine)2(NCR)](PF6) (X=Cl, I or H; bisphosphine=DMPE, DPPE, dppen, odppb; NCR=mono- or dinitrobenzonitriles) with interesting results towards NLO properties [2,3]. In this communication, we report the synthesis and characterization of a series of [FeH(DPPE)2(NCR)](PF6) derivatives. The acceptor capacity of the nitrile chromophore was changed due to the position (ortho and para) of the nitro group and with the change in length of the conjugated backbone. The results were analysed to evaluate the electronic richness of the metal centre and the influence of the structural changes of the coordinated nitrile, which may give some contribution to understand the relationships between structure and NLO responses

    Synthesis and characterization of nitrile ligands towards molecular wires

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    Molecular wires are molecular systems fully conjugated, bearing terminal functionalities for adhesion to microscopic metallic leads. These molecular systems possess numerous interesting physical properties, including electronic properties. Homo- and heterobinuclear complexes with fully conjugated bridges have attracted special attention as they serve as models for metal-metal electronic communication. Here we present the synthesis and characterization of ligands, with nitrile groups as terminal functionalities, which will be complexed to iron and ruthenium moieties. These ligands were synthesized from the (triphenylphosphoranylidene)acetonitrile and 4-cianobenzyltriphenyl-pshosphonium bromide, used as phosphorus ylides to react with aldehydes, in usual Wittig conditions. Their characterization was done by usual spectroscopic methods. It is presented the molecular and crystalline structures of four compounds obtained by X-Ray crystallography (Figure 1). Ratio isomers and yields obtained by these reactions will be compared with other synthetic methodologies also used in the synthesis of these ligands
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