Browsing by Author "Silva, Jose Mauricio Schneedorf Ferreira da"

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    2,2’,4-Trihydroxybenzophenone : crystal structure, and anti-inflammatory and antioxidant activities.
    (2007) Doriguetto, Antônio Carlos; Martins, Felipe Terra; Ellena, Javier Alcides; Salloum, Rogério; Santos, Marcelo Henrique dos; Moreira, Maria Eliza de Castro; Silva, Jose Mauricio Schneedorf Ferreira da; Nagem, Tanus Jorge
    The crystal structure of C 2,2’,4-trihydroxybenzophenoneD (¼(2,4-dihydroxyphenyl)(2-hydroxyphenyl) methanone; 1) was determined, and its molecular structure, along with intra- and intermolecular Hbonds, was analyzed. The anti-inflammatory potential of 1, evaluated by means of the rat-paw-edema assay, with carrageenan as inflammation stimulus, was found to be similar high as that of indomethacin. In contrast, benzophenone proper (2) was hardly active in this assay. Our results indicate that these antiinflammatory effects are related to the action of kinins and prostaglandins. The radical-scavenging properties of 1 towards DPPH were found to be similar as those of typical phenolics, but somewhat lower than that of ascorbic acid. The structure–activity relationship (SAR) of 1 is discussed.
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    Phase diagrams of aqueous biphasic micellar systems formed by polyethylene glycol (10,000 or 35,000 g mol -1 ) + triton x-100 + water at different temperatures : experimental and correlation.
    (2020) Machado, Poliana Aparecida Lopes; Alves, Ana Paula Pereira; Costa, Éderson D’Martin; Mageste, Aparecida Barbosa; Silva, Jose Mauricio Schneedorf Ferreira da; Virtuoso, Luciano Sindra
    A wide characterization of the phase equilibrium involved in aqueous biphasic micellar systems (ABMSs) formed by 10,000 or 35,000 g mol−1 polyethylene glycol (PEG) + t octylphenoxypolyethoxyethanol (Triton X-100) + water was evaluated at 283.15, 298.15, and 313.15 K, respectively. The influences of temperature, polymer molar mass, and mixture compositions on the phase diagrams obtained were evaluated. The analysis of the phase diagrams obtained experimentally showed that the increase of temperature favors, significantly, the phase separation process. The increase in the polymer molecular weight from 10,000 to 35,000 g mol−1 has an even more pronounced effect than that of temperature in inducing phase separation. The experimental liquid−liquid equilibrium (LLE) data were then theoretically correlated using the extended Flory−Huggins lattice model for ternary mixtures. The interaction parameters of the component’s pairs PEG−Triton X-100 (λ12), PEG−water (λ13), and Triton X-100−water (λ23) in the ABMSs were estimated at different temperatures and in two different surfactant configurations (single molecule and micellar aggregates). Although it was not possible to correlate the parameters of interaction with the physical reality of ABMSs, the Flory−Huggins model allowed to recover the LLE data within the experimental error range. The experimental data of the binodal curves for the different ABMSs were also adjusted through the Othmer−Tobias, Bancroft, and Setschenow empirical equations.