Synthesis of coumarin derivative using polymer supported reagents

Recently, there has been a surge in use of polymer-supported reagents and catalysts become common tools for organic synthesis in what is known as polymer-assisted synthesis since they can simplify product isolation and purification. In this context, coumarin derivative 3 was prepared in good yield and high purity, starting from 3-methoxy salicylaldehyde, using reagents supported on a macroporous ion exchange resin. For this purpose, iminocoumarin and unsaturated nitrile were used as starting materials. The synthesized compounds were characterized by IR, NMR and mass spectrometry

L’évaluation de dosage phytochimique en flavonoïdes et flavonols des feuilles de pêcher (Prunus persica L.)

Dans le but de valoriser les plantes à caractère médicinal et au regard de leur impact sur la santé, nous nous sommes intéressés à l’étude phytochimique de Prunus persica (L.) une plante réputée en médecine traditionnelle pour ces effets diurétique. . L'étude expérimentale a porté essentiellement sur trois extraits (méthanol/eau, acétate d'éthyle, aqueux) des feuilles de Prunus persica (L.) obtenues par la méthode traditionnelle: macération. Les rendements sont: 13,50%, 0,45%, et 8,20% pour les trois fractions mentionnées précédemment respectivement. La fraction de méthanol/eau représente le rendement le plus élevé par contre la fraction aqueux a montré le rendement le plus faible. Ensuite, nous avons réalisé la quantification des flavonoïdes, et des flavonols dans les trois extraits. Les résultats obtenus montrent que la teneur en flavonoïdes s’est retrouvée élevé dans l'extrait d’acétate d’éthyle (311,71 ± 4,35mg EQ/g ES), et était la même pour le cas des flavonols avec une teneur élevée dans l'extrait d’acétate d’éthyle estimée à (25,28 ± 1,51mg EQ/g ES). Du fait du potentiel thérapeutique de cette plante médicinale, des études complémentaires seront nécessaires pour rendre ce travail exploitable dans le cadre de la mise au point d’un phytomédicament. Les mots clés: .Prunus persica (L.), médecine traditionnelle, flavonoïdes, flavonols

Synthesis and Ionic Conductivity of Phosphate-Sulfate Fluorapatites Ca10-xNax(PO4)6-x(SO4)xF2 (x = 0;3;6)

Abstract BackgroundSolid-state electrolytes for Solid Oxide Fuel Cells (SOFC) with high ionic conductivities has attracted great interest for electrochemical applications because of their interesting ionic conduction. MethodsComples impedance spectroscopy (CIS) was used to study the electrical properties of Phosphate-sulfatefluorapatite.FindingsPhosphate-sulfatefluorapatite Ca10-xNax(PO4)6-x(SO4)xF2(x = 0;3;6) ,have been synthesized by the solid-state reaction at high temperature.The samples have been characterized by X-ray Diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), Raman scattering spectroscopy, and Transmission Electron Microscopy (TEM) techniques. XRD study shows that these materials crystallize in the hexagonal system with P63/m as a space group. An impedance analysis has been used to analyze the electrical behavior of the samples at different temperatures. Evidence of temperature-dependent electrical relaxation phenomena is observed. The bulk resistance decreases with increasing temperature, showing a typical negative temperature coefficient of resistance (NTCR).Ac-conductivity measurements have been performed on a wide range of frequencies and temperatures. The ionic conductivity follows the Arrhenius and the Jonscher laws.</jats:p

Ionic conductivity of apatite-type solid electrolyte ceramics Ca2−xBaxLa4Bi4(SiO4)6O2 (0≤x≤2)

A complex impedance of oxyapatites Ca2-xBaxLa 4Bi4(SiO4)6O2 (0≤x≤2) prepared by solid state reaction has been investigated. The formation of apatites has been checked by X-ray diffraction, FTIR, Raman and 29Si MAS-NMR techniques. The electric impedance data indicate that relaxation phenomena are strongly dependent on temperature in the 923-1048 K range. The bulk resistance decreases with increasing temperature, showing a typical negative temperature coefficient of resistance (NTCR). ac-Conductivity measurements have been performed on a wide range of frequencies and temperatures. The complex modulus plots have confirmed the presence of bulk contributions. The complex impedance analysis suggests the presence of non-Debye relaxations that would be associated with correlation on ions motion. © 2013 Elsevier Ltd and Techna Group S.r.l.Peer Reviewe