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Youssef C.,University of Sfax | Ammar H.B.,University of Sfax | Ammar H.B.,Laboratoire Of Chimie Organique Appliquee | Belhouchet M.,University of Sfax | And 4 more authors.
Journal of Heterocyclic Chemistry | Year: 2011

2-(Arylidene)cyanomethylbenzoxazoles have been prepared in water from benzoxazole-2-ylacetonitriles. Using multi-component reactions, a variety of heterocycles containing benzoxazole and nitrile functionality has been prepared. © 2011 HeteroCorporation.


Bendjeddou A.,Laboratoire Of Chimie Organique Appliquee | Abbaz T.,University of Tébessa | Regainia Z.,Laboratoire Of Chimie Organique Appliquee | Aouf N.-E.,Laboratoire Of Chimie Organique Appliquee
Molecules | Year: 2012

This work reports the synthesis of novel 1,4,3,5-oxathiadiazepanes 4,4-dioxides from the reaction of N'-benzyl-N-(2-hydroxyethyl)-sarcosine or proline sulfamide with aromatic aldehydes under acid catalysis. To prepare the starting materials N-Boc-sulfamide derivatives of sarcosine or proline were alkylated with benzyl alcohol under Mitsunobu reaction conditions, the Boc group was removed chemoselectively by acidolysis, and the resulting product reduced to the corresponding alcohol in good yields.


Tazi S.,Laboratoire des Materiaux et Systemes Interfaciaux | Raissouni I.,Laboratoire des Materiaux et Systemes Interfaciaux | Chaoukat F.,Laboratoire des Materiaux et Systemes Interfaciaux | Bouchta D.,Laboratoire des Materiaux et Systemes Interfaciaux | And 3 more authors.
Journal of Materials and Environmental Science | Year: 2016

In recent decades, Natural substances were intensively studied in order to determine their active compounds that have found its application in food and medical-sciences. The growing interest in such substances diversifies its applications including as anti-corrosion substances. Indeed, interesting results were obtained with essential oils as materials protection for metals, beside these natural inhibiters were recognized as not toxic elements and therefore do not present risks for environmental pollution compared to the organic inhibiters. In this work, we studied the effect of essential oil of clove (recognized in medical field by its analgesic and antiseptic properties) on the corrosion of brass (70%Cu/30%Zn) in NaCl 3%. The results obtained showed a improvement of alloy resistance against salt corrosion. In order to determine the most active component of this essential oil, that plays a key role in inhibiting corrosion of this alloy, the eugenol was extracted from the essential oil of clove. The effect of concentration, temperature and the immersion time were studied to measure the inhibiting capacity of eugenol by using polarization and electrochemical impedance spectroscopy (EIS).


Feau C.,Laboratoire Of Chimie Organique Appliquee | Klein E.,Laboratoire Of Chimie Organique Appliquee | Kerth P.,Preventor TBC GmbH | Lebeau L.,Laboratoire Of Chimie Organique Appliquee
Synthetic Communications | Year: 2010

A series of 14 new 3-alkoxycarbonyl 6-aza-, 7-aza-, and 6,8-diaza-coumarins was prepared using various strategies involving either a Knoevenagel or a Pechmann condensation reaction. The coumarin nucleus displays different reactive functional groups allowing straightforward derivatization. The optical properties of the new azacoumarins were measured in methanol. Copyright © Taylor & Francis Group, LLC.


Ben Ammar H.,Laboratoire Of Chimie Organique Appliquee | Ben Ammar H.,CNRS Chemistry Institute of Rennes | Miao X.,CNRS Chemistry Institute of Rennes | Fischmeister C.,CNRS Chemistry Institute of Rennes | And 2 more authors.
Organometallics | Year: 2010

The reaction of [RuCl 2(p-cymene)] 2 with benzoxazoleacetonitriles and NH 4 +BF 4 - in methanol leads to bidentate N,N′-benzoxazole-methoxyimine- ruthenium(II) complexes 7, corresponding to the addition of methanol to the ruthenium(II)-activated nitrile triple bond. The X-ray structure of a complex 7 shows equivalent Ru-N and slightly different C=N bond distances. The catalytic hydration of benzoxazolacetonitriles with [RuCl 2(p-cymene)] 2 in methanol/water leads to quantitative formation of corresponding amides under mild conditions. © 2010 American Chemical Society.


Ammar H.B.,Laboratoire Of Chimie Organique Appliquee | Hassine B.B.,University of Monastir | Fischmeister C.,CNRS Chemistry Institute of Rennes | Dixneuf P.H.,CNRS Chemistry Institute of Rennes | Bruneau C.,CNRS Chemistry Institute of Rennes
European Journal of Inorganic Chemistry | Year: 2010

Imidazolium-oxazoline chlorides have been prepared from chloroacetonitrile and used to generate bidentate mixed NHC-oxazoline ligands for ruthenium-catalyzed substitution of cinnamyl chloride by phenols. These ligands associated to [RuCp*(MeCN)3][PF6] promote allylic substitution reactions at room temperature with high regioselectivity in favour of the branched isomers giving terminal alkenes. These allylic ethers have been involved in further ruthenium-catalyzed cross metathesis reactions with electron-deficient olefins to give unsaturated esters and aldehydes. NHC-oxazoline ligands associated to the Cp*RuII moiety generate catalysts that orientate the nucleophilic allylic substitution of cinnamyl chloride by phenols towards the regioselective formation of branched products, which, on reaction with Hoveyda(II) catalyst, lead to cross metathesis, and unsaturated functional compounds. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Saffaj T.,University Sidi Mohammed Ben Abdellah | Saffaj T.,Laboratoire Of Chimie Organique Appliquee | Ihssane B.,Laboratoire Of Chimie Organique Appliquee
Talanta | Year: 2012

The aim of this paper is to apply a new technique for the validation of quantitative analytical procedures based on Bayesian simulation and accuracy profile. Also, an original strategy for estimating measurement uncertainty by the same approach has been developed. The performance of our proposal was confirmed by application to analytical and bio-analytical methods. Compared to the classical strategy, the new approach has a more holistic character. It means that it is no longer necessary to know the various individual steps into which the analytical method can be broken down since this latter is taken as a whole. Furthermore, the Bayesian accuracy profile procedure allows to control the risk associated with the future use of the analytical method. © 2011 Elsevier B.V. All rights reserved.


Saffaj T.,University Sidi Mohammed Ben Abdellah | Saffaj T.,Laboratoire Of Chimie Organique Appliquee | Ihssane B.,Laboratoire Of Chimie Organique Appliquee
Talanta | Year: 2011

This article aims to expose a new global strategy for the validation of analytical methods and the estimation of measurement uncertainty. Our purpose is to allow to researchers in the field of analytical chemistry get access to a powerful tool for the evaluation of quantitative analytical procedures. Indeed, the proposed strategy facilitates analytical validation by providing a decision tool based on the uncertainty profile and the β-content tolerance interval. Equally important, this approach allows a good estimate of measurement uncertainty by using data validation and without recourse to other additional experiments. In the example below, we confirmed the applicability of this new strategy for the validation of a chromatographic bioanalytical method and the good estimate of the measurement uncertainty without referring to any extra effort and additional experiments. A comparative study with the SFSTP approach [1] showed that both strategies have selected the same calibration functions. The holistic character of the measurement uncertainty compared to the total error was influenced by our choice of profile uncertainty. Nevertheless, we think that the adoption of the uncertainty in the validation stage controls the risk of using the analytical method in routine phase. © 2011 Elsevier B.V. All rights reserved.


Saffaj T.,University Sidi Mohammed Ben Abdellah | Saffaj T.,Laboratoire Of Chimie Organique Appliquee | Ihssane B.,Laboratoire Of Chimie Organique Appliquee
Analytica Chimica Acta | Year: 2014

Varlet et al. recently proposed a headspace-gas chromatography-mass spectrometry (HS-GC-MS) method applicable for the routine determination of CO2 in gaseous biologic matrices. This developed bioanalytical method was fully validated according to the SFSTP 1997 guidelines using the accuracy profile as a graphical decision-making tool.In this letter, we discuss the validity of HS-GC-MS method based on the newest SFSTP guideline. In particular, we demonstrate by the estimation of the β-expectation tolerance interval that the error total exceeds the acceptance limits (30%) for the second concentration level (0.5μmolmL-1 vial HS).Furthermore, we show through the risk profile that the probability to have future results inside the ±30% acceptance limits is smaller than 95%. © 2013 Elsevier B.V.


Saffaj T.,University Sidi Mohammed Ben Abdellah | Saffaj T.,Laboratoire Of Chimie Organique Appliquee | Ihssane B.,Laboratoire Of Chimie Organique Appliquee | Jhilal F.,CNRS Laboratory of Engineering and Materials Science | And 3 more authors.
Analyst | Year: 2013

The aim of this paper is to recommend a new strategy for the analytical validation based on the uncertainty profile as a graphical decision-making tool, and to exemplify a novel method to estimate the measurement uncertainty. Indeed, the innovative formula that we offer to assess the uncertainty is based on the calculation of the β-content tolerance interval. Three chemometric methodologies are exposed to build the (β, γ) tolerance interval, namely: the Satterthwaite approximation, the GPQ method (generalized pivotal confidence) and the MLS procedure (modified large simple). Furthermore, we illustrate the applicability and flexibility of the uncertainty profile to assess the fitness of the purpose of chromatographic and electrophoretic analytical methods, which use different instrumental techniques such as liquid chromatography (LC-UV, LC-MS), gas chromatography (GC-FID, GC-MS) and capillary electrophoresis (CE, CE-MS). In addition, we demonstrate here that (β, γ) tolerance intervals will provide perfect estimates of the routine uncertainty. In particular, we show that there is no difference statistically between the uncertainties estimated by our methodology as of the validation stage with those obtained from the routine phase. © 2013 The Royal Society of Chemistry.

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