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USE OF WOOD DERIVATIVES AS DOPING / DISPERSING AGENTS IN THE PREPARATION OF POLYPYRROLE AQUEOUS DISPERSIONS  [PDF]
Claudia Sasso,Mathieu Fenoll,Olivier Stephan,Davide Beneventi
BioResources , 2008,
Abstract: Polystyrene sulfonic acid (PSS), lignosulfonic acid (LS) sodium salts, and carboxymethylcellulose (CMC) were used as doping/dispersing agents in the chemical polymerization of polypyrrole (Ppy). Conductivity measure-ments performed on dry Ppy pellets showed a sharp increase in conductivity when adding the anionic polymers to the polymerization liquor. For a polyanion/pyrrole weight ratio ranging between 0.1 and 0.6, the highest conductivity was given by PpyCMC (82 S/m) and PpyPSS (80 S/m), followed by PpyLS (6 S/m). On the other hand, for a polyanion/pyrrole ratio higher than 0.6, the conductivity of PpyPSS systems sharply decreased, and for polyanion/pyrrole ratios higher than 1, the highest conductivity was given by PpyCMC (~10 S/m), followed by PpyLS (~7 S/m) and PpyPSS (~5 S/m). Zeta-potential measurements showed that the surface charge of Ppy was strongly affected by the polyanion type and amount. Cationic Ppy particles were obtained in the presence of the two polymers bearing strongly acidic moieties (PSS and LS). Anionic PpyPSS colloids were obtained at the highest PSS/Py ratio, after the degradation of the conducting properties. When using a weakly acidic dopant (CMC), PpyCMC colloids had a negative charge for all of the tested conditions.
New Multi-1,2,3-Selenadiazole Aromatic Derivatives  [PDF]
M. Al-Smadi,S. Ratrout
Molecules , 2005, DOI: 10.3390/10091126
Abstract: The aromatic polyketones 3a-d are versatile compounds for the synthesis of the multi-1,2,3-selenadiazole aromatic derivatives 1a-d. The preparation starts with the reaction between the multi-bromomethylene benzene derivatives 2a-d and 4-hydroxy- acetophenone to give compounds 3a-d which are transformed through the reaction with semicarbazide hydrochloride or ethyl hydrazine carboxylate into the corresponding semicarbazones derivatives 4a-d or hydrazones 5a-d. The reaction with selenium dioxide leads to regiospecific ring closure of semicarbazones or hydrazones to give the multi- 1,2,3-selenadiazole aromatic derivatives in high yield.
SYNTHESIS OF SOME SECONDARY AMINE DERIVATIVES BEARING A HETEROARYL FRAGMENT
KOUZNETSOV,VLADIMIR V; ASTUDILLOSAAVEDRA,LUIS; VARGAS MéNDEZ,LEONOR Y.; CAZAR RAMíREZ,MARíA E;
Journal of the Chilean Chemical Society , 2004, DOI: 10.4067/S0717-97072004000400010
Abstract: diverse n-(heteroarylmethyl)anilines were easily prepared from corresponding aldimines derived from commercially available aromatic aldehydes and anilines. new series of substituted nh-tetrahydroquinolines were also prepared using imino-diels-alder reaction between aldimines and n-vinylpyrrolidin-2-one in the presence of bf3.oet2 and the multi-component condensation reactions using a friendly ecological catalyst (bicl3). the secondary amines obtained bearing a heteroaryl moiety were tested as possible antibacterial and antifungal agents
SYNTHESIS OF SOME SECONDARY AMINE DERIVATIVES BEARING A HETEROARYL FRAGMENT  [cached]
VLADIMIR V KOUZNETSOV,LUIS ASTUDILLOSAAVEDRA,LEONOR Y. VARGAS MéNDEZ,MARíA E CAZAR RAMíREZ
Journal of the Chilean Chemical Society , 2004,
Abstract: Diverse N-(heteroarylmethyl)anilines were easily prepared from corresponding aldimines derived from commercially available aromatic aldehydes and anilines. New series of substituted NH-tetrahydroquinolines were also prepared using imino-Diels-Alder reaction between aldimines and N-vinylpyrrolidin-2-one in the presence of BF3.OEt2 and the multi-component condensation reactions using a friendly ecological catalyst (BiCl3). The secondary amines obtained bearing a heteroaryl moiety were tested as possible antibacterial and antifungal agents
Synthesis and biological activity of some triazole-bearing benzimidazole derivatives  [PDF]
K. F. ANSAR,C. LAL,R. K. KHITOLIYA
Journal of the Serbian Chemical Society , 2011,
Abstract: A number of N’-(arylmethylidene)-2-(2-methyl-1H-benzimidazol-1-yl)acetohydrazide and 4-aryl-5-[(2-methyl-1H-benzimidazol-1-yl)methyl]-4H-1,2,4-triazole-3-thiol derivatives were synthesized by incorporating various aromatic and heterocyclic substituents on 2-methyl-1H-benzimidazole. The structures of all the synthesized compounds were elucidated based on their elemental analyses and spectral data. The in vitro activities of these compounds against bacteria and fungi were evaluated by the disc diffusion and the minimum inhibitory concentration (MIC) methods. Some of the synthesized derivatives were found to be as active as kanamycin (standard drug).
Clean-up of extracts for nitrated derivatives of polycyclic aromatic hydrocarbons analyses prior to their gas chromatography determination
Prycek, Jirí;Ciganek, Miroslav;Simek, Zdenek;
Journal of the Brazilian Chemical Society , 2007, DOI: 10.1590/S0103-50532007000600004
Abstract: this study was focused on the fractionation of the mixture of polycyclic aromatic hydrocarbons and their derivatives, especially nitrated derivatives, found in soil and roadside dust extracts. liquid chromatography with an open silica gel bed was used. different volumes of hexane, hexane:dichloromethane (1:1 and 4:1, v/v), dichloromethane and methanol were used for the elution of individual fractions. increasing volume of hexane was not sufficient for complete separation of a slightly polar fraction from the aromatic fraction. increasing content of hexane in the elution mixture improved the separation of the group of target compounds. soil and roadside dust extracts were obtained by using a pressurised solvent extractor with dichloromethane as the extraction solvent. detection limits of the method ranged from 50 to 220 pg of individual nitro-pahs injected into gas chromatograph. a significant amount of 1-nitropyrene was detected in the real samples collected close to the brno centre.
Dynamic Behavior of Polycyclic Aromatic Hydrocarbons and Their Derivatives after Oils Spill in Water  [PDF]
Pranudda Pimsee, Caroline Sablayrolles, Mireille Montréjaud-Vignoles, Julien Guyomarch, Nicolas Lesage, Pascale de Caro
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.58069
Abstract:

Within the framework of Migr’Hycar research project, the fate of oil spill was studied with the aim to characterize their physical-chemical behaviour. For this purpose, seven petroleum oils commercially available were tested and the distributions of the water soluble components were determined according to two experimental devices; laboratory conditions and pilot conditions in Polludrome. In the dissolved fraction, 41 polycyclic aromatic hydrocarbons and their derivates were quantified, among them are 16 EPA priority pollutants. A coupling of the stir bar sorptive extraction method and high performance gas chromatography mass spectrometry were used. Analyses showed that naphthalenes series constitute the major part of the water soluble fraction from fresh oils. In fact, light and heavy molecules have different contributions to solubilization kinetics. From the results, a linear correlation was established between the density of oils and the times of maximum solubilization. Moreover, the effect of 10% ethanol in gasoline was observed on the profile of solubilized PAHs in water. Kinetic patterns obtained with Polludrome showed the influence of surface water/oil ratio (WOR) on the volatilization process. Compared to laboratory conditions, the dynamic conditions of Polludrome led to an enhanced evaporation process, thus shifting the solubility peak.

New Lipophilic Piceatannol Derivatives Exhibiting Antioxidant Activity Prepared by Aromatic Hydroxylation with 2-Iodoxybenzoic Acid (IBX)  [PDF]
Roberta Bernini,Maurizio Barontini,Carmela Spatafora
Molecules , 2009, DOI: 10.3390/molecules14114669
Abstract: Piceatannol (E-3,5,3’,4’-tetrahydroxystilbene) is a phytoalexin synthesized in grapes in response to stress conditions. It exhibits strong antioxidant and antileukaemic activities due to the presence of the catechol moiety. To modify some physical properties like solubility, and miscibility in non-aqueous media some new previously unreported piceatannol derivatives having lipophilic chains on the A-ring were prepared in good yields by a simple and efficient procedure. The key step was a chemo- and regioselective aromatic hydroxylation with 2-iodoxybenzoic acid (IBX). The new compounds showed antioxidant activity and seemed promising for possible applications as multifunctional emulsifiers in food, cosmetic and pharmaceutical fields.
Synthesis and Reactions of Some New Diiodocoumarin Derivatives Bearing Side Chains and Some of Their Biological Activities
American Journal of Chemistry , 2011, DOI: 10.5923/j.chemistry.20110101.01
Abstract: The synthesis of 6,8-diiodocoumarin derivatives (2-6) by condensation of 3,5-diiodosalicylaldehyde (1) with active methylene compounds is described. Reaction of 6 with malononitrile afforded two products pyridine and ethylidine malononitrile derivatives (7, 8), while treatment of 6 with p-methoxybenzylidenemalononitrile in absolute ethanol/piperdine provided pyrane and bis coumarin derivatives (9,10). Reaction of 6 with DMF/POCl3 afforded three products coumarin derivatives (11,12,13), while bromination of 6 with Br2/AcOH gave 3-bromo-6,8-diiodocoumarin (14). Treatment 6 with aromatic aldehydes gave the corresponding 3-(3-arylacryloyl)-6,8-diiodocoumarin derivatives (16a,b) while reaction of 6 with aniline or phenylhydrazine gave coumarin derivatives 17 and 18. Reaction of 18 with DMF/POCl3 gave pyrazole-4-aldehyde derivative (19). Condensation of 19 with active methylene compounds afforded pyrazole and pyrimidine derivatives (20a-c) and 21). Reaction of 8 with sulphur via the Gewald reaction afforded thiophene derivative (22), while the reaction of 8 with p-methoxybenzylidenemalononitrile gave biphenyl derivative (23). Treatment of 8 with chloroacetyl chloride afforded the furan derivative (24). The structures of the newly synthesized compounds were confirmed by IR, 1H NMR and 13C NMR and mass spectral data. The newly synthesized compounds were also screened for their antimicrobial activity.
Synthesis, supramolecular structures and luminescent properties of quinacridone derivatives bearing carbazole groups
GuoLi Zhao,Yan Fan,Cheng Huo,Hang Bian,WeiFeng Song,JingYing Zhang,Yue Wang
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0062-1
Abstract: The syntheses of three carbazyl-containing quinacridone derivatives, N,N′-di((N-carbazyl)-n-butyl) quinacridone (DCBQA), N,N′-di((N-carbazyl)-n-hexyl)quinacridone (DCHQA) and N,N′-di((N-carbazyl)-n-octyl)quinacridone (DCOQA), are reported, and the photoluminescent (PL) characteristics are presented. The single crystal X-ray structures of DCBQA, DCHQA and DCOQA are investigated. The crystal of DCBQA is characterized by intermolecular п п interactions between quinacridone cores and carbazole moieties resulting in the formation of DCBQA molecule layer, in which every quinacridone core is surrounded by four carbazole groups. In DCHQA crystal, molecules assemble into two kinds of oriented columns based on intermolecular п п interactions between quinacridone cores. The DCOQA crystal displays intermolecular CH п and hydrogen bonding interactions feature. In DCOQA solid, every quinacridone core is sandwiched by two alkyl chains from two adjacent DCOQA molecules and simultaneously linked together with two other quinacridone cores by hydrogen bonding interactions. The PL spectra of the three compounds in solution exhibit concentration-dependent properties and their PL quantum causes decrease with the increasing concentration.
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