Volume 7, No. 1 (2006)
Articles
SYNTHESE DE NOUVEAUX DERIVES DE LA BENZIMIDAZO[1,2-c]QUINAZOLINEPP
HARMAOUI R. A.(1), HAJBI Y.(2), AZIANE D.(1), LAZAR S.(3), LEGER JEAN-MICHEL(4), JARRY CHRISTIAN(4), ESSASSI E. M.(4)*, GUILLAUMET GÉRALD(2)
The condensation of 2-(2-aminophenyl)benzimidazoles 2, prepared starting from o-phenylenediamines, with the diethylacetylenedicarboxylate in ethanol afforded a new derivatives of benzimidazo[1,2-c]quinazoline 3 with satisfactory yields. The exact structure of 3a was established by X-ray diffraction.
a-(3,7-DIOXA-r-1-AZABICYCLO[3.3.0]OCT-c-5-YL METHOXY)-DIAZINES (I): SYNTHESIS AND STEREOCHEMISTRY. EXTENTION IN s-TRIAZINE SERIES
BERGHIAN CAMELIA(1)AND(2), PLÉ NELLY(2), TURCK ALAIN(2), DARABANTU MIRCEA1, (2)
The synthesis of the title compounds, consisting in the replacement of chlorine in commercial a-chlorodiazines and cyanuryl chloride by the 3,7-dioxa-r-1-azabicyclo[3.3.0]oct-c-5-ylmethoxy group (Williamson method) is described. The stereochemistry of this new series is analysed in terms of different conformational chirality exhibited in solution (1H DNMR) vs. solid state (X-Ray Diffractometry), meso against chiral forms respectively. In solid state, the inclusion capacity of some chiral networks as well as their supramolecular aggregation is pointed out.
a-(3,7-DIOXA-r-1-AZABICYCLO[3.3.0]OCT-c-5- YLMETHOXY)-DIAZINES (II): FUNCTIONALISATION VIA DIRECTED ORTHO-METALLATION AND CROSS-COUPLING REACTIONS
BERGHIAN CAMELIA(1)AND(2), PLÉ NELLY(2), TURCK ALAIN(2), DARABANTU MIRCEA1, (2)
The functionalisation of the title compounds via regioselective Directed ortho-Metallation (DoM), cross-coupling and the compatibility of the 3,7-DiOxa-r-1-AzaBicyclo[3.3.0]Oct-c-5-ylmethoxy system (DOABO-CH2O) to the reactions typical conditions are preliminarily reported. Its role as Directed ortho-Metallation Group (DoMG) is examined. The chelating ability of some functionalised terms as DOABO-CH2O substituting chiral diarylmethanols and polyaza analogous of 2,6-terpyridine is discussed as intramolecular steric relationships determining configuration and aptitude to bind selectively transition metals respectively.
NOUVELLE VOIES D’ACCES AUX IMIDAZO[1, 2a]PYRIDINES SUBSTITUES EN 3 ET 6 PAR DES ALCENYLES ET (HETERO)ARYLE VIA DES REACTIONS PALLADO-CATALYSEES
KOUBACHI JAMAL(1)(2), EL KAZZOULI SAÏD(1)(2), BERTEINA-RABOIN SABINE(1)*, ABDERRAHIM MOUADDIB(2), GUILLAUMET GÉRALD(1)
Regioselective arylation, heteroarylation and alcenation reactions and Suzuki coupling have been applied and optimized both in classical and microwaves heating for the series of imidazo[1,2-a]pyridines.
NOUVELLE METHODE DE SYNTHESE ET REACTIVITE DE 2,4-DICHLORO ET DE 4-CHLORO PYRIDO[3,2-d]PYRIMIDINES
ABDELLATIF TIKAD(1)AND(2), ROUTIER SYLVAIN(1)*, AKSSIRA MOHAMED(2), LEGER JEAN-MICHEL(3), JARRY CHRISTIAN(3), GUILLAUMET GÉRALD(1)
New mono- and disubstituted pyrido[3,2-d]pyrimidines have been synthetized starting from 2,3-pyridinedicarboxilic anhydride. After obtaining the key intermediate 2,4-dichloropyrido[3,2-d]pyrimidine, many regioselective reactions, showed that dechlorination and SNAr have been realized in position 4. Subsequently, the residual chlorine atom in position 2 has been involved in a series of palladium-catalyzed couplings of Suzuki type.
RECHERCHES DANS LE DOMAINE DES OXADIAZOLES 3,5-DISUBSTITUES
ZARAFU IRINA(1), IVAN LUCIA-VERONICA(1), BADEA IRINEL(2), BACIU ION(1)
Taking into account the practical importance of the 1,2,4- oxadiazoles [1], the paper deals with establishing the optimal synthesis methods of the 3,5-disubstituted derivates containing phenyl, stiryle and para-methoxystiryle radicals. The synthesis method uses as syntons the dithiazolium salts, and the case of 3,5-diphenyle, 3,5-distiryle and 3,5-di(pmetoxystiryle) perchlorates was studied. The compounds purity has been investigated by thin layer chromatography, and the obtained compounds have been analyzed through usual physical and chemical procedures. The antibacterial activity has been studied, concluding that 3,5-distiryle-1,2,4-oxadiazole has a remarkable antimicrobial activity.
ETUDE COMPARATIVE DES METHODES DE SYNTHESE POUR LES SYSTEMES COMPACT CONDENSEES AVEC UN CYCLE THIAZOLO-INDAZOLIQUE
RADULESCU CRISTIANA*, HOSSU ANA-MARIA, MOATER ELENA IRINA, IONIŢĂ IONICĂ
In this paper two compact condensed systems with thiazolic ring, 2-aminothiazolo[4,5-f]indazole and 2-aminothiazolo[5,4-f]indazole, were synthesized. This work presents some synthesis preparative alternatives of these systems, original and unknown in literature, and for each method the reaction conditions are analyzed. Also, the structures of purified heterocyclic systems and of all intermediaries (with a support of TLC and HPLC methods) were studied, for each obtained alternative, by IR spectroscopy, UV spectroscopy, NMR, elemental analysis and melting points. Then, it was realized a comparative study between of the 2- aminothiazolo-indazoles syntheses methods about some aspects (yield, time of reaction, purity of the heterocyclic system, etc.) of reactions and the best preparative way was chosen.
REACTIVTE DES PYRANES - SYNTHESE DE NOUVEAUX HETEROCYCLES POLYNUCLEAIRES CONDENSES: PYRIDINOPYRANES FONCTIONNALISES ET PYRIMIDINOPYRIDINOPYRANES
HAFIDH AFIFA*, GHARBI NEJI
Aminocyanopyranes 1 react respectively with diethylmalonate, acetylacetone and ethylacetoacetate to give the corresponding functional pyranopyridines 2, 3 and 4. The reaction of the compounds 2, 3 and 4 with orthoesters then with primary amines affords respectively the pyranopyridinopyrimidines 5, 7 and 8. Refluxing of the functional pyranopyridines 2 with hydrazine in ethanol leads to the pyrimidinohydrazinopyridinopyranes 6. The structures of all prepared products were determined on the basis of their IR, 1H and 13C NMR spectra.
SYNTHESIS, CHARACTERIZATION AND BIOLOGIC ACTIVITY OF NEW COMPLEXES OF 3,6 DIAMINOACRIDINE (PROFLAVINE) WITH 3d AND 4f METALS
RUS ADINA(1), NEGREANU-PIRJOL TICUTA(2), GIURGINCA MARIA(1), GURAN CORNELIA(1)
In this paper we report the preparation, characterization and antibacterial activity of some new complex compounds of 3,6- diaminoacridine (L) with 3d - Fe(III) and Cu(II) and 4f - Gd(III) and Ce(III) metals. On the basis of chemiluminescence properties studies of complex compounds antioxidative character of these complex compounds is discussed.
FORMATION DE BLOCS POUR LES REACTIONS DE WITTIG
SAUCA SORIN-NICOLAE(1), IRIMIA MARINELA(2)
In this paper, the synthesis of each necessary components for the Wittig coupling reaction, aldehydes and phosphonium salts, is presented. In the last years the Wittig reactions began to have a crucial role in the field of retinoids’ chemistry. The diversity of possible reactants brought a specific interest on these compounds. Obtaining of the anhydride by using a protective group TBDPSiCl and the 4-oxo-ß-ionone through the oxidation of the ß-ionone with PCC is presented. The tert-BDPSi group offers a unique and novel device that represents a significant improvement concerning the existing groups: the primary alcohol groups are preferentially transformed into secondary siloxane groups. This group has unique stability properties compared with other protective groups, being not affected by the hydrogenolysis conditions, unlike siliconed ethers, sensitive to hydrogenolysis. The DMSO was activated by oxalyl chloride (Swern oxidation) at about - 60°C, by loosing CO2 and CO in order to form a sulfonium chloride salt. The resulting agent is better than the DMSO- anhydrous trifluoroacetic acid. The following analyzing techniques have been used: plates and column chromatographical separation, melting point measurement, RMN, IR and mass spectroscopy.
ZEOLITHE Al-MCM-22: ETUDE DE L’ACIDITE PAR IR-TF, XPS ET MICROCALORIMETRIE
FECHETE IOANA(1)AND(2)*, CAULLET PHILIPPE(2), DUMITRIU EMIL(1), HULEA VASILE(3), GUIMON CLAUDE(4), KESSLER HENRI(2)
MCM-22 (IZA code MWW) zeolite with Si/Al of 15 and 34 was characterized by N2 adsorption isotherm, 27Al and 29Si MAS RMN spectroscopy, infrared spectroscopy (FTIR), X - ray photoelectron spectroscopy (XPS) and microcalorimetry. The as-synthesized samples gives a signal from four-coordinated framework Al, and the calcined samples gives two signals, from four-coordinated framework Al and from six-coordinated extra-framework Al (EFAl). In the 29Si NMR spectra showed five at seven different signals. XPS spectra of N1s binding energies showed two types of sites: Brönsted and Lewis. Pyridine adsorbed on Brönsted and Lewis sites appeared at 1545 cm-1 and 1455 cm-1, respectively (FTIR). Both samples of MCM-22, show a relatively high proportion of strong Brönsted sites. The observed Lewis acidity can be related with extraframework Al species, indicating that some dealumination took place during the calcination step. Microcalorimetry experiments indicate the presence of three type of acid sites.
CARACTERISATION PHYSICO-CHIMIQUE DE LA ZEOLITHE Fe-MCM-22
FECHETE IOANA(1)AND(2)*, DUMITRIU EMIL(1), CAULLET PHILIPPE(2), HULEA VASILE(3), GUIMON CLAUDE(4), KESSLER HENRI(2)
Ferrisilicate molecular sieve with the MCM-22 structure, has been carried out by different methods, using HMI as a source of organic template, different silica and iron sources. Fe-MCM-22 zeolite has been synthesized as a unique phase for Si/Fe=16. The trivalent elements isomorphous substitution was demonstrated by X-ray powder diffraction, BET, H2 temperature programmed reduction (TPR), infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS). A comparison of Si/Fe ratios determined by chemical analysis and XPS method were studied. Calcination leads to complete removal of the template. During this process a significant fraction of iron is dislodged to extraframework positions. H2TPR indicates that the presence of different forms of iron. XPS spectra of N1s binding energies showed two types of sites: Brönsted and Lewis.
BISTRIAZENE POLYURETHANES: SYNTHESIS, CHARACTERIZATION AND PHOTOBEHAVIOR
BURUIANĂ EMIL(1)*, MELINTE VIOLETA(1), BURUIANA TINCA(1), SIMIONESCU BOGDAN(1), LIPPERT THOMAS(2)
Two new bistriazene diols, 1,1’[4,4’-diphenyl]-3,3’-di(ß-hydroxyethyl methyl)-bistriazene (TDF) and 1,1’[4,4’-diphenylsulphone]-3,3’-di(ß-hydroxyethyl methyl)-bistriazene (TSO) were synthesized via an electrophilic N-N coupling between a quaternary ammonium salt and Nmethyl-monoethanol amine. These monomers were used as co-partners in polyaddition with 2,4-tolylene diisocyanate (2,4- and 2,6-TDI isomer mixture, 80:20 v/v) or 4,4’ methylene diisocyanate, respectively, in order to obtain new hard type polyurethanes. The photosensitivity of monomers and polymers was evaluated by UV irradiation, in methanol or DMF solution and as thin films following the disappearance of the p-p* absorption band from the UV spectra corresponding to the triazene chromophore. As a novel trend, the bistriazene polyurethanes were structured by laser irradiation (? = 308 nm) in order to evaluate their ability to deliver efficient materials in microlithography.
FLUORESCENT POLYMERS FOR SENSOR APPLICATIONS
BURUIANĂ EMIL(1)AND*, BURUIANA TINCA(1), OLARU MIHAELA(1), ZAMFIR MIRELA(1), POHOAŢĂ VALENTIN(2)
Two soft polyetherurethanes with pyrene or anthracene fluorofore on the quaternary ammonium groups were synthesized and characterized. The properties of these polymers and the corresponding monomers were studied through fluorescence spectroscopy, and for the pyrene-polymer the quenching of fluorescence in film state by nitrobenzene used as efficient quencher was also performed. The fluorescence measurements suggested a hydrophilic environment for pyrene molecule in the polycation, where an increased excimer emission was evidenced. UV photolysis experiments performed with light of 365 nm on one synthesized model containing anthracene in DMF solution showed that the absorption maximum from 367 nm decreased gradually with irradiation time, as the [4+4] dimerization process of anthracene occurred. Since the above polymers can form flexible of elastomeric type, it should be possible to develop vapor-based chemical sensors for detection of some analytics.
MAGNETIC SUPPORT NANOPARTICLES FOR THE TARGETING OF DRUGS: PHYSICAL CHARACTERIZATION AND MANIPULATION IN MAGNETIC FIELD
UDREA LAURA ELENA(1)AND(2), ROTARIU OVIDIU(2), POPA MARCEL(1)
The magnetic capture of colloidal magnetic particles (MPs) flowing in capillary tubes is studied. This models magnetic the embolization of “blood vessels” as a treatment for cancer. The study investigates the evolution of MPs deposition using video imaging and flow recording techniques. The parameters of practical importance (length of MPs deposits, time of capillary blocking) are estimated, and they are dependent on the initial fluid velocity, the MPs concentration and the position of capillary tubes within the magnetically active zone. The study reveals that stable deposits of colloidal MPs block - up the capillary tubes on lengths of few centimeters when the tubes are positioned in the proximity of the magnetic poles and the colloid velocity is low (< 0.5 cm/s). Depending on the particle concentration and the flow velocity, the blocking time varies between 10 to 30 minutes. A dynamic deposition regime appears when the capillary tubes are positioned far away (1.5 to 6.0 cm) from the magnetic poles. In this case the length of the MPs deposits increases up to 7.7 cm, but the deposits are unstable and avalanches take place. These results indicate that magnetic embolization is suitable for treating sub-surface cancers within the human body.
THE ROLE OF THE ORGANIC SOLVENT IN OBTAINING HYDROTALCITE - LIKE ANIONIC CLAY NANOPOWDERS WITH SPECIFIC TEXTURAL AND POROUS PROPERTIES
CARJA GABRIELA(1)*, CIOBANU GABRIELA(1), MASAYUKI TOYOTA(2)
Hydrotalcite - like anionic clays were synthesized by the sol-gel method while ethanol and phenol were used as organic solvents in the synthesis medium. The X-ray diffraction analysis points out that the obtained nanopowders possess a well crystallized hydrotalcite – like anionic clay structure. The N2 adsorption analysis reveals that the features of the nanoparticles ensemble pattern and the textural properties of the mesoporous structure are dependent on the nature of the organic solvent. When ethanol is used in the synthesis medium the emerged nanoclay present a relatively uniform porous structure with a specific surface area of 140 m2/g and the value of N2 adsorption volume is equal to 270 mL/g. On the contrary when phenol is present as major organic solvent in the synthesis medium a lower specific surface area is obtained (77 m2/g) while the value decreases to 170 mL/g. These results point out that the nature of the organic solvent is important for tailoring the textural and porous properties of hydrotalcite – like anionic clay nanostructures.
POLYORGANOPHOSPHAZENES – MATERIAUX INORGANIQUES NOUVEAUX AUX MULTIPLES APPLICATIONS
STAN MATEESCU RALUCA(1)*, MÂNZU DENISA(1), VIEZURE IOANA(2), MOCIOI MIHAELA(1), GURAN CORNELIA(1)
In this paper we report the results regarding the synthesis of two polyphosphazenes derivatives, from phosphazene having as side groups: o-tolylbiguanide and 4,4 - diamino 2,2 - stilbene disulfonate acid. These new polymers were characterised by NMR, FT-IR. In interaction with d metals they form coordinative species and on this base they can be used for removal of d metal ions (Cu2+, Cr3+; Mn2+, Fe2+; Co2+, Ni2+) from wastewaters.
LA DIMERISATION DE L’ETHYLENE EN PRESENCE DES COMPLEXES MII (2,2’-BIPYRIDINE) (MII = Fe, Co) SUPPORTES SUR ZEOLITHE Y
ZĂVOIANU RODICA(1), BÎRJEGA RUXANDRA(2), PAVEL OCTAVIAN DUMITRU(1), CRUCEANU ANCA(1), ANGELESCU EMILIAN(1)
The work presents the preparation and characterization of Fe and Co complexes with 2,2’bipyridine (2,2’-bpy) ligands supported on Y zeolite as well as their catalytic activity for ethylene dimerisation. The catalysts were characterized by using XRD, FTIR, DR-UV-Vis spectroscopy and TG-DTA analysis. It was found that Co(2,2’-bpy)2Cl2 supported on Y zeolite has an exceptional good selectivity (>95%) to the formation of 1-butene.
DOMAINES DES APPLICATIONS DES MATÉRIAUX PHOTOCHROMIQUES
IONIŢĂ IONICĂ(1)*, ALBU ANA-MARIA(2), RADULESCU CRISTIANA(1), HOSSU ANA-MARIA(1), MOATER ELENA IRINA(1)
The researches developed in the last years in optics field, underline those most interesting materials for storing and processing data, the photochromic polymers. In this way, the azoic polymers show a peculiar applicative interest. When the azobenzene group is incorporated into polymeric matrix, conformational modification plays a fundamental role in the recording and preserved process.
CARACTERISATION DE CERTAINS PRINCIPES ACTIFS DE ULVA LACTUCA ET ULVA RIGIDA – ALGUES VERTES DU LITTORAL ROUMAIN DE LA MERE NOIRE
SÎRBU RODICA*, SAVA CONSTANŢA, GHERGIC DOINA LUCIA, MOUIMA NADINE PASSY
Among algae, green algae contribute to the creation of a biological balance in seas and oceans, taking part to the water purification processes, carbon fixation and serving as feed for marine fauna. For mankind, they are important in food production, in medical fields, dietetics and cosmetics. Ulva Lactuca and Ulva Rigida are the most important green algae from the mean coastal area of the Black Sea. Their industrial capitalization is still poor; no theoretical studies have yet been performed. In this approach, the present work outlines in a detailed manner the active principles of these algae that, due to the recent established ecological equilibrium, represent nowadays a plentiful biomass.
ETUDES ELECTROCHIMIQUES SUR LES DERIVES DE NITROCYCLOPROPANE
CRISTEA CECILIA(1)*, LESSARD JEAN(2), JITARU MARIA(3)
The article present the studies made on several aliphatic nitro derivatives. The studies were made in acetonitrile. For all the investigated compounds we observed the cleavage in cyclopropyl radical and nitrite ion in an aprotic medium. Cyclic voltammograms and preparative electrolyses (performed under potentiostatic conditions in an H cell on a glassy carbon in dry acetonitrile containing Bu4NPF6, c = 0.1 M, as supporting electrolyte) of nitrocumene and of some nitrocyclopropanes will be presented and discussed in the light of the different mechanistic pathways of cleavage of the radical anions.
COMPORTEMENT ELECTROCHIMIQUE ET ANTIBACTERIENNE DES DERIVES DE (1S, 2S)-2- AMINO-1-(4-NITROPHENYLE)- PROPANE-1,3-DIOL
CRISTEA CECILIA(1)*, VOICULESCU G.(2), JITARU MARIA(2), MOINET C.(3)
Derivatives of (1S, 2S)-2-amino-1-(4-nitrophenyl)- propane-1,3-diol were studied because of their potential biological activity. Using the electrogenerated intermediates (hydroxylamine and nitroso derivatives) N-sulphonylphenylhydroxylamines and benzoxazine diones were obtained with good yields. Their antibacterial activity was investigated on several gram-negative and gram-positive bacilli by two techniques: broth-dilution method and agar-dilution method.
DÉGRADATION ÉLECTROCHIMIQUE DE LA LIAISON –N=N–: ÉTUDE DES PARAMÈTRES SUR UNE MOLÉCULE MODÈLE, METHYLORANGE
JITARU MARIA*, STAN MARIAN, HURDUCAS MIHAELA
The main purpose of this paper is the electrochemical oxidation of azo linkage –N=N– and to obtain some data regarding the electrochemical behavior of Methyl Orange on different electrodes and conditions (pH, electrolytes, concentrations). Different electrode materials, like CV (glassy carbon), Hg and BDD (boron doped diamond) were used to investigate the electrochemical behavior of the mono-azo dye, especially of a model molecule methyl orange, but also for other substituted azo dyes. The results obtained from the voltamograms are useful to establish the influence of the factors mentioned earlier, on the discoloration yield.
METHODES SPECTROPHOTOMETRIQUES ET CHROMATOGRAPHIQUES POUR LA DETERMINATION DE LA VITAMINE C
HOSSU ANA-MARIA*, RADULESCU CRISTIANA, IONIŢĂ IONICĂ, MOATER ELENA IRINA
Vitamin C is an important biological molecule involved in many biological and biochemical processes as reducing agent, enzyme cofactor and nutritional factor. Due to the widespread use of vitamin C, a large number of methods have been developed for quantifying vitamin C contents in natural and fortified food samples and pharmaceuticals: titrimetry, voltammetry, potentiometry, fluorometry, spectrophotometry, kinetic-based chemiluminescence, flow injection analyses (FIA) and chromatography. It is therefore essential to assess these methods. Accordingly, this paper reviews spectrophotometric and chromatographic methods for the determination of vitamin C from food samples and pharmaceutical products.
DETERMINATIONS CHROMATOGRAPHIQUES, SPECTROPHOTOMETRIQUES ET TITRIMETRIQUES DE VITAMINE C DANS PHARMACEUTIQUES
HOSSU ANA-MARIA(1)*, SCRIPCARIU MIHAELA(2), RADULESCU CRISTIANA(1), MOATER ELENA IRINA(1), IONIŢĂ IONICĂ(1)
The determination of vitamin C has gained increased significance in several areas of analytical chemistry such as pharmaceutical, clinical and food application. In this paper, three rapid and accurate methods of determining ascorbic acid are presented. The proposed methods were successfully applied to pharmaceutical preparations. Potassium iodide has been used as the titrant for the determination of acid ascorbic, according to pharmacopoeias. The present paper reports on a direct spectrophotometric method of determining ascorbic acid with chloric acid 0.1 N by measuring the absorbance of the reaction at 245 nm. HPLC analyses of ascorbic acid on column Lichrosorb NH2 with acetonitril-KH2PO4 as the mobile phase were compared with the titrimetric and spectrophotometric methods.
OPTIMISATION EN SYNTHESE PARALLELE SUR PHASE SOLIDE DE QUINAZOLINEDIONES INHIBITRICES DE S-FARNESYLTRANSFERASE
KUCHARCZYK NATHALIE(2), TIZOT ANDRÉ(1), MERER GOULVEN(2), DHAINAUT ALAIN(2), TUCKER C. GORDON(2), FAUCHÈRE JEAN-LUC(1), GOLDSTEIN SOLO(1)
The discovery of anti-cancer drugs based on the post traductional modification of Ras protein has been thoroughly studied in the last years. The aim of the present study is to optimize the solid phase synthesis of quinazolinediones, compounds that present an inhibitory activity of the S-farnesyltransferaze (FTase). Two strategies for obtaining a new FTase inhibitor, S35028, are presented.
SYNTHESE ET PROFIL PHARMACOLOGIQUE DE NOUVEAUX LIGANDS NICOTINIQUES
CHARTON YVES(1), GUILLONNEAU CLAUDE(1), LOCKHART BRIAN(2), LESTAGE PIERRE(2), GOLDSTEIN SOLO(1)
Different studies proofed that nicotine is able to improve cognition performances, both to humans and animals [1]. In a previous study [6] we have demonstrated that S35836-1, a carbamate analogue of acetylcholine, is a specific ligand of nicotinic neural receptors of acetylcholine (nAChRs), with influence in Alzheimer and Parkinson diseases. The present paper presents new synthesis schemes of receptors with restricted conformational mobility.