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Full-Text Articles in Chemistry

Synthesis, Structural Characterization, And Antimicrobial Efficiency Of Sulfadiazine Azo-Azomethine Dyes And Their Bi-Homonuclear Uranyl Complexes For Chemotherapeutic Use, Abdalla M. Khedr, Fawaz A. Saad Jan 2015

Synthesis, Structural Characterization, And Antimicrobial Efficiency Of Sulfadiazine Azo-Azomethine Dyes And Their Bi-Homonuclear Uranyl Complexes For Chemotherapeutic Use, Abdalla M. Khedr, Fawaz A. Saad

Turkish Journal of Chemistry

Two sulfadiazine azo-azomethine dyes containing two active coordination centers and their bi-homonuclear UO_2(II)-complexes were synthesized for potential chemotherapeutic use. The ligands were prepared, starting from the coupling of sulfadiazine dizonium salt with acetylacetone, followed by condensation with ethylenediamine and 1,6-hexanediamine (HL^I and HL^{II}) using a modified literature procedure. The structures of the ligands and their UO_2(II)-complexes were elucidated by conventional and thermal gravimetric analyses, molar conductivity, magnetic susceptibility, and IR, UV-Vis, ^1H NMR, and mass spectra. The analytical and spectral data supported the binuclear formulation of the complexes with a 2:1 metal to ligand ratio and octahedral geometry. The molar …


Pfam Catalyzed Enantioselective Diethylzinc Addition To Imines, Özdemi̇r Doğan, Eda Çağli Jan 2015

Pfam Catalyzed Enantioselective Diethylzinc Addition To Imines, Özdemi̇r Doğan, Eda Çağli

Turkish Journal of Chemistry

Chiral amines are important starting materials for the synthesis of biologically important compounds. Enantioselective addition of dialkylzinc reagents to imines is a reliable method for the synthesis of these compounds. Different chiral catalysts were developed and used for this method. Phosphorous based PFAM catalysts were tried for the first time in the enantioselective synthesis of amines by reacting diethylzinc with N-sulfonyl imines and N-diphenylphosphinoyl imines. Chiral amines were isolated with moderate to acceptable yields and enantioselectivities.


Improvement Of Solubility Of Celecoxib By Inclusion In Mcm-41 Mesoporous Silica: Drug Loading And Release, Şahi̇ka Günaydin, Ayşen Yilmaz Jan 2015

Improvement Of Solubility Of Celecoxib By Inclusion In Mcm-41 Mesoporous Silica: Drug Loading And Release, Şahi̇ka Günaydin, Ayşen Yilmaz

Turkish Journal of Chemistry

Celecoxib is a poorly water-soluble nonsteroidal anti-inflammatory drug. Here we report four ordered mesoporous silica MCM-41 supports with different particle size, pore volume, and surface properties to investigate their loading capacity with celecoxib and their release abilities. Spherical MCM-41 mesoporous supports less than 50 nm in diameter were prepared and to compare the effect of the template removal process on morphology of samples, acid extraction and calcination methods were used. Moreover, nearly 500 nm sized rod-shaped MCM-41 mesoporous silica was obtained by changing the template concentration in preparation. Boron doping was performed to determine the effect of a heteroatom on …


Synthesis And Electrochemistry Of Phthalocyanines Bearing [(3,4-Dimethoxybenzyl)Oxy] Groups, İpek Ömeroğlu, Zekeri̇ya Biyiklioğlu Jan 2015

Synthesis And Electrochemistry Of Phthalocyanines Bearing [(3,4-Dimethoxybenzyl)Oxy] Groups, İpek Ömeroğlu, Zekeri̇ya Biyiklioğlu

Turkish Journal of Chemistry

In this study peripherally tetra-substituted metal-free, metallophthalocyanines bearing (3,4-dimethoxybenzyl) oxy groups have been synthesized and characterized. Electrochemical properties of novel phthalocyanines 4, 5, 6, and 7 were determined by cyclic and square wave voltammetry in order to define their possible applications in different electrochemical technologies. Co^{II} and Ti^{IV}O metal ions behave as redox active cations in the core of the CoPc and TiOPc complexes, respectively. Voltammetric studies revealed that phthalocyanines have reversible/irreversible redox processes, which are the main requirement for the technological usage of these compounds.


Hplc Fluorescence Determination Of Ochratoxin A Utilizing A Double Internal Standard And Its Application To Poultry Feed, Muzaffer Tunçel, Eli̇f Mi̇ne Öncü Kaya, Ülkü Di̇lek Uysal, Tufan Güray Jan 2015

Hplc Fluorescence Determination Of Ochratoxin A Utilizing A Double Internal Standard And Its Application To Poultry Feed, Muzaffer Tunçel, Eli̇f Mi̇ne Öncü Kaya, Ülkü Di̇lek Uysal, Tufan Güray

Turkish Journal of Chemistry

A validated liquid chromatography method employing a fluorescence detector for the determination of ochratoxin A (OTA) was developed with double internal standard and it was applied to ten different poultry feeds. The analysis was performed in an octadecyl silane column using a solvent system [ACN:water:formic acid (50:50:1.25, v/v/v)] by isocratic elution. The flow rate and injection volume were 1 mL min^{-1} and 12 \mu L, respectively. Signals were detected at 278(\lambda_{ex})/315(\lambda_{em}) and 330(\lambda_{ex})/450(\lambda_{em}) nm between 0 and 8, and 8.01 and 20.0 min, respectively. The method was validated with precision, linearity, accuracy, limit of detection, limit of quantification, robustness, and …


Kinetics Study And Influence Of Water-Soluble Polymer On The Electrodeposition Of Iron From A Citrate-Chloride Electrolyte On The Basis Of Fe(Iii), Vyacheslav Protsenko, Felix Danilov Jan 2015

Kinetics Study And Influence Of Water-Soluble Polymer On The Electrodeposition Of Iron From A Citrate-Chloride Electrolyte On The Basis Of Fe(Iii), Vyacheslav Protsenko, Felix Danilov

Turkish Journal of Chemistry

The kinetics of the iron electrodeposition reaction from a plating bath containing trivalent iron ions is investigated in the present work. The electrochemical reaction is stated to proceed via the formation of relatively stable intermediates: Fe(II) ions. Only a part of the total amount of Fe(II) ions formed at the first stage of Fe(III) discharge is reduced further, producing metal iron. The effect of polyhexamethyleneguanidine hydrochloride (with an average molecular weight of 1000) on the iron deposition is ascertained. The presence of polymer additive in the iron electrolyte appreciably affects the rate of iron deposition, while the polymer additive does …


Characterization Of A Cu$^{2+}$-Selective Fluorescent Probe Derived From Rhodamine B With 1,2,4-Triazole As Subunit And Its Application In Cell Imaging, Na Li, Chunwei Yu, Yuxiang Ji, Jun Zhang Jan 2015

Characterization Of A Cu$^{2+}$-Selective Fluorescent Probe Derived From Rhodamine B With 1,2,4-Triazole As Subunit And Its Application In Cell Imaging, Na Li, Chunwei Yu, Yuxiang Ji, Jun Zhang

Turkish Journal of Chemistry

A rhodamine B derivative containing 1,2,4-triazole as subunit was characterized as an "off-on" type Cu$^{2+}$-selective fluorescent probe. It exhibited high selectivity and sensitivity for Cu$^{2+}$ in ethanol-water solution (9:1, v:v, pH 7.0, 20 mM HEPES) and underwent ring opening. A prominent fluorescence enhancement at 570 nm was observed in the presence of Cu$^{2+}$ with the change in the absorption spectrum, and a 1:1 metal-ligand complex was formed. With the optimized experimental conditions, the probe exhibited a dynamic response range for Cu$^{2+}$ from 8.0 $\times $ 10$^{-7}$ to 7.5 $\times $ 10$^{-6}$ M with a detection limit of 2.3 $\times $ …


Acid-Free Synthesis Of S-Nitrosothiols At Neutral Ph By Shock-Freezing In Liquid Nitrogen, Dimitrios Tsikas, Anke Böhmer, Arne Trettin, Arslan Arinç Kayaçelebi̇ Jan 2015

Acid-Free Synthesis Of S-Nitrosothiols At Neutral Ph By Shock-Freezing In Liquid Nitrogen, Dimitrios Tsikas, Anke Böhmer, Arne Trettin, Arslan Arinç Kayaçelebi̇

Turkish Journal of Chemistry

A laboratory method for the acid-free synthesis of S-nitrosothiols (RSNO) from NaNO$_{2}$ and thiols in aqueous buffer of neutral pH is reported. Equimolar amounts of NaNO$_{2}$ and thiol are added to a 100-$\mu $M Na$_{4}$EDTA-containing Na$_{2}$HPO$_{4}$ buffer (100 mM, pH 7.4). Samples are set into liquid nitrogen for 1 min and then thawed to room temperature or in an ice bath. Dependent upon the RSNO, repetition of the procedure may be required. This method may be of particular importance when the classical acid-based method fails or releases harmful gases such as H$_{2}$S.


Synthesis And Biological Evaluation Of A New Series Of 4-Alkoxy-2-Arylquinoline Derivatives As Potential Antituberculosis Agents, Gonca Tosun, Tayfun Arslan, Zeynep İskefi̇yeli̇, Murat Küçük, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2015

Synthesis And Biological Evaluation Of A New Series Of 4-Alkoxy-2-Arylquinoline Derivatives As Potential Antituberculosis Agents, Gonca Tosun, Tayfun Arslan, Zeynep İskefi̇yeli̇, Murat Küçük, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

Three new series of 33 quinolone compounds, 2-(2-, 3-, and 4-fluorophenyl)-4-O-alkyl(C$_{5-15})$quinolines (7a-k, 8a-k, and 9a-k), were synthesized from 2-(2-, 3-, and 4-fluorophenyl)-2,3-dihydroquinolin-4(1H)-one (4, 5, and 6) by the reaction of alkyl halides under basic conditions in DMF. The new compounds 7a-k, 8a-k, and 9a-k were synthesized from flavonones 4-6, which can be considered new precursors for quinoline synthesis through a one-step reaction. All the target compounds (7a-k, 8a-k, and 9a-k) were evaluated for their in vitro antimicrobial activity against nine test microorganisms. They showed the most activity against Mycobacterium smegmatis with minimum inhibitory concentrations (MIC) of 62.5-500 $\mu $g/mL, indicating …


Tetraphenylsilane Group Containing Carbazoles As High Triplet Energy Host Materials For Solution-Processable Pholeds, Sali̇ha Öner, İlker Öner, Haydar Akdağ, Canan Varlikli Jan 2015

Tetraphenylsilane Group Containing Carbazoles As High Triplet Energy Host Materials For Solution-Processable Pholeds, Sali̇ha Öner, İlker Öner, Haydar Akdağ, Canan Varlikli

Turkish Journal of Chemistry

A series of solution processable, wide band-gap host materials composed of carbazole and tetraphenylsilane groups were designed and synthesized. Their thermal, electrochemical, and photophysical properties were fully investigated. The introduction of bulky tetraphenylsilane and \textit{tert}-butyl groups around the carbazole led to high glass transition temperatures (T$_{g})$ between 120 and 204 $^{\circ}$C. The triplet energies (E$_{T})$ of the synthesized materials were examined by low temperature (77 K) photoluminescence studies and determined as E$_{T}>$ 2.6 for all compounds. Phosphorescent organic light-emitting devices with the ITO/PEDOT:PSS/EML/TPBi/Cs$_{2}$CO$_{3}$/Al device structure were fabricated by using synthesized materials as the host and two kinds of phosphorescent …


Solid-Phase Total Synthesis Of Cyclic Peptide Brachystemin A And Its Immunomodulating Activity, Zafar Ali Shah, Almas Jabeen, Samreen Soomro, M.Ahmed Mesaik, M.Iqbal Choudhary, Farzana Shaheen Jan 2015

Solid-Phase Total Synthesis Of Cyclic Peptide Brachystemin A And Its Immunomodulating Activity, Zafar Ali Shah, Almas Jabeen, Samreen Soomro, M.Ahmed Mesaik, M.Iqbal Choudhary, Farzana Shaheen

Turkish Journal of Chemistry

Brachystemin A (\textbf{1}) is a biologically active peptide from a Chinese traditional plant \textit{Brachystemma calycinum} D. Don. (Caryophyllaceae). The current study describes the complete solid-phase total synthesis of peptide \textbf{1} by using Kenner's sulfonamide safety-catch linker strategy. It was identified by QTOF/MS data and NMR studies. Synthetic peptide \textbf{1} was tested for its immunomodulatory effect on different inflammatory parameters, including production of inflammatory cytokines, interleukin 2 (IL-2), tumor necrosis factor-$\alpha $ (TNF-$\alpha )$, and interleukin-1$\beta $ (IL-1$\beta )$, and generation of nitric oxide (NO$^{.})$. The synthetic peptide \textbf{1} showed a moderate to low level of inhibition on the production of …


Influence Of Acid And Heavy Metal Cation Exchange Treatments On Methane Adsorption Properties Of Mordenite, Meryem Sakizci, Leyla Özgül Kilinç Jan 2015

Influence Of Acid And Heavy Metal Cation Exchange Treatments On Methane Adsorption Properties Of Mordenite, Meryem Sakizci, Leyla Özgül Kilinç

Turkish Journal of Chemistry

In this study, the adsorption of methane (CH$_{4})$ capacities onto natural mordenite obtained from \.{I}zmir, Turkey, and its cationic forms (CuM, AgM, FeM, and HM samples) were investigated at the temperatures of 0 and 25 $^{\circ}$C up to 100 kPa. Natural and modified samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FT-IR), thermogravimetry (TG-DTG), differential thermal analysis (DTA), scanning electron microscopy (SEM) coupled with energy dispersion spectroscopy (EDS), and N$_{2}$ adsorption methods. Quantitative XRD analysis showed that the major component of the natural zeolite was mordenite, together with minor amounts of quartz, feldspar, and clay …


New Tetrazolic Azo Dyes Linked To (Thio)Barbiturate And Electron-Rich Aromatics As Potential Antimicrobial Agents, Nader Noroozi Pesyan, Davoud Soleimani, Nima Hosseini Jazani Jan 2015

New Tetrazolic Azo Dyes Linked To (Thio)Barbiturate And Electron-Rich Aromatics As Potential Antimicrobial Agents, Nader Noroozi Pesyan, Davoud Soleimani, Nima Hosseini Jazani

Turkish Journal of Chemistry

A series of new tetrazolic azo dyes based on (thio)barbiturate and electron-rich aromatics were synthesized in excellent yield. The electron-donor and tetrazole ring moieties were linked by a $p$-phenylazo bridge and the structural characterizations were achieved by FT IR, $^{1}$H and $^{13}$C NMR, and UV-visible spectrometry. The antibacterial activity of the synthesized compounds was tested against gram-positive and gram-negative bacterial strains, namely \textit{Acinetobacter calcoaceticus} (ATCC23055), \textit{Escherichia coli} (ATCC2592), \textit{Pseudomonas aeruginosa} (ATCC27853), and \textit{Staphylococcus aureus} (ATCC25923). As a result, potential antimicrobial effects were seen for some of the synthesized compounds.


Preparation And Physicochemical Characterizations Of Solid Lipid Nanoparticles Containing Dotap$^®$ For Dna Delivery, Gülay Büyükköroğlu, Emi̇ne Yasemi̇n Yazan, Ayşe Fi̇li̇z Öner Jan 2015

Preparation And Physicochemical Characterizations Of Solid Lipid Nanoparticles Containing Dotap$^®$ For Dna Delivery, Gülay Büyükköroğlu, Emi̇ne Yasemi̇n Yazan, Ayşe Fi̇li̇z Öner

Turkish Journal of Chemistry

The aim of this study was to prepare and evaluate stable cationic solid lipid nanoparticles (SLNs) as colloidal carriers for gene therapy. SLNs were mainly composed of three different biocompatible and biodegradable matrix lipids called tripalmitin, glyceryl dibehenate, and triglyceride, all containing the cationic lipid $N$-(1-(2,3-dioleoyloxy)propyl)-$N,N,N$-trimethylammonium (DOTAP$^®$). Each of these SLNs were divided into three parts and characterized by applying different processes: Part I was autoclaved (121 $^{\circ}$C, 15 min), Part II was lyophilized (5 mbar, --50 $^{\circ}$C), and Part III was kept in its intact form. These parts were stored at 4 $^{\circ}$C, 25 $^{\circ}$C (room temp.), and 40 …


Spectrophotometric Determination Of Iron Species Using Ionic Liquid Ultrasound Assisted Dispersive Liquid--Liquid Microextraction, Alireza Bazmandegan, Ali Mohammad Haji Shabani, Sayessteh Dadfarnia, Mahboubeh Saeidi, Masoud Rohani Moghadam Jan 2015

Spectrophotometric Determination Of Iron Species Using Ionic Liquid Ultrasound Assisted Dispersive Liquid--Liquid Microextraction, Alireza Bazmandegan, Ali Mohammad Haji Shabani, Sayessteh Dadfarnia, Mahboubeh Saeidi, Masoud Rohani Moghadam

Turkish Journal of Chemistry

A simple and efficient method for speciation and determination of iron in different water samples was developed. The method is based on ionic liquid ultrasound assisted dispersive liquid--liquid microextraction (IL-USA-DLLME) followed by spectrophotometric determination. Fe(II) is complexed with 2,4,6-tri(2'-pyridyl)-l,3,5-triazine (TPTZ{)}, neutralized through ion pair formation with sodium dodecyl sulfate (SDS) and extracted into 1-hexyl-3-methylimidazolium hexafluorophosphate [C$_{6}$MIM][PF$_{6}$]. Total iron amount was determined after reduction of Fe(III) to Fe(II) with hydroxylamine hydrochloride. The concentration of Fe(III) was determined from the difference of concentration of total iron and Fe(II). The important parameters such as the type and volume of the extraction solvent, pH, …


Contribution Of Heterobifunctional Ligands To Transition Metal-Catalysed C--C Coupling Reactions, Agnes Labande, Eric Deydier, Eric Manoury, Jean-Claude Daran, Catherine Audin, Rinaldo Poli Jan 2015

Contribution Of Heterobifunctional Ligands To Transition Metal-Catalysed C--C Coupling Reactions, Agnes Labande, Eric Deydier, Eric Manoury, Jean-Claude Daran, Catherine Audin, Rinaldo Poli

Turkish Journal of Chemistry

In this account the authors' latest results in C-C coupling catalysis are reviewed. First, an efficient catalytic system for the Kumada-Tamao-Corriu coupling reaction based on NHC-phosphine (NHC = N-heterocyclic carbene) nickel complexes is presented. Then the use of palladium complexes of chiral ferrocenyl NHC-phosphines in the asymmetric Suzuki-Miyaura coupling reaction is reported. High catalytic activities and moderate enantioselectivities (ee up to 46%) were obtained. Chiral ferrocenyl phosphine-ethers were also tested in the asymmetric Suzuki-Miyaura reaction yielding good activities and moderate enantioselectivities (ee up to 37%). Finally, the original synthesis of a ferrocenyl rhodium(III) complex and its successful use as catalyst …


Sonogashira Reactions For The Synthesis Of Polarized Pentacene Derivatives, Stephane Schweizer, Guillaume Erbland, Philippe Bisseret, Jacques Lalevee, Didier Le Nouen, Nicolas Blanchard Jan 2015

Sonogashira Reactions For The Synthesis Of Polarized Pentacene Derivatives, Stephane Schweizer, Guillaume Erbland, Philippe Bisseret, Jacques Lalevee, Didier Le Nouen, Nicolas Blanchard

Turkish Journal of Chemistry

Five dissymmetrically functionalized anthracene analogues (3a-e) were synthesized from commercially available 9,10-dibromoanthracene through an efficient bromine-iodine exchange followed by two successive Sonogashira coupling reactions. The resulting TMS-anthracene analogues are interesting building blocks for the preparation of highly $\pi$-conjugated dissymmetric pentacene-based dyads, which could be used as active semiconducting layers for organic field-effect transistors (OFETs).


Reactivity Of The 2-Aryl-6,8-Dibromo-2,3-Dihydroquinolin-4(1$H)$-Ones In A Palladium Catalyzed Sonogashira Cross-Coupling Reaction, Malose Jack Mphahlele, Felix Adetunji Oyeyiola Jan 2015

Reactivity Of The 2-Aryl-6,8-Dibromo-2,3-Dihydroquinolin-4(1$H)$-Ones In A Palladium Catalyzed Sonogashira Cross-Coupling Reaction, Malose Jack Mphahlele, Felix Adetunji Oyeyiola

Turkish Journal of Chemistry

Pd/C-PPh$_{3}$--CuI catalyzed Sonogashira cross-coupling of the 2-aryl-6,8-dibromo-2,3-dihydroquinolin-4(1$H)$-ones with phenyl acetylene or 3-butyn-1-ol afforded the corresponding 8-alkynylated quinolin-4(1$H)$-one derivatives, exclusively. Double carbo-substitution to afford the 6,8-dialkynyl derivatives was observed when PdCl$_{2}$(PPh$_{3})_{2}$ was used as Pd(0) source. The monoalkynylated derivatives were, in turn, subjected to PdCl$_{2}$ in acetonitrile under reflux to afford either the corresponding 2,4-diaryl-8-bromopyrrolo[3,2,1-\textit{ij}]quinolinones or the 8-(4-hydroxybutanoyl)-substituted quinolinone derivatives, exclusively. Suzuki--Miyaura cross-coupling of the 2-aryl-6-bromo-8-(alkynyl)quinolin-4-ones afforded the 2,4,8-trisubstituted pyrrolo[3,2,1-\textit{ij}]quinolin-6-ones.


Efficient C--C Cross-Coupling Reactions By (Isatin)-Schiff Base Functionalized Magnetic Nanoparticle-Supported Cu(Ii) Acetate As A Magnetically Recoverable Catalyst, Seyedeh Simin Miri, Mehdi Khoobi, Fatemeh Ashouri, Farnaz Jafarpour, Parviz Rashidi Ranjbar, Abbas Shafiee Jan 2015

Efficient C--C Cross-Coupling Reactions By (Isatin)-Schiff Base Functionalized Magnetic Nanoparticle-Supported Cu(Ii) Acetate As A Magnetically Recoverable Catalyst, Seyedeh Simin Miri, Mehdi Khoobi, Fatemeh Ashouri, Farnaz Jafarpour, Parviz Rashidi Ranjbar, Abbas Shafiee

Turkish Journal of Chemistry

Copper catalysts were simply fabricated through surface modification of superparamagnetic iron nanoparticles with indoline-2,3-dione(isatin)-Schiff-base and interaction with Cu from low-cost commercially available starting materials. Catalysts were characterized using atomic absorption spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, UV/Vis spectroscopy, scanning electron microscopy, and transmission electron microscopy. These catalysts showed high efficiency for phosphine-free Mizoroki--Heck and Suzuki--Miyaura cross-coupling reactions with good diversity and generality. The catalysts could be easily recovered and reused several times without a significant loss in their catalytic activity and stability.


Synthesis, Molecular Docking, And Antitumoral Activity Of Alnustone-Like Compounds Against Estrogen Receptor Alpha-Positive Human Breast Cancer, Kaan Küçükoğlu, Hati̇ce Seçi̇nti̇, Aykut Özgür, Hasan Seçen, Yusuf Tutar Jan 2015

Synthesis, Molecular Docking, And Antitumoral Activity Of Alnustone-Like Compounds Against Estrogen Receptor Alpha-Positive Human Breast Cancer, Kaan Küçükoğlu, Hati̇ce Seçi̇nti̇, Aykut Özgür, Hasan Seçen, Yusuf Tutar

Turkish Journal of Chemistry

Alnustone-like compounds are promising inhibitors for estrogen receptor \alpha (ER-\alpha), which is a novel cancer therapeutic target. Therefore, 10 alnustone-like compounds with substituents at the phenyl rings were synthesized by condensation of 4-phenyl-2-butanones and cinnamaldehydes via in situ enamination. The compounds displayed either protective activity or inhibited cell growth and proliferation of human breast cancer cells. Molecular docking studies indicated that the synthesized compounds interact with ER-\alpha efficiently. In this work, the protective and inhibitive roles of the synthesized compounds were related to their functional groups and to their binding mode of action on ER-\alpha protein. The compounds are potential …


Enzyme-Assisted Modification Of Cellulose/Chitin Fibers With Nipaam, Anamaria Irimia, Emilia Csiszar, Marius Dobromir, Florica Doroftei, Cornelia Vasile Jan 2015

Enzyme-Assisted Modification Of Cellulose/Chitin Fibers With Nipaam, Anamaria Irimia, Emilia Csiszar, Marius Dobromir, Florica Doroftei, Cornelia Vasile

Turkish Journal of Chemistry

Coating processes are applied in order to improve coating adhesion and resistance to degradation. Covalently bound organic coatings rather than merely physically bound ones assure stable modification. In this study a novel two-step process was developed to modify cellulose/chitin mix fibers consisting of enzymatic activation with a commercial cellulase, followed by a coupling reaction with N-isopropylacrylamide (or poly (N-isopropylacrylamide)) in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS). Both enzyme-activated and subsequently modified samples were characterized by ATR-FTIR, XPS, and SEM. All obtained results confirm the structural and morphological changes of the fiber surface after the application of the two-step …


Synthesis And Biological Evaluation Of Novel Fused Triazolo[4,3-$A$] Pyrimidinones, Ikhlass Abbas, Sobhi Gomha, Mohamed Elneairy, Mahmoud Elaasser, Bazada Mabrouk Jan 2015

Synthesis And Biological Evaluation Of Novel Fused Triazolo[4,3-$A$] Pyrimidinones, Ikhlass Abbas, Sobhi Gomha, Mohamed Elneairy, Mahmoud Elaasser, Bazada Mabrouk

Turkish Journal of Chemistry

The reaction of thione 3 or its 2-methylthio derivative 4 with hydrazonoyl halides 5a-l, in the presence of triethylamine, yielded the corresponding triazolo[4,3-$a$]pyrimidin-5(1$H)$-ones 8a-l. The structure of compounds 8a-l was further confirmed by the reaction of 3 with the appropriate active chloromethylenes 11a-c followed by coupling of the products with benzenediazonium chloride to afford the azo-coupling products 6b, f, and j, which were converted in situ to 8b, f, and j. 2-Hydrazinyl-pyrido[3',2':4,5]thieno[3,2-$d$]pyrimidin-4(3$H)$-one (13) was prepared and condensed with different aldehydes 14a-f to give the corresponding hydrazone derivatives 15a-f. Oxidative cyclization of the hydrazones 15a-f give the corresponding triazolo[4,3-$a$] pyrimidin-5(1$H)$-one derivatives …


A Green Light Emitting Polymer In A Pmma Matrix: Oligo(Azomethine-Ether) With Benzothiazole Moieties, Mehmet Yildirim, İsmet Kaya Jan 2015

A Green Light Emitting Polymer In A Pmma Matrix: Oligo(Azomethine-Ether) With Benzothiazole Moieties, Mehmet Yildirim, İsmet Kaya

Turkish Journal of Chemistry

This study aimed to synthesize an oligo(azomethine-ether) with benzothiazole moiety in organic medium by means of chemical oxidative polycondensation (OP). Optical properties were examined by photoluminescence (PL) and UV-Vis measurements both in solutions and solid film involved a poly (methyl methacrylate) (PMMA) matrix. Oligomer film in the PMMA matrix emitted a fine green light with a fluorescence quantum yield (QY) of 3.30%. Spectral and thermal observations showed a high rate of C--O--C coupling (cross-linking) for the oligomer. SEC results indicated low molecular weight (\sim3200--4650 g mol^{-1}) and the oligomer was soluble in organic solvents with high polarity. Electrochemical behavior was …


Three-Component Synthesis Of Cyclic $\Beta $-Aminoesters Using Ceo$_{2}$ Nanoparticles As An Efficient And Reusable Catalyst, Javad Safaei Ghomi, Sima Kalhor, Hossein Shahbazi-Alavi, Mehrnoosh Asgari-Kheirabadi Jan 2015

Three-Component Synthesis Of Cyclic $\Beta $-Aminoesters Using Ceo$_{2}$ Nanoparticles As An Efficient And Reusable Catalyst, Javad Safaei Ghomi, Sima Kalhor, Hossein Shahbazi-Alavi, Mehrnoosh Asgari-Kheirabadi

Turkish Journal of Chemistry

CeO$_{2}$ nanoparticles were used as an efficient catalyst for the preparation of cyclic $\beta $-aminoesters by three-component reaction between primary amines, ethyl acetoacetate, and chalcones in ethanol. Atom economy, low catalyst loading, reusable catalyst, and high yields of products are some of the important features of this protocol.


Synthesis And In Vitro Cytotoxic Activity Of Novel Pyrazolo[1,5-$A$]Pyrimidines And Related Schiff Bases, Ashraf Sayed Hassan, Taghrid Shoukry Hafez, Souad Abdel Meguid Osman, Mamdouh Moawad Ali Jan 2015

Synthesis And In Vitro Cytotoxic Activity Of Novel Pyrazolo[1,5-$A$]Pyrimidines And Related Schiff Bases, Ashraf Sayed Hassan, Taghrid Shoukry Hafez, Souad Abdel Meguid Osman, Mamdouh Moawad Ali

Turkish Journal of Chemistry

The reaction of 5-amino-3-(4-methoxyphenylamino)-$N$-aryl-1$H$-pyrazole-4-carboxamides \textbf{1a}--\textbf{c} with ethyl acetoacetate \textbf{2} and 2-(4-fluorobenzylidene)malononitrile \textbf{6} yielded pyrazolo[1,5-$a$]pyrimidines \textbf{5a}--\textbf{c} and \textbf{9a}--\textbf{c}, respectively. On the other hand, Schiff bases \textbf{11a}--\textbf{f} were obtained upon treatment of carboxamides \textbf{1a}--\textbf{c} with some selected aldehydes \textbf{10a }and\textbf{ b}. The newly synthesized compounds were characterized and confirmed by analytical and spectroscopic data (IR, MS, $^{1}$H NMR, and $^{13}$C NMR). Pyrazolo[1,5-$a$]pyrimidines \textbf{5a}--\textbf{c} and \textbf{9a}--\textbf{c} and Schiff bases \textbf{11b}--\textbf{f} were investigated for their cytotoxicity against four human cancer cell lines (colon HCT116, lung A549, breast MCF-7, and liver HepG2) according to SRB assay and the structure--activity relationship was discussed.


Palladium-Catalyzed Ligand-Free And Efficient Suzuki--Miyaura Reaction Of $N$-Methyliminodiacetic Acid Boronates In Water, Chun Liu, Xinmin Li, Xinnan Wang, Jieshan Qiu Jan 2015

Palladium-Catalyzed Ligand-Free And Efficient Suzuki--Miyaura Reaction Of $N$-Methyliminodiacetic Acid Boronates In Water, Chun Liu, Xinmin Li, Xinnan Wang, Jieshan Qiu

Turkish Journal of Chemistry

A green and efficient protocol has been developed for the Pd(OAc)$_{2}$-catalyzed ligand-free Suzuki--Miyaura reaction of $N$-methyliminodiacetic acid (MIDA) boronates in water. In the presence of Pd(OAc)$_{2}$ as a catalyst and ($i$-Pr)$_{2}$NH as a base, the cross-coupling reactions of aryl bromides with aryl MIDA boronates proceeded smoothly in water without any surfactant, and various functional groups were tolerated under the optimized conditions.


Copper-Free Sonogashira Cross-Coupling Reactions Catalyzed By An Efficient Dimeric C,N-Palladacycle In Dmf/H$_{2}$O, Kazem Karami, Nasrin Haghighat Naeini Jan 2015

Copper-Free Sonogashira Cross-Coupling Reactions Catalyzed By An Efficient Dimeric C,N-Palladacycle In Dmf/H$_{2}$O, Kazem Karami, Nasrin Haghighat Naeini

Turkish Journal of Chemistry

Very small concentrations of a dimeric C,N-palladacycle were used as an efficient homogeneous catalyst for Sonogashira cross-coupling reactions between various aryl halides and phenylacetylene. The catalytic reactions were performed without the need for copper in DMF/H$_{2}$O. This catalytic system shows excellent yields for aryl iodides and bromides and even in the case of aryl chlorides.


Electrochemical Monitoring Of The Interaction Between Mitomycin C And Dna At Chitosan--Carbon Nanotube Composite Modified Electrodes, Pembe Ece Canavar, Ece Ekşi̇n, Kadri̇ye Arzum Erdem Gürsan Jan 2015

Electrochemical Monitoring Of The Interaction Between Mitomycin C And Dna At Chitosan--Carbon Nanotube Composite Modified Electrodes, Pembe Ece Canavar, Ece Ekşi̇n, Kadri̇ye Arzum Erdem Gürsan

Turkish Journal of Chemistry

Single-walled carbon nanotube (CNT) and chitosan composite (chitosan*CNT) based sensors were developed as DNA biosensors, and then they were applied for electrochemical investigation of the interaction between the anticancer drug mitomycin C (MC) and DNA. The oxidation signals of MC and guanine were monitored before and after the interaction process by differential pulse voltammetry (DPV). The DPV results were in good agreement with those of electrochemical impedance spectroscopy (EIS). Analytical parameters such as DNA concentration, MC concentration, and MC interaction time with DNA were optimized. The detection limits were 6.85 \mu g/mL for DNA and 11.01 \mu g/mL for MC.


Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan Jan 2015

Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan

Turkish Journal of Chemistry

A novel amperometric ethanol biosensor with alcohol dehydrogenase (ADH) and nicotinamide adenine dinucleotide (NAD^+) on polypyrrole--polyvinylsulfonate (PPy-PVS) film was accomplished. Meldola's blue (MB) was used as a mediator; it can facilitate the electron transfer that involves a chemical interaction between the electrode surface and NADH. Determination of ethanol was carried out by the oxidation of MB at --0.072 V vs. Ag/AgCl. The effects of pH and temperature were investigated and optimum parameters were found to be 7.0 and 40 °C, respectively. There are 2 linear parts at 1.0 \mu M--10.0 \mu M (R^2 = 0.993) and 0.01 mM--0.1 mM (R^2 …


Synthesis Of Methyl 4-(9h-Carbazole-9-Carbanothioylthio) Benzoate: Electropolymerization And Impedimetric Study, Murat Ateş, Nesi̇mi̇ Uludağ, Fati̇h Arican, Tolga Karazehi̇r Jan 2015

Synthesis Of Methyl 4-(9h-Carbazole-9-Carbanothioylthio) Benzoate: Electropolymerization And Impedimetric Study, Murat Ateş, Nesi̇mi̇ Uludağ, Fati̇h Arican, Tolga Karazehi̇r

Turkish Journal of Chemistry

Methyl 4-((9H-(carbazole-9-carbanothioylthio) benzoate (MCzCTB) was chemically synthesized and characterized by FTIR, ^1H NMR, and ^{13}C NMR. A novel synthesized monomer was electropolymerized on a glassy carbon electrode (GCE) in various initial molar concentrations of [MCzCTB]_0= 1, 3, 5, and 10 mM in 0.1 M NaClO_4/CH_3CN and 1 M H_2SO_4. P(MCzCTB)/GCE was characterized by cyclic voltammetry, Fourier transform infrared-attenuated transmittance reflectance, scanning electron microscopy-energy dispersive X-ray, and electrochemical impedance spectroscopy. The capacitive behavior of the modified electrode was obtained by Nyquist, Bode-magnitude, and Bode-phase plots. The highest capacitance at low frequency was obtained as \sim 53.1 mF cm^{-2} from Nyquist plot …