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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Molecular Modeling Studies Of Naproxen-Based Acyl Hydrazone Derivatives, Tuğba Taşkin Tok, Özgün Özaşik, Deni̇z Sarigöl, Ayşe Uzgören Baran Jan 2015

Synthesis And Molecular Modeling Studies Of Naproxen-Based Acyl Hydrazone Derivatives, Tuğba Taşkin Tok, Özgün Özaşik, Deni̇z Sarigöl, Ayşe Uzgören Baran

Turkish Journal of Chemistry

A series of N-acylhydrazone derivatives (2a--2p) containing 6-methoxy-naphthalene and acylhydrazone moieties were synthesized in good yield using microwave irradiation and developed as potential COX-2 inhibitors. Furthermore, the interactions between COX-2 and the compounds were examined in detail by molecular modeling studies such as structure--activity relationship and molecular docking performed using Gaussian 09 and Discovery Studio 3.5. As a result, it was found that N-acylhydrazone compounds displayed a different mechanism than SC-558 as COX-2 inhibitor by binding to different active sites of the protein, COX-2. Compound 2c would be a good COX-2 inhibitor candidate for preclinical studies.


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.


Kinetics And Performance Studies Of A Switchable Solvent Tmg (1,1,3,3-Tetramethylguanidine)/1-Propanol/Carbon Dioxide System, Özge Yüksel, Mustafa Çağdaş Öztürk, Ayça Şeker, Erdoğan Alper Jan 2015

Kinetics And Performance Studies Of A Switchable Solvent Tmg (1,1,3,3-Tetramethylguanidine)/1-Propanol/Carbon Dioxide System, Özge Yüksel, Mustafa Çağdaş Öztürk, Ayça Şeker, Erdoğan Alper

Turkish Journal of Chemistry

The rate constants and the activation energies of the reaction between carbon dioxide and 1,1,3,3-tetramethylguanidine (TMG) in 1-propanol solution were measured by a stopped-flow technique at a temperature range of 288--308 K and at a TMG concentration range of 2.5--10.0 wt %. Based on the pseudo-first-order reaction for CO_2, the reaction was modeled by a termolecular reaction mechanism, which resulted in a rate constant of 199.30 m^3 kmol^{-1} s^{-1} at 298 K. The activation energies were 5.19 kJ/mol and 5.26 kJ/mol at 2.5 and 5.0 wt % TMG, respectively. In addition, carbon dioxide absorption capacity was investigated using a gas--liquid …


Dual Effect Of Coumarin Benzimidazolium Ionic Salt Covalently Bonded On A Silica Network, Ahmet Gültek, Davut Aksüt, Turgay Seçki̇n, Emre Bi̇rhanli, Mert Olgun Karataş, Bülent Alici Jan 2015

Dual Effect Of Coumarin Benzimidazolium Ionic Salt Covalently Bonded On A Silica Network, Ahmet Gültek, Davut Aksüt, Turgay Seçki̇n, Emre Bi̇rhanli, Mert Olgun Karataş, Bülent Alici

Turkish Journal of Chemistry

Synthesis of the ionic liquid 1-allyl-3-(4-methyl-7,8-dihydroxy-2H-chromen-2-one) benzimidazolium chloride followed by the conversion of ammonium salts on the imidazole ring hooked to the coumarin group was modified by postmodification of the silica matrix where 3-chloropropyltrimethoxysilane was used as not only a surface modification agent, but also as an ATRP halogen source. The synergetic effect of charged ammonium groups as well as hydroxyl groups present on the coumarin was investigated in terms of ATRP polymerization. The results confirmed that brush polymers show outstanding antibacterial effects against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.


Reduction Behavior Of Fenoxaprop-P-Ethyl And Its Voltammetric Determination, Zeki̇ Eş, İbrahi̇m Hüdai̇ Taşdemi̇r Jan 2015

Reduction Behavior Of Fenoxaprop-P-Ethyl And Its Voltammetric Determination, Zeki̇ Eş, İbrahi̇m Hüdai̇ Taşdemi̇r

Turkish Journal of Chemistry

The reduction behavior of fenoxaprop-p-ethyl (FNX) was studied on a hanging mercury drop electrode. FNX showed 2 reduction peaks at about --0.7 V and at about --0.9 V versus Ag/AgCl/3.0 M KCl in Britton--Robinson buffer at pH 4.8. Both reductions were irreversible and adsorption was effective. The reduction peaks were assigned to the reduction of C=N to CH--NH and the reduction of C=O to CH--OH. Square-wave voltammetry has been proposed and validated for quantification of FNX in different samples. The linear working range was established as 0.30--15.0 \mu M. Limit of detection and limit of quantification were calculated as 0.07 …


Synthesis And Characterization Of Substituted Benzimidazole Co(Ii), Fe(Ii), And Zn(Ii) Complexes And Structural Characterization Of Dichlorobis{1-[2-(1-Piperidinyl)Ethyl]-1h-Benzimidazole-_Kn^3} Zinc(Ii), Hasan Küçükbay, Ülkü Yilmaz, Mehmet Akkurt, Orhan Büyükgüngör Jan 2015

Synthesis And Characterization Of Substituted Benzimidazole Co(Ii), Fe(Ii), And Zn(Ii) Complexes And Structural Characterization Of Dichlorobis{1-[2-(1-Piperidinyl)Ethyl]-1h-Benzimidazole-_Kn^3} Zinc(Ii), Hasan Küçükbay, Ülkü Yilmaz, Mehmet Akkurt, Orhan Büyükgüngör

Turkish Journal of Chemistry

The Co(II), Fe(II), and Zn(II) complexes of 1-(3-phenyl)propylbenzimidazole (PPBI), 5-nitro-1-(3-phenyl) propylbenzimidazole (PPNBI), 1-[2-(4-morpholinyl)ethyl]benzimidazole (MEBI), 1-[2-(1-piperidinyl)ethyl]benzimidazole (PEBI), and 5-nitro-1-[2-(1-piperidinyl)ethyl]benzimidazole (PENBI) were synthesized and characterized by ^1H NMR, ^{13}C NMR, and elemental analyses. The magnitudes of the magnetic moments for paramagnetic complexes were between 4.07 and 5.11 B.M. Moreover, the crystal structure of dichlorobis{1-[2-(1-piperidinyl)ethyl]-1H-benzimidazole-_KN^3} zinc(II) was determined by single crystal X-ray diffraction.


Effect Of Acrylic Acid Feed Contents Of Microgels On Catalytic Activity Of Silver Nanoparticles Fabricated Hybrid Microgels, Zahoor Hussain Farooqi, Shanza Rauf Khan, Robina Begum, Farah Kanwal, Ahsan Sharif, Ejaz Ahmed, Shumaila Majeed, Kiran Ejaz, Aysha Ijaz Jan 2015

Effect Of Acrylic Acid Feed Contents Of Microgels On Catalytic Activity Of Silver Nanoparticles Fabricated Hybrid Microgels, Zahoor Hussain Farooqi, Shanza Rauf Khan, Robina Begum, Farah Kanwal, Ahsan Sharif, Ejaz Ahmed, Shumaila Majeed, Kiran Ejaz, Aysha Ijaz

Turkish Journal of Chemistry

We synthesized poly(N-isopropylacrylamide-co-acrylic acid) microgels with 1, 3, 5, and 7 mol percentage of acrylic acid. Silver nanoparticles were fabricated inside these microgels at room temperature. Pure microgels were characterized by Fourier transform infrared (FTIR) spectroscopy and dynamic light scattering (DLS). Hybrid microgels were characterized by UV-Visible spectroscopy. The size of the silver nanoparticles increased with an increase in the content of acrylic acid. Catalytic activity of these hybrid microgels was investigated using UV-Visible spectrophotometry. Induction time decreased from 8.8 to 2.6 min and the value of apparent rate constant decreased from 0.226 to 0.109 min^{-1}, when the content of …


Synthesis, Properties, And Electrochemistry Of A Photochromic Compound Based On Dithienylethene And Prodot, Melek Pamuk Algi, Ati̇lla Ci̇haner, Fati̇h Algi Jan 2015

Synthesis, Properties, And Electrochemistry Of A Photochromic Compound Based On Dithienylethene And Prodot, Melek Pamuk Algi, Ati̇lla Ci̇haner, Fati̇h Algi

Turkish Journal of Chemistry

The synthesis, photochromic features, and electrochemistry of a novel material based on dithienylethene (DTE) and 3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine (didecyl-ProDOT) units are described. It is noteworthy that 1,2-bis(5-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-2-methylthiophen-3-yl)cyclopent-1-ene can be efficiently switched between open and closed states by light in both solution and in the solid poly(methyl metacrylate) (PMMA) matrix. It is also found that the emission of this novel compound can be switched on and off upon irradiation.


Preparation Of Visible Light Sensitive Nano-Sized N-Tio_2 Photocatalysts And Their Photocatalytic Activity Under Visible Light, Young-Gu Kang, Kwang-Hyeok Lee, Hyun-Sik Hahm Jan 2015

Preparation Of Visible Light Sensitive Nano-Sized N-Tio_2 Photocatalysts And Their Photocatalytic Activity Under Visible Light, Young-Gu Kang, Kwang-Hyeok Lee, Hyun-Sik Hahm

Turkish Journal of Chemistry

This study aimed to develop a photocatalyst that responds to visible light. For the preparation of visible light sensitive photocatalysts, N was doped into TiO_2 (N-TiO_2). To inhibit the recombination of excited electrons and holes, transition metals (M = Pt, Cu, Fe, Cr) were loaded on the N-TiO_2. N-TiO_2 nanotubes were also synthesized by a hydrothermal treatment of the prepared N-TiO_2 in a strong basic environment. The prepared photocatalysts were characterized by XRD, FESEM, HRTEM, XPS, and UV/VIS spectrophotometer, and their photocatalytic activity was tested by the photodecomposition of liquid-phase methylene blue and gas-phase acetone.


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 …


Synthesis Of New Oxindole Derivatives Containing Benzothiazole And Thiazolidinone Moieties Using Nano Silica-Bonded 5-N-Propyl-Octahydro-Pyrimido[1,2-A]Azepinium Chloride (Nsb-Dbu) As Catalyst, Robabeh Baharfar, Narges Shariati Jan 2015

Synthesis Of New Oxindole Derivatives Containing Benzothiazole And Thiazolidinone Moieties Using Nano Silica-Bonded 5-N-Propyl-Octahydro-Pyrimido[1,2-A]Azepinium Chloride (Nsb-Dbu) As Catalyst, Robabeh Baharfar, Narges Shariati

Turkish Journal of Chemistry

A facile one-pot synthesis of novel oxindole derivatives bearing benzothiazolylmethyl-2-thioxothiazolidin-4-one was accomplished via one-pot reaction of 5-oxoindolinylidene rhodanine-3-acetic acid derivatives, 2-aminothiophenol, and triphenyl phosphite in the presence of tetrabutylammonium bromide (TBAB) and nano silica-bonded 5-n-propyl-octahydro-pyrimido[1,2-a]azepinium chloride (NSB-DBU) as heterogeneous reusable nanocatalyst. The target compounds were obtained in excellent yields (85%--92%) and short reaction times under fairly mild reaction conditions.


Regiospecific One-Pot, Combinatorial Synthesis Of New Substituted Pyrimido[4,5-C]Pyridazines As Potential Monoamine Oxidase Inhibitors, Mehdi Rimaz, Paria Pourhossein, Behzad Khalili Jan 2015

Regiospecific One-Pot, Combinatorial Synthesis Of New Substituted Pyrimido[4,5-C]Pyridazines As Potential Monoamine Oxidase Inhibitors, Mehdi Rimaz, Paria Pourhossein, Behzad Khalili

Turkish Journal of Chemistry

New 3-aryl-6-methylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones and 3-aryl-6-ethyl-7-thioxo-7,8-dihydropyrimido[4,5-c]pyridazin-5(6H)-ones were efficiently synthesized via a regiospecific one-pot reaction of N-methylbarbituric acid and N-ethyl-2-thiobarbituric acid with various arylglyoxal monohydrates in the presence of hydrazine dihydrochloride in ethanol at 50 °C. The target compounds were obtained in high yields and were regioisomerically pure after recrystallization. These new heterocycles may act as potential MAO_{B} inhibitors.


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.


Effect Of Sonic Treatment On The Permeation Performance Of Cellulose Acetate Membranes Modified By N-Sio_2, Gülsen Asman, Mürvet Kaya, Nursel Pekel Bayramgi̇l Jan 2015

Effect Of Sonic Treatment On The Permeation Performance Of Cellulose Acetate Membranes Modified By N-Sio_2, Gülsen Asman, Mürvet Kaya, Nursel Pekel Bayramgi̇l

Turkish Journal of Chemistry

Cellulose acetate (CA) membranes were modified by nano-silicon dioxide (n-SiO_2), and they were exposed to ultrasonic waves at a frequency of 35 kHz. The effect of sonication on their water sorption tendency and permeation capability was investigated. The characterization of the membranes was done by FTIR and SEM analysis, and the hydrophilic character of the membranes was deduced by swelling studies and contact angle (CAn) measurements. Permeation studies of the membranes were performed by using the diffusion method and theophylline was used as a model chemical in the permeation studies. The results indicated that beside the high hygroscopic property of …


Synthesis And Biological Evaluation Of New Pyridines Containing Imidazole Moiety As Antimicrobial And Anticancer Agents, Ikhlass Abbas, Sobhi Gomha, Mahmoud Elaasser, Mohammed Bauomi Jan 2015

Synthesis And Biological Evaluation Of New Pyridines Containing Imidazole Moiety As Antimicrobial And Anticancer Agents, Ikhlass Abbas, Sobhi Gomha, Mahmoud Elaasser, Mohammed Bauomi

Turkish Journal of Chemistry

The synthesis of a novel series of pyridine and bipyridine derivatives is described via one-pot multicomponent reaction of 5-acetylimidazole, malonitrile (or ethylcyanoacetate or diethylmalonate), substituted benzaldehyde (or terephthaldehyde), and ammonium acetate in good yields. The structures of all the new compounds were elucidated on the basis of elemental analysis and spectral data. The antimicrobial activities of the synthesized compounds were screened and the results showed that most of such compounds exhibit considerable activities. Furthermore, some of the newly synthesized compounds were screened for their anticancer activity against human breast cell line (MCF-7) and liver carcinoma cell line (HEPG2) in comparison …


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 …


Ring Opening And Ring Closure Reactions Of Chromone-3-Carboxylic Acid: Unexpected Routes To Synthesize Functionalized Benzoxocinones And Heteroannulated Pyranochromenes, Magdy Ahmed Ibrahim, Tarik El-Sayed Ali Jan 2015

Ring Opening And Ring Closure Reactions Of Chromone-3-Carboxylic Acid: Unexpected Routes To Synthesize Functionalized Benzoxocinones And Heteroannulated Pyranochromenes, Magdy Ahmed Ibrahim, Tarik El-Sayed Ali

Turkish Journal of Chemistry

Unexpected routes to synthesize functionalized benzoxocinones and heteroannulated pyranochromenes were achieved via transformations of the \gamma-pyrone ring in chromone-3-carboxylic acid throughout its reactions with some acyclic and cyclic carbon nucleophiles. A key part of the reaction mechanisms is discussed. Structures of the new synthesized products were established on the basis of elemental analysis and spectral data (IR, MS, and ^1H and ^{13}C NMR).


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 …


One-Pot And Solvent-Free Synthesis Of 3-(9-Hydroxy-3-Methoxy-7-Aryl-6,7,9,10-Tetrahydro-5$H$-Benzo[$H$]Thiazolo[2,3-$B$]Quinazolin-9-Yl)-2$H$-Chromen-2-Ones And Their Antibacterial Evaluation, Ravibabu Velpula, Janardhan Banothu, Rajitha Gali, Yakaiah Sargam, Rajitha Bavantula Jan 2015

One-Pot And Solvent-Free Synthesis Of 3-(9-Hydroxy-3-Methoxy-7-Aryl-6,7,9,10-Tetrahydro-5$H$-Benzo[$H$]Thiazolo[2,3-$B$]Quinazolin-9-Yl)-2$H$-Chromen-2-Ones And Their Antibacterial Evaluation, Ravibabu Velpula, Janardhan Banothu, Rajitha Gali, Yakaiah Sargam, Rajitha Bavantula

Turkish Journal of Chemistry

A series of 3-(9-hydroxy-3-methoxy-7-aryl-6,7,9,10-tetrahydro-5$H$-benzo[$h$]thiazolo[2,3-$b$]quinazolin-9-yl)-2$H$-chromen-2-ones (5a-j) were synthesized by one-pot multicomponent reaction of 6-methoxy-1-tetralone, aryl aldehydes, and thiourea followed by cyclization with 3-(2-bromoacetyl)-2$H$-chromen-2-one in the presence of a Bronsted solid acid catalyst, poly(4-vinylpyridinium)hydrogen sulfate [P(4-VPH)HSO$_{4}$] (0.015 g), under solvent-free conditions at 120 $^{\circ}$C. All the synthesized compounds were characterized by spectral studies and screened for their in vitro antibacterial activity against S. aureus and B. thuringiensis (gram positive), and E. coli and K. pneumoniae (gram negative) bacterial strains. On comparing with the standard drug gentamicin, compounds derived from 4-methoxy and 3,4,5-trimethoxy benzaldehyde, i.e. 5g and 5h, showed broad spectrum antibacterial activity …


A New And Simple Procedure For The Trace Determination Of Mercury Using Differential Pulse Polarography And Application To A Salt Lake Sample, Güler Somer, A. Cengi̇z Çalişkan, Olcay Şendi̇l Jan 2015

A New And Simple Procedure For The Trace Determination Of Mercury Using Differential Pulse Polarography And Application To A Salt Lake Sample, Güler Somer, A. Cengi̇z Çalişkan, Olcay Şendi̇l

Turkish Journal of Chemistry

A new and simple differential pulse polarographic procedure was established for the trace determination of mercury(II). An indirect method had to be used since no polarographic peak can be observed for its direct determination. According to their standard potentials, the reaction between SO$_{3}^{2-}$ and Hg(II) was suitable. The peak height of sulfite at about -0.70 V (pH 6, 7) was sharp, high, and very reproducible, enabling the accurate determination of low concentrations of Hg(II). It was found that sulfite concentration had to be 3 times larger than mercury at pH 6, in order to have a quantitative reaction. The procedure …


Functional Gold Nanoparticle Coated Surfaces For Ca 125 Cancer Biomarker Detection, İlknur Tunç, Hepi̇ Hari̇ Susapto, Mustafa Özgür Güler Jan 2015

Functional Gold Nanoparticle Coated Surfaces For Ca 125 Cancer Biomarker Detection, İlknur Tunç, Hepi̇ Hari̇ Susapto, Mustafa Özgür Güler

Turkish Journal of Chemistry

Here we describe the detailed characterization of gold nanoparticle (Au Np) functionalized surfaces as a biosensing platform by studying a model streptavidin (SA)-biotin interaction. Conjugation of SA on Au Np immobilized on silicon (Si) and quartz surfaces and its interaction with biotin were characterized by X-ray photoelectron spectroscopy (XPS), UV-Vis spectroscopy, circular dichromism (CD) spectroscopy, and contact angle measurements. The immobilization method and atomic concentrations of Si 2p, Au 4f, S 2p, C 1s, N 1s, and O 1s of the resulting SA-biotin modified Si surface were determined by XPS. The CD spectrum and confocal microscopy imaging confirmed that step-by-step …


Purification, Refolding, And Characterization Of Recombinant Human Paraoxonase-1, Yeli̇z Demi̇r, Şükrü Beydemi̇r Jan 2015

Purification, Refolding, And Characterization Of Recombinant Human Paraoxonase-1, Yeli̇z Demi̇r, Şükrü Beydemi̇r

Turkish Journal of Chemistry

A high density lipoprotein (HDL)-linked enzyme with antioxidant and antiatherogenic properties, paraoxonase-1(PON1), prevents the formation of atherosclerotic lesions in humans. In the present study, a recombinant hPON1 gene was produced using a small ubiquitin-related modifier (SUMO) fusion protein expression system. To that end, the hPON1 gene was amplified from human liver-ready cDNA, cloned into the expression vector pET SUMO, and expressed in Escherichia coli BL21 (DE3). The predominance of the expressed fusion SUMO-hPON1 protein was inclusion bodies and purified using 6xHis affinity chromatography under natural and denaturing conditions. Subsequently, the enzyme was purified and refolded directly on the affinity matrix …


Synthesis And Characterization Of Novel Urea And Thiourea Substitute Cyclotriphosphazene Compounds As Naked-Eye Sensors For F$^{-}$ And Cn$^{-}$ Anions, Hava Özay, Mehmet Yildirim, Özgür Özay Jan 2015

Synthesis And Characterization Of Novel Urea And Thiourea Substitute Cyclotriphosphazene Compounds As Naked-Eye Sensors For F$^{-}$ And Cn$^{-}$ Anions, Hava Özay, Mehmet Yildirim, Özgür Özay

Turkish Journal of Chemistry

Novel hexakisurea and thiourea cyclotriphosphazene compounds (3-7) were synthesized. The structure of all compounds was identified using FT-IR $^{1}$H, $^{13}$C, and $^{31}$P NMR spectroscopy; MALDI-TOF MS; and elemental analysis. The optical sensor properties for anions of 3-7 were investigated using UV-Vis spectroscopy. It was determined that compounds 6 and 7 are spectrophotometric and naked eye sensors for F$^{-}$ and CN$^{-}$ anions, respectively. Sensor properties of these compounds for anions were investigated using UV-Vis spectroscopy. The stoichiometry of host-guest complexes was found to be 1:6.


Microwave-Assisted Regioselective [1,3]-Dipolar Cycloaddition Of 3-Methyl-2-(Substitutedbenzylidene)-5-Oxopyrazolidin-2-Ium-1-Ides To Benzothiophene 1,1-Dioxide, Yaşar Dürüst, Eda Sağirli, Akin Sağirli Jan 2015

Microwave-Assisted Regioselective [1,3]-Dipolar Cycloaddition Of 3-Methyl-2-(Substitutedbenzylidene)-5-Oxopyrazolidin-2-Ium-1-Ides To Benzothiophene 1,1-Dioxide, Yaşar Dürüst, Eda Sağirli, Akin Sağirli

Turkish Journal of Chemistry

A series of pyrazolidinium ylides was reacted with benzothiophene 1,1-dioxide to afford (3R,5S,5aS,10bS)-3-methyl-5-substitutedphenyl-2,3,5,5a-tetrahydrobenzo[4,5]thieno[3,2-c]pyrazolo[1,2-a]pyrazol-1(10bH)-one 6,6-dioxides under microwave irradiation and their structures were identified by means of spectral/physical characteristics including X-ray diffraction data and HRMS measurements.


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 Of 5-Aryl-$N$-(Trichloroacetyl)-1,3,4-Oxadiazole-2-Carboxamide Via Three-Component Reaction Of Trichloroacetyl Isocyanate, ($N$-Isocyanimino)Triphenylphosphorane, And Benzoic Acid Derivatives, Nahid Shajari, Ali Reza Kazemizadeh, Ali Ramazani Jan 2015

Synthesis Of 5-Aryl-$N$-(Trichloroacetyl)-1,3,4-Oxadiazole-2-Carboxamide Via Three-Component Reaction Of Trichloroacetyl Isocyanate, ($N$-Isocyanimino)Triphenylphosphorane, And Benzoic Acid Derivatives, Nahid Shajari, Ali Reza Kazemizadeh, Ali Ramazani

Turkish Journal of Chemistry

The three-component reaction of benzoic acid derivatives, ($N$-isocyanimino)triphenylphosphorane, and trichloroacetyl isocyanate in a 1:1:1 ratio in CH$_{3}$CN occurred at room temperature, and the 5-aryl-$N$-(trichloroacetyl)-1,3,4-oxadiazole-2-carboxamide derivatives produced were formed in high yields. The reaction proceeded smoothly and cleanly under mild reaction conditions and no side reactions were observed. The structures of the products were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, mass spectroscopy, and elemental analysis.


Palladium Nanoparticles Supported On Modified Polystyrene Resin As A Polymeric Catalyst For Sonogashira-Hagihara Coupling Reactions, Bahman Tamami, Fatemeh Nowroozi Dodeji, Soheila Ghasemi Jan 2015

Palladium Nanoparticles Supported On Modified Polystyrene Resin As A Polymeric Catalyst For Sonogashira-Hagihara Coupling Reactions, Bahman Tamami, Fatemeh Nowroozi Dodeji, Soheila Ghasemi

Turkish Journal of Chemistry

Pd(0) nanoparticles supported on modified crosslinked polystyrene were synthesized and characterized. Crosslinked polystyrene was reacted with trioxane and chlorotrimethylsilane in the presence of SnCl$_{4}$ to form Merrifield resin. The Merrifield resin was then converted to polymer-bound $\beta $-aminoalcohol and subsequently to $\beta$-aminophosphinite ligand. This polymeric ligand was reacted with PdCl$_{2}$ to obtain a polymeric Pd(0) complex. The TEM image of the Pd catalyst showed good dispersion of catalytic sites. The Pd catalyst exhibits excellent activity and stability in copper-free Sonogashira-Hagihara cross-coupling reactions under aerobic conditions. This protocol can be applied efficiently to the coupling reactions of chloro- as well as …


A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k Jan 2015

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k

Turkish Journal of Chemistry

A series of new nickel(II) and copper(II) hydrazone complexes \textbf{1--14}, containing a bidentate NO-donor hydrazone ligand, derived from 4-nitrobenzoylhydrazide and several aliphatic and aromatic aldehydes were synthesized, and their chemical structures were confirmed by means of FT-IR, UV-Vis, $^{1}$H and $^{13}$C NMR, mass spectral data, conductance measurements, and elemental analyses. The spectral data of the newly synthesized complexes show the formation of a 1:2 [metal:ligand] ratio. The ligands and their complexes were also investigated for their possible in vitro antimicrobial activities against \textit{S. aureus}, \textit{S. epidermidis}, \textit{E. coli}, \textit{K. pneumonia}, \textit{P. aeruginosa}, \textit{P. mirabilis}, \textit{E. faecalis}, and \textit{C. albicans}. Among …