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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Characterization Of New Thiophene--Benzimidazole-Based Electrochromes, Emi̇ne Gül Cansu Ergün Jan 2018

Synthesis And Characterization Of New Thiophene--Benzimidazole-Based Electrochromes, Emi̇ne Gül Cansu Ergün

Turkish Journal of Chemistry

In the present study, two new donor--acceptor--donor-type molecules were synthesized and the electro-optical properties of the resulting monomers and their corresponding polymers were investigated. Thiophene was selected as the donor unit and cycloheptyl- and cyclooctyl- substituted benzimidazoles were used as the acceptor units. The synthesized monomers and their electrochemically obtained polymers were characterized using cyclic voltammetry and UV-Vis spectrometry. The optical band gap values of the polymers were 1.62 eV and the polymer films changed color to gray upon oxidation, while they were brick red in their neutral states. Moreover, changing the ring size on the acceptor group from seven …


Adsorptive Properties Of Mesoporous Silica Modified With Lewis Base Molecule And Its Application In The Preconcentration Of Cu(Ii), Co(Ii), And Cd(Ii) From Aqueous Media, Janaíne Do Rócio Ivassechen, Alexandre De Oliveira Jorgetto, Marcos Henrique Pereira Wondracek, Adrielli Cristina Peres Da Silva, Luiz Fabrício Zara, Valber De Albuquerque Pedrosa, Bruno Prior Rocha, Margarida Juri Saeki, Gustavo Rocha Castro Jan 2018

Adsorptive Properties Of Mesoporous Silica Modified With Lewis Base Molecule And Its Application In The Preconcentration Of Cu(Ii), Co(Ii), And Cd(Ii) From Aqueous Media, Janaíne Do Rócio Ivassechen, Alexandre De Oliveira Jorgetto, Marcos Henrique Pereira Wondracek, Adrielli Cristina Peres Da Silva, Luiz Fabrício Zara, Valber De Albuquerque Pedrosa, Bruno Prior Rocha, Margarida Juri Saeki, Gustavo Rocha Castro

Turkish Journal of Chemistry

Cocondensation and postfunctionalization methods were employed to synthesize a mesoporous silica with large surface area (795.1 $\pm $ 1.1 m$^{2}$ g$^{-1})$ modified with 4-amino-5-hydrazino-1,2,4-triazole-3-thiol, which was successfully applied to adsorb and preconcentrate Cu(II), Co(II), and Cd(II) from aqueous media. Infrared spectroscopy of the adsorbent material demonstrated N-H stretching bonds related to primary amines existing in the ligand molecule, elemental analysis revealed the presence of 0.132 mmol g$^{-1}$ of nitrogen, scanning electron microscopy indicated globularly shaped particles with average size of 10 $\mu $m, and the point of zero charge was found to be 7.2. Kinetic data were applied to the …


Physicochemical Characterization Of Different Cellulose Polymorphs/Graphene Oxide Composites And Their Antibacterial Activity, Sherif Mohamed Abdel Salam Keshk, Ibrahim Sayed Yahia Jan 2018

Physicochemical Characterization Of Different Cellulose Polymorphs/Graphene Oxide Composites And Their Antibacterial Activity, Sherif Mohamed Abdel Salam Keshk, Ibrahim Sayed Yahia

Turkish Journal of Chemistry

In order to investigate the interaction of graphene oxide (GO) with different cellulose polymorphs (I and II), we synthesized cellulose (I and II)/GO composites using the sonication method. Interestingly, no new peaks were observed in the FT-IR pattern of the cellulose (I and II)/GO composites, indicating that no chemical reactions took place between GO and cellulose. The X-ray diffraction patterns of cellulose I and II/GO composites were slightly different than those observed for cellulose I and II, indicating that some physical interactions occurred between the GO and cellulose. Unexpectedly the $d$-spacing values and the diffraction plane at the high-angle side …


Synthesis Of Quaternized Zinc(Ii) And Cobalt(Ii) Phthalocyanines Bearing Pyridine-2-Yl-Ethynyl Groups And Their Dna Binding Properties, Maryam Moeini Alishah, Hacer Yasemi̇n Yeni̇lmez, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Zehra Altuntaş Bayir Jan 2018

Synthesis Of Quaternized Zinc(Ii) And Cobalt(Ii) Phthalocyanines Bearing Pyridine-2-Yl-Ethynyl Groups And Their Dna Binding Properties, Maryam Moeini Alishah, Hacer Yasemi̇n Yeni̇lmez, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Zehra Altuntaş Bayir

Turkish Journal of Chemistry

The synthesis and biological properties of tetra-substituted zinc and cobalt phthalocyanines bearing ethynylpy- ridine units on the periphery and their quaternized derivatives have been reported. The binding of quaternized ZnPc and CoPc (Q-ZnPc and Q-CoPc) with calf thymus DNA was investigated by UV-Vis spectrophotometric methods and thermodynamics. The mixtures of Q-ZnPc or Q-CoPc and DNA solutions were used to determine the change in the thermal melting temperature of DNA with the thermal denaturation profile. Thermodynamic parameters that show the spontaneity of the reactions between DNA and the quaternized phthalocyanines were investigated. K$_{b}$ binding constants at a degree of 10$^{5}$ and …


Ligand Binding Constants Of The Cucurbit[7]Uril Predicted With Molecular Docking: A Theoretical Study, Balázs Roósz, Tamás Körtvélyesi, Béla Viskolcz Jan 2018

Ligand Binding Constants Of The Cucurbit[7]Uril Predicted With Molecular Docking: A Theoretical Study, Balázs Roósz, Tamás Körtvélyesi, Béla Viskolcz

Turkish Journal of Chemistry

A binding stability order predicting, molecular docking based fast technique was developed for host--guest complexes. Molecular descriptors were applied to ligand molecules to make the binding energy based docking scoring functions more efficient and reach the $\pm $0.50 log K unit theoretical precision for predictions. The goal of this work was to model complexes of cucurbit[7]uril (CB7) as a host molecule with different local anesthetics and choline and phosphonium choline molecules. The guest molecules were docked into the cavity of CB7. The binding free energy maps were correlated by Contact, Grid-Based, Hawkins GB/SA, and AMBER docking scores obtained from UCSF …


Recent Advances In Organ-On-A-Chip Technologies And Future Challenges: A Review, Hüseyi̇n Avci, Fatma Doğan Güzel, Sali̇m Erol, Ali̇ Akpek Jan 2018

Recent Advances In Organ-On-A-Chip Technologies And Future Challenges: A Review, Hüseyi̇n Avci, Fatma Doğan Güzel, Sali̇m Erol, Ali̇ Akpek

Turkish Journal of Chemistry

The significant development in the construction of microscale cell culture platforms and the interest in bioanalytical analysis have recently resulted in the emergence of a new concept of `organ-on-a-chip' systems. Organ-on-a-chip is a new three-dimensional (3D) in vitro microfabricated unit that contains a multichannel microfluidic cell culture. Even if many informative and useful data are obtained from animal models and in vitro assays, they are still limited for extrapolation to human systems during drug design and development. Only about 1 out of 10,000 compounds is processed in clinical trials for final approval. As being the first example of its kind, …


Enhanced Electrocatalytic Activity Of Copper Phthalocyanine/Multiwalled Carbon Nanotube Composite Electrode Via Pt Nanoparticle Modification For Oxygen Reduction, Çağri Ceylan Koçak, Zekerya Dursun Jan 2018

Enhanced Electrocatalytic Activity Of Copper Phthalocyanine/Multiwalled Carbon Nanotube Composite Electrode Via Pt Nanoparticle Modification For Oxygen Reduction, Çağri Ceylan Koçak, Zekerya Dursun

Turkish Journal of Chemistry

Enhanced electrocatalytic reduction of oxygen is achieved using Pt nanoparticle-modified copper phthalocya- nine-multiwalled carbon nanotube (PtNPs/CuPc-CNT) composite film on a glassy carbon electrode (PtNPs/CuPc-CNT/GCE). The PtNPs/CuPc-CNT/GCE surface is characterized by scanning electron microscopy, transmission electron microscopy, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The electrocatalytic activity of composite electrodes in the oxygen reduction reaction is investigated by cyclic voltammetry and rotating-disk electrode measurements. PtNPs/CuPc-CNT/GCE show higher catalytic activity than CNT/GCE, CuPc/GCE, and CuPc-CNT/GCE in oxygen reduction with four electron transfers.


Schiff Base Of Isoniazid And Ketoprofen: Synthesis, X-Ray Crystallographic, Spectroscopic, Antioxidant, And Computational Studies, Naima Rehman, Muhammad Khalid, Moazzam Hussain Bhatti, Uzma Yunus, Ataualpa Albert Carmo Braga, Faiz Ahmed, Syed Muddassir Ali Mashhadi, Muhammad Nawaz Tahir Jan 2018

Schiff Base Of Isoniazid And Ketoprofen: Synthesis, X-Ray Crystallographic, Spectroscopic, Antioxidant, And Computational Studies, Naima Rehman, Muhammad Khalid, Moazzam Hussain Bhatti, Uzma Yunus, Ataualpa Albert Carmo Braga, Faiz Ahmed, Syed Muddassir Ali Mashhadi, Muhammad Nawaz Tahir

Turkish Journal of Chemistry

Ketoprofen and isoniazid together are a potential combination of a nonsteroidal antiinflammatory drug and an antitubercular medicine to treat tuberculosis and associated symptoms like fever and fatigue. The Schiff base of isoniazid with ketoprofen is synthesized in this research. Infrared spectroscopy (IR) and X-ray diffraction (XRD) analysis of the crystal packing proved the formation of the Schiff base and the existence of N-H$\cdot \cdot \cdot $O hydrogen bonds between the hydrogen-bonded dimer of the Schiff base. The complete geometrical optimization of the monomer and hydrogen-bonded dimer of the Schiff base is performed utilizing M06-2X/6-31G(d,p) level theory and compared with the …


$S$-Substituted Derivatives Of 1,2,4-Triazol-3-Thiol As New Drug Candidates For Type Ii Diabetes, Aziz Ur Rehman, Khadija Nafeesa, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Syed Adnan Ali Shah, Muhammad Ashraf, Muhammad Arif Lodhi, Farman Ali Khan, Bakht Jahan Jan 2018

$S$-Substituted Derivatives Of 1,2,4-Triazol-3-Thiol As New Drug Candidates For Type Ii Diabetes, Aziz Ur Rehman, Khadija Nafeesa, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Syed Adnan Ali Shah, Muhammad Ashraf, Muhammad Arif Lodhi, Farman Ali Khan, Bakht Jahan

Turkish Journal of Chemistry

The therapeutic applications of 1,2,4-triazoles motivated us to synthesize some new derivatives. Two series of $S$-substituted derivatives (8a-8j, 12a-12i) of 5-$\{$1-[(4-chlorophenyl)sulfonyl]-3-piperidinyl$\}$-4-phenyl-4$H$-1,2,4-triazol-3-thiol (6) have been synthesized and evaluated for their biological potential. Using 4-chlorobenzene sulfonyl chloride (1) and ethyl piperidine-3-carboxylate (2), ethyl 1-[(4-chlorophenyl)sulfonyl]piperidine-3-carboxylate (3) was synthesized and converted into 3,4,5-trisubstituted 1,2,4-triazole (6) through formation of the corresponding carbohydrazide (4) and hydrazinecarbothioamide (5). Compound 6 was transformed into 8a-8j by alkyl halides (7a-7j) and into 12a-12i by $N$-aralkyl/aryl-2-bromoacetamides (11a-11i) in an aprotic solvent. The electrophiles, 11a-11i, were synthesized by gearing up $N$-substituted aralkyl/aryl amines (10a-10i) with 2-bromoacetyl bromide (9) under dynamic pH …


Highly Efficient Catalytic Degradation Of Low-Density Polyethyleneusing A Novel Tungstophosphoric Acid/Kaolin Clay Composite Catalyst, Saira Attique, Madeeha Batool, Muhammad Irfan Jalees, Khurram Shehzad, Umar Farooq, Zakir Khan, Fawad Ashraf, Asma Tufail Shah Jan 2018

Highly Efficient Catalytic Degradation Of Low-Density Polyethyleneusing A Novel Tungstophosphoric Acid/Kaolin Clay Composite Catalyst, Saira Attique, Madeeha Batool, Muhammad Irfan Jalees, Khurram Shehzad, Umar Farooq, Zakir Khan, Fawad Ashraf, Asma Tufail Shah

Turkish Journal of Chemistry

In order to take advantage of the Bronsted acidity of tungstophosphoric acid (TPA) and Lewis acidity of kaolin, TPA-loaded kaolin catalysts with varying percentages of TPA (10-50 wt.-%) were prepared by wet impregnation method. Fourier transform infrared spectrometer, X-ray diffractometer, Brunauer-Emmett-Teller surface area analyzer, and scanning electron microscope characterizations were performed to confirm the successful loading of TPA on kaolin. Catalytic cracking of low-density polyethylene (LDPE), by employing TPA-loaded kaolin as the catalyst, produced a higher percentage of fuel oil (liquid and gaseous hydrocarbons) with a negligible amount of semisolid wax (1.0 wt.-%). The wax amount was significantly lower compared …


Photocatalytic Degradation Of The Herbicide Quinclorac In Water Using Mn (Iii) Salen And Solar Light, Yisi Yang, Yan Zhang, Qingru Zeng Jan 2018

Photocatalytic Degradation Of The Herbicide Quinclorac In Water Using Mn (Iii) Salen And Solar Light, Yisi Yang, Yan Zhang, Qingru Zeng

Turkish Journal of Chemistry

Quinclorac (QNC) is a widely used herbicide and is persistent in surface and ground waters. Its residuals and converted products are hazardous to aquatic animals, vegetation, and microbes, and it is therefore important to degrade QNC using an efficient and environmental friendly technology. In this study, the photocatalytical degradation of QNC using [(R,R)-(N,N$'$-bis(3,5,3$'$,5$'$-tetra-tert-butylsalicylidene)-1,2-cyclohexanediaminato] manganese(III) acetate (Mn (III) salen) and H$_{2}$O$_{2}$ was performed under natural sunlight irradiation and a 91% degradation rate was achieved in neutral pure water in 240 min. The identified degradation products confirmed that the cleavage of QNC molecules was the main process involved in the hydroxylation, along …


Synthesis And Characterization Of Novel Unsymmetrical Phthalocyanine/Tio$_{2}$ Composites And Their Evaluation As Photocatalysts For Degradation Of 4-Chlorophenol Under Visible Light, Yunus Alp Sütcüler, Görkem Gezek, Yaghub Mahmi̇ani̇, Altuğ Mert Sevi̇m Jan 2018

Synthesis And Characterization Of Novel Unsymmetrical Phthalocyanine/Tio$_{2}$ Composites And Their Evaluation As Photocatalysts For Degradation Of 4-Chlorophenol Under Visible Light, Yunus Alp Sütcüler, Görkem Gezek, Yaghub Mahmi̇ani̇, Altuğ Mert Sevi̇m

Turkish Journal of Chemistry

We prepared novel unsymmetrical A$_{3}$B-type zinc and cobalt phthalocyanines bearing monocarboxylic acid groups on peripheral positions using statistical condensation method, especially designed to anchor on the TiO$_{2}$ semiconductor surface. The novel complexes were anchored on TiO$_{2}$ semiconductor to prepare effective dye sensitized photoactive composites as heterogeneous catalysts. The results indicated that modified TiO$_{2}$ nanocrystals possessed only the anatase phase and MPc-TiO$_{2}$ photocatalysts with loading amount of dye ca. 8.27 $\mu $mol/g TiO$_{2}$ exhibit strong visible light absorption. Photocatalytic degradation of 4-chlorophenol (4-CP) under illumination with visible light ($\lambda >$ 400 nm) was tested with the composites prepared. The degradation profile …


One-Pot Synthesis Of Substituted 4$H$-Chromenes By Nickel Ferrite Nanoparticles As An Efficient And Magnetically Reusable Catalyst, Hamideh Ahankar, Ali Ramazani, Katararzyna Slepokura, Tadeusz Lis, Sang Woo Joo Jan 2018

One-Pot Synthesis Of Substituted 4$H$-Chromenes By Nickel Ferrite Nanoparticles As An Efficient And Magnetically Reusable Catalyst, Hamideh Ahankar, Ali Ramazani, Katararzyna Slepokura, Tadeusz Lis, Sang Woo Joo

Turkish Journal of Chemistry

Nickel ferrite magnetic nanoparticles (NiFe$_{2}$O$_{4}$ MNPs) were prepared via the autocombustion assisted sol-gel method. The efficient catalyst was investigated by FT-IR, XRD, ICP, SEM, and TEM techniques. A one-pot, three-component reaction is reported for the synthesis of substituted 4$H$-chromenes in the presence of NiFe$_{2}$O$_{4}$ MNPs as a reusable catalyst in a green solvent at 40 $^{\circ}$C under clean, efficient, and mild conditions. Furthermore, selected products were characterized by FT-IR, $^{1}$H NMR, and $^{13}$C NMR. The single-crystal X-ray analysis of product 4u was also conclusively confirmed. Easy workup procedure, high purity of products via simple recrystallization, and environmentally benign conditions are …


Environmental Impact Assessment Of Natural Radioactivity And Heavy Metals In Drinking Water Around Akkuyu Nuclear Power Plant In Mersin Province, Gürsel Karahan, Hali̇m Taşkin, Nesli̇ Bi̇ngöldağ, Eni̇s Kapdan, Yusuf Zi̇ya Yilmaz Jan 2018

Environmental Impact Assessment Of Natural Radioactivity And Heavy Metals In Drinking Water Around Akkuyu Nuclear Power Plant In Mersin Province, Gürsel Karahan, Hali̇m Taşkin, Nesli̇ Bi̇ngöldağ, Eni̇s Kapdan, Yusuf Zi̇ya Yilmaz

Turkish Journal of Chemistry

The aim of this study was to determine natural radioactive and heavy element concentrations in Mersin drinking water samples before the commissioning of the Akkuyu nuclear power plant and to collect data for possible environmental contaminations in the future. Drinking water samples were taken from the provincial center, districts, and populated villages. The annual effective dose of natural radionuclides and cancer risks were calculated for each person living in the city. Hazard index and cancer risk were calculated, which were caused by heavy elements. Mean gross alpha and beta radioactivity concentrations in drinking water were 0.059 Bq/L and 0.120 Bq/L, …


Optimizing The Coagulation/Flocculation Process For Bentonite Suspension With Poly(Acrylamide-Co-(N-Methyl-4-Vinylpyridinium Tosylate, Brahim Bouras, Tayeb Hocine, Kamel Ismet Benabadji, Karim Benhabib, Ali Mansri Jan 2018

Optimizing The Coagulation/Flocculation Process For Bentonite Suspension With Poly(Acrylamide-Co-(N-Methyl-4-Vinylpyridinium Tosylate, Brahim Bouras, Tayeb Hocine, Kamel Ismet Benabadji, Karim Benhabib, Ali Mansri

Turkish Journal of Chemistry

In this work, we are interested in the quaternization of poly(acrylamide-co-4-vinylpyridine) [AM7/VP10/0.1%/] by the methyl-tosylate CH$_{3}$TS. The obtained copolymer poly(acrylamide-co-(N-methyl-4-vinylpyridinium tosylate)) [AM7/VP10/0.1%/CTs] has been characterized by $^{1}$H NMR and UV-Vis spectroscopy. The macromolecular weight was determined by size exclusion chromatography as well as by viscosity. With the aim of removing turbidity by coagulation-flocculation from bentonite suspensions, the prepared copolymer was used as a flocculant. Several important parameters in the flocculation process, such as pH of water, initial turbidity, and flocculant concentration, were utilized for the optimization of wastewater treatment. Flocculation experiments were carried out in a conventional jar test where …


Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh Jan 2018

Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh

Turkish Journal of Chemistry

Superhydrophobic nanocomposite coatings for magnesium surfaces with remarkable corrosion resistance were fabricated by electrospinning in the presence of fluorosilane-functionalized silica (SiO$_{2})$ nanoparticles. The effects of surface-modified silica (mod-SiO$_{2})$ nanoparticles on the superhydrophobicity and corrosion resistance of polystyrene (PS)/mod-SiO$_{2}$ fiber coatings were evaluated. The incorporation of the SiO$_{2}$ nanoparticles endows PS fibers with rough surfaces exhibiting a water contact angle (WCA) of 165$^{\circ}$. The surface wettability, corrosion resistance, and their relation to the inorganic content in the PS fibers and the contact angle of the composite coatings were explored. Analysis of the corrosion results confirmed that the PS/mod-SiO$_{2}$ coating protected the …


Synthesis Of Some Ketones Via Nano-Nickel Oxide Catalyzed Acylation Of Arylzinc Reagents; Strategy Involving The Use Of Mixed (Methyl)(Aryl)Zincs, Özgen Ömür Pekel, Ender Erdi̇k, Meli̇ke Kalkan Jan 2018

Synthesis Of Some Ketones Via Nano-Nickel Oxide Catalyzed Acylation Of Arylzinc Reagents; Strategy Involving The Use Of Mixed (Methyl)(Aryl)Zincs, Özgen Ömür Pekel, Ender Erdi̇k, Meli̇ke Kalkan

Turkish Journal of Chemistry

Nano-NiO catalyzed acylation of mixed (methyl)(aryl)zincs with aromatic acyl halides in THF at room temperature provides a new facile route for aryl-aroyl coupling. Among NiCl$_{2}$.L$_{2}$ and NiCl$_{2}$.L (L = monodentate and bidentate phosphine ligand) catalysts, the lower catalyst loading of NiCl$_{2}$ (dppf) may seem attractive; however, nano-NiO, being the lowest cost catalyst, is more favorable for aroylation of (methyl)(aryl)zincs. This procedure also provides a supplement to Cu and Pd catalyzed acylation of diorganozincs.


Synthesis And Characterizations Of Novel Thiazolyl-Thiadiazole Derivatives As Telomerase Activators, İsmai̇l Kayaği̇l, Ayşe Gül Mutlu, Ülkü Bayhan, İnanç Yilmaz, Şeref Demi̇rayak Jan 2018

Synthesis And Characterizations Of Novel Thiazolyl-Thiadiazole Derivatives As Telomerase Activators, İsmai̇l Kayaği̇l, Ayşe Gül Mutlu, Ülkü Bayhan, İnanç Yilmaz, Şeref Demi̇rayak

Turkish Journal of Chemistry

Pyridine-3/4-thiocarboxamide derivatives were used as starting materials for the synthesis of the target compounds. The pyridine-3/4-thiocarboxamide derivatives were reacted with ethyl 2-chloroacetoacetate in ethanol to give the thiazole derivatives (1, 2). The two ethyl thiazole-carboxylate derivatives (1, 2) thus obtained were treated with sodium hydroxide solution and ethanol and converted to carboxylic acids (3, 4). The carboxylic acid derivatives (3, 4) were reacted with thiosemicarbazide in phosphoroxy trichloride and aminothiadiazole rings (5, 6) were formed. Thus, two thiazolyl-thiadiazole amine derivatives (5, 6) were obtained. These two derivatives (5, 6) were converted into two chloroacetamidothiadiazole derivatives (7, 8) by reaction with …


Electrochemical Behavior And Voltammetric Determination Of Some Nitro-Substituted Benzamide Compounds, Özlem Sağlam, Ferah Cömert Önder, Tuğba Güngör, Mehmet Ay, Yusuf Di̇lgi̇n Jan 2018

Electrochemical Behavior And Voltammetric Determination Of Some Nitro-Substituted Benzamide Compounds, Özlem Sağlam, Ferah Cömert Önder, Tuğba Güngör, Mehmet Ay, Yusuf Di̇lgi̇n

Turkish Journal of Chemistry

Voltammetric behaviors of six nitro-substituted benzamides, which are potential prodrug candidates for nitroreductase-based cancer therapy, were investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The electrochemical behavior of aromatic nitro (ArNO$_{2})$ compounds by CV indicates that compounds involve various reduction/oxidation steps including the formation of aromatic nitro radical, nitroso, hydroxylamine, and amine groups. Applicability of the voltammetric determination of these prodrug candidates was studied by recording their DPVs, carried out in mixed media (Britton Robinson buffer solution $+$ DMF) at various pH values on a pencil graphite electrode (PGE). Results show that the PGE can offer a disposable, …


A Simple Automated Microplate Method For Determining Reducing Sugars In Food Extracts And Synthetic Serum Using Cupric-Neocuproine As Reductant, Mustafa Bener, Esi̇n Akyüz, Furkan Burak Şen, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak Jan 2018

A Simple Automated Microplate Method For Determining Reducing Sugars In Food Extracts And Synthetic Serum Using Cupric-Neocuproine As Reductant, Mustafa Bener, Esi̇n Akyüz, Furkan Burak Şen, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak

Turkish Journal of Chemistry

In the present work, a simple automated microplate method based on cupric ion reduction is described for determining total reducing sugars in food extracts and synthetic serum. The reaction of Cu(II)-Nc (cupric-neocuproine) with reducing sugars was performed in alkaline medium in microplates, and the absorbance of the formed highly colored Cu(I)-Nc chelate in a plate reader at 450 nm was recorded. The proposed method was applied to reducing sugars (glucose, fructose, galactose, maltose, and lactose) and their linear calibration curves were constructed. The detection and quantification limits (LOD and LOQ) for glucose were 0.14 and 0.46 $\mu $M, respectively. Absorbances …


An Ionic Liquid/Bismuth Film-Modified Sensor For The Electrochemical Detection Of Cefixime, Yeşi̇m Tuğçe Yaman, Gülçi̇n Bolat, Ceren Yardimci, Serdar Abaci Jan 2018

An Ionic Liquid/Bismuth Film-Modified Sensor For The Electrochemical Detection Of Cefixime, Yeşi̇m Tuğçe Yaman, Gülçi̇n Bolat, Ceren Yardimci, Serdar Abaci

Turkish Journal of Chemistry

A highly sensitive and simple method based on an ionic liquid/ex situ bismuth film-modified single-use pencil graphite electrode (IL/Bi/PGE) was offered for the electrochemical detection of cefixime (CEF) for the first time. The synergistic effects of the ionic liquid and bismuth film combination as the surface modifier remarkably improved the electrochemical response of the modified sensor. Anodic oxidation of CEF was observed at 0.9 V vs. Ag/AgCl/3 M KCl as one well-defined irreversible oxidation peak. Under optimum experimental conditions, the IL/Bi/PGE exhibited a linear relationship for CEF concentrations in the range of 0.005--0.5 $\mu $M (R$^{2}$ = 0.996) with a …


Synthesis And Evaluation Of Novel 1,3,4-Thiadiazole--Fluoroquinolone Hybrids As Antibacterial, Antituberculosis, And Anticancer Agents, Asli Demi̇rci̇, Kaan Gökçe Karayel, Esra Tatar, Si̇nem Öktem Okullu, Ni̇han Ünübol, Paki̇ze Nesli̇han Taşli, Zühtü Tanil Kocagöz, Fi̇kretti̇n Şahi̇n, İlkay Küçükgüzel Jan 2018

Synthesis And Evaluation Of Novel 1,3,4-Thiadiazole--Fluoroquinolone Hybrids As Antibacterial, Antituberculosis, And Anticancer Agents, Asli Demi̇rci̇, Kaan Gökçe Karayel, Esra Tatar, Si̇nem Öktem Okullu, Ni̇han Ünübol, Paki̇ze Nesli̇han Taşli, Zühtü Tanil Kocagöz, Fi̇kretti̇n Şahi̇n, İlkay Küçükgüzel

Turkish Journal of Chemistry

A series of 5-substituted-1,3,4-thiadiazole-based fluoroquinolone derivatives were designed as potential antibacterial and anticancer agents using a molecular hybridization approach. The target compounds 16-25 were synthesized by reacting the corresponding $N$-(5-substituted-1,3,4-thiadiazol-2-yl)-2-chloroacetamides with ciprofloxacin or norfloxacin. The purity and identity of the synthesized compounds were determined by the use of chromatographic and spectral techniques (NMR, IR, MS, etc.) besides elemental analysis. Antibacterial, antituberculosis, and anticancer activity of the target compounds were evaluated against selected strains and cancer cell lines. Compound 20 was appreciated as the most active agent representing antibacterial activity against Escherichia coli and Staphylococcus aureus with MIC values of 4 …


The First Synthesis And Antioxidant And Anticholinergic Activities Of 1-(4,5-Dihydroxybenzyl)Pyrrolidin-2-One Derivative Bromophenols Including Natural Products, Mohsen Rezai̇, Çeti̇n Bayrak, Parham Tasli̇mi̇, İlhami̇ Gülçi̇n, Abdullah Menzek Jan 2018

The First Synthesis And Antioxidant And Anticholinergic Activities Of 1-(4,5-Dihydroxybenzyl)Pyrrolidin-2-One Derivative Bromophenols Including Natural Products, Mohsen Rezai̇, Çeti̇n Bayrak, Parham Tasli̇mi̇, İlhami̇ Gülçi̇n, Abdullah Menzek

Turkish Journal of Chemistry

We report herein the first synthesis of biologically active natural bromophenols, namely 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)pyrrolidin-2-one (2), 2RS-1-(2,3-dibromo-4,5-dihydroxybenzyl)-5-oxopyrrolidine-2-carboxylic acid (3), and 2RS-methyl 1-(2,3-dibromo-4,5-dihydroxybenzyl)-5-oxopyrrolidine-2-carboxylate (4), along with their different derivatives (6 and 8-18). Among the synthesized compounds, , 4, and their derivatives (8 and 9) are yielded in racemic form. Radical scavenging assays of the synthesized molecules were investigated using various bioanalytical antioxidant methods including 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS$^{\bullet +})$ and 2,2-diphenyl-1-picrylhydrazyl (DPPH$^{\bullet })$. In addition, the reducing power of the novel bromophenols was investigated by Cu$^{2+}$-Cu$^{+}$ reducing, Fe$^{3+}$-Fe$^{2+}$ reducing, and [Fe$^{3+}$-(TPTZ)$_{2}$]$^{3+}$-[Fe$^{2+}$-(TPTZ)$_{2}$]$^{2+}$ reducing capacity and ferrous ions (Fe$^{2+})$ chelating abilities. The molecules demonstrated powerful …


Computational Investigation Of Intramolecular Reorganization Energy In Diketopyrrolopyrrole (Dpp) Derivatives, Şule Atahan Evrenk Jan 2018

Computational Investigation Of Intramolecular Reorganization Energy In Diketopyrrolopyrrole (Dpp) Derivatives, Şule Atahan Evrenk

Turkish Journal of Chemistry

Intramolecular reorganization energy (RE) of molecules derived from the diketopyrrolopyrrole (DPP) unit has been studied using B3LYP/6-31G(d,p) theory. It was found that the replacement of the oxygen atoms with sulfur in the DPP unit led to a smaller RE for both the hole and electron transfer processes. One disadvantage of the sulfur replacement is the twist of the conjugated backbone, which might impair the $\pi - \pi $ interactions in the solid state. The RE calculated from the adiabatic potential energy surfaces and that derived from the normal mode analysis agreed well for both systems. Electronic structure data showed that …


Efficient Reductive Claisen Rearrangement Of Prop-2'-Enyloxyanthraquinones And 2'-Chloroprop-2'-Enyloxyanthraquinones With Iron Powder In Ionic Liquids, Samaneh Nadali, Ali Khoshroo, Ghasem Aghapour Jan 2018

Efficient Reductive Claisen Rearrangement Of Prop-2'-Enyloxyanthraquinones And 2'-Chloroprop-2'-Enyloxyanthraquinones With Iron Powder In Ionic Liquids, Samaneh Nadali, Ali Khoshroo, Ghasem Aghapour

Turkish Journal of Chemistry

A rapid and selective iron-mediated reductive Claisen rearrangement of various prop-2'-enyloxyanthraquinones and 2'-chloroprop-2'-enyloxyanthraquinones to 1-hydroxy-2-(prop-2'-enyl)anthraquinones and anthrafurandiones is presented. All reactions are carried out in a mixture of ionic liquids, [Bzmim]Cl (1-benzyl-3-methylimidazolium chloride) and [Hmim]BF$_{4}$ (1-methylimidazolium tetrafluoroborate), in short reaction times (5-35 min). Our study showed that 1-(prop-2'-enyloxy)anthraquinone is more active than 1-(2'-chloroprop-2'-enyloxy)anthraquinone to perform this rearrangement.


Synthesis, Solvatochromism, And Biological Activity Of Novel Azo Dyes Bearing 2-Pyridone And Benzimidazole Moieties, Dusan Mijin, Biljana Bozic Nedeljkovic, Bojan Bozic, Ilijana Kovrlija, Jelena Ladarevic, Gordana Uscumlic Jan 2018

Synthesis, Solvatochromism, And Biological Activity Of Novel Azo Dyes Bearing 2-Pyridone And Benzimidazole Moieties, Dusan Mijin, Biljana Bozic Nedeljkovic, Bojan Bozic, Ilijana Kovrlija, Jelena Ladarevic, Gordana Uscumlic

Turkish Journal of Chemistry

New azo dyes bearing 2-pyridone and benzimidazole moieties were prepared using diazotization of 4-(1H-benzo[d]imidazol-2-yl)aniline and coupling of the obtained diazonium salt with substituted 3-cyano-2-pyridones. Obtained compounds were characterized via UV-Vis, FT-IR, and $^{1}$H and $^{13}$C NMR spectroscopy as well as by elemental analysis data. The UV-Vis spectra of the synthesized dyes were measured in thirteen solvents of different properties at room temperature. Solvatochromism and tautomerism of novel azo dyes were discussed. An MTT (3,4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide) test was performed to prove the biocompatibility of the investigated dyes. The investigated dyes exhibited satisfying antiproliferative activities against both tumor cell lines, MDA-MB-231 …


One-Pot Multicomponent Synthesis Of Piperidinium 3,3'-(Arylmethylene) Bis (2-Hydroxynaphthalene-1,4-Diones): Nmr Spectroscopic And X-Ray~Structure Characterization, Maryam Fatahpour, Nourollah Hazeri, Malek Taher Maghsoodlou, Fatemeh Noori Sadeh, Mojtaba Lshkari Jan 2018

One-Pot Multicomponent Synthesis Of Piperidinium 3,3'-(Arylmethylene) Bis (2-Hydroxynaphthalene-1,4-Diones): Nmr Spectroscopic And X-Ray~Structure Characterization, Maryam Fatahpour, Nourollah Hazeri, Malek Taher Maghsoodlou, Fatemeh Noori Sadeh, Mojtaba Lshkari

Turkish Journal of Chemistry

A facile synthesis of piperidinium 3,3'-(arylmethylene) bis (2-hydroxynaphthalene-1,4-dione) analogs as organic salts is described by the one-pot pseudo-four-component reaction between 2-hydroxy-1,4-naphthoquinone, aromatic aldehydes, and piperidine. The single-crystal X-ray diffraction analysis of these systems confirms that the stabilized predominant interactions are N-H\... O and O-H\... O hydrogen bonds. Mild and clean reaction conditions, high atom economy, and operational simplicity of this one-pot multicomponent reaction coupled with excellent yields and no need for column chromatography have transformed this procedure to be a superior synthetic route for the efficient formation of families of naphthoquinone-derived compounds.


Removal Of Toxic Metals From Canola Oil By Newly Synthesized Calixarene-Based Resin, Muhammad Afzal Kamboh, Shahabuddi̇n Memon, Liaquat Ali Zardari, Hamid Rashidi Nodeh, Syed Tufail Hussain Sherazi, Mustafa Yilmaz Jan 2018

Removal Of Toxic Metals From Canola Oil By Newly Synthesized Calixarene-Based Resin, Muhammad Afzal Kamboh, Shahabuddi̇n Memon, Liaquat Ali Zardari, Hamid Rashidi Nodeh, Syed Tufail Hussain Sherazi, Mustafa Yilmaz

Turkish Journal of Chemistry

This study describes the synthesis, characterization, and application of a new $p-$sulfonatocalix[4]arene-based silica resin (calix-resin 5) for the extraction of selected metals, namely Pb, Cd, Co, Ni, Cu and Fe, from canola oil. Synthesis, morphology, purity, and elemental composition of calix-resin 5 were analyzed by FT-IR spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy. The metal extraction efficiency of calix-resin 5 was evaluated through the batch-wise method with a flame and graphite furnace atomic absorption spectrometer following the wet acid digestion procedure. The results obtained showed that the newly fabricated adsorbent material calix-resin 5 is an efficient adsorbent and exhibits great …


Synthesis Of Novel Sn38-Aspirin Prodrugs For The Treatment Of Hepatocellular Carcinoma, Zhimin Chen, Yi Luo, Aiping Fang, Chen Fan, Chenjuan Zeng Jan 2018

Synthesis Of Novel Sn38-Aspirin Prodrugs For The Treatment Of Hepatocellular Carcinoma, Zhimin Chen, Yi Luo, Aiping Fang, Chen Fan, Chenjuan Zeng

Turkish Journal of Chemistry

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is a leading cause of cancer-related death worldwide. However, there is no effective chemotherapeutic treatment for HCC and its prognosis remains poor. Consequently, it is urgent to find an efficient antitumor agent to treat HCC. In this study, 7-ethyl-10-hydroxycamptothecin (SN38), the bioactive metabolite of the anticancer drug irinotecan (CPT-11), which is 100-1000 times more potent than CPT-11, was coupled with aspirin to give 4 prodrugs. Their structures were characterized by $^{1}$H~NMR and elemental analysis. The in vitro anticancer activities of these compounds on two human hepatocellular carcinoma cell lines …


Analysis Of Electrochemical Noise In Nicd Batteries Throughout Their Lifetime, Burak Ülgüt Jan 2018

Analysis Of Electrochemical Noise In Nicd Batteries Throughout Their Lifetime, Burak Ülgüt

Turkish Journal of Chemistry

Electrochemical noise measurements have been applied to electrochemical systems that show stochastic behavior. The standard area of study that benefits from this stochastic analysis is localized corrosion modes like pitting and crevice corrosion. Application of electrochemical noise measurements to battery systems, though rare, is recently becoming more popular. The present contribution first establishes a method of analyzing electrochemical voltage noise data for NiCd batteries, then follows four samples of batteries in terms of voltage noise throughout their lifetimes. The noises exhibited by battery systems are small, but finite. This noise is expected to be due to variations in the electrochemistry …