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Full-Text Articles in Physical Sciences and Mathematics

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 …


Facile Synthesis Of Iro$_{2}$ Nanoclusters And Their Application As Catalysts In The Degradation Of Azo Dyes, Rajni Lasyal, Anjali Goel Jan 2018

Facile Synthesis Of Iro$_{2}$ Nanoclusters And Their Application As Catalysts In The Degradation Of Azo Dyes, Rajni Lasyal, Anjali Goel

Turkish Journal of Chemistry

A robust synthesis of iridium oxide (IrO$_{2})$ nanoclusters using methanol as a reducing agent via the chemical reduction method is reported in this article. Polyvinylpyrrolidone (PVP) and polyoxyethylene(23) lauryl ether (POLE) were used as stabilizers. The formation of IrO$_{2}$ nanoclusters was confirmed by the appearance of new absorption peak at 230 nm in UV-vis spectra. XRD and TEM were used to determine the degree of crystallinity and size of nanoclusters, respectively. Further characterization studies were carried out by FT-IR spectroscopy to investigate the coordination between IrO$_{2}$ nanoclusters and stabilizers. The size of the nanoclusters was found to be a factor …


One-Step Potentiostatic Codeposition And Electrochemical Studies Of Poly(1-Pyrenyl)-2,5-Di(2-Thienyl)Pyrrole-Co-Pyrrole) Film For Electrochemical Supercapacitors, Hakan Görçay, İlhami̇ Çeli̇k, Yücel Şahi̇n Jan 2018

One-Step Potentiostatic Codeposition And Electrochemical Studies Of Poly(1-Pyrenyl)-2,5-Di(2-Thienyl)Pyrrole-Co-Pyrrole) Film For Electrochemical Supercapacitors, Hakan Görçay, İlhami̇ Çeli̇k, Yücel Şahi̇n

Turkish Journal of Chemistry

In this paper, we report a simple, low-cost, and environmentally friendly electrochemical method to obtain a novel copolymer consisting of 1-pyrenyl-2,5-di(2-thienyl)pyrrole and pyrrole on a pencil graphite electrode (PGE). Poly(1-pyrenyl)-2,5-di(2-thienyl)pyrrole-co-pyrrole) that is P(PyrPy-co-Py) film was prepared by one-step potentiostatic codeposition in an ethanol solution containing PyrPy and Py monomers for supercapacitor applications. The electrodeposition of homopolymer and copolymer modified electrodes was carried out on the surface of the PGE via chronocoulometry. For comparison, P(Py)/PGE and P(PyrPy)/PGE were also electrochemically synthesized under the same reaction conditions. The surface morphologies of all the electrode materials were analyzed by field emission scanning electron …


New Triplet Silylenes M-Si-M$'$--X Along With Some Unusual Cyclic Forms (M = Li, Na, And K; M$'$ = Be, Mg, And Ca; X = F, Cl, And Br), Samaneh Ashenagar, Mohamad Zaman Kassaee Jan 2018

New Triplet Silylenes M-Si-M$'$--X Along With Some Unusual Cyclic Forms (M = Li, Na, And K; M$'$ = Be, Mg, And Ca; X = F, Cl, And Br), Samaneh Ashenagar, Mohamad Zaman Kassaee

Turkish Journal of Chemistry

Comparison of 54 M-Si--M$'$-X species is carried out using quantum mechanical ab initio and DFT computations at B3LYP/6-311$++$G**, QCISD(T)/6-311$++$G**, and CCSD(T)/6-311$++$G** levels of theory (M = Li, Na, K; M$'$ = Be, Mg, Ca, and X = F, Cl, Br). All triplet species with M = K appear more linear than their corresponding ones with Li and Na. The electronegativity reactivity descriptor for each halogen (X = F, Cl, Br) is used as a tool to evaluate the interrelated properties of these silylenes. Stability, assumed as singlet-triplet energy difference ($\Delta E_{S-T})$ for each series depends on the substituent's electropositivity, analyzed …


Voltammetric Determination Of Phenmedipham Herbicide Using A Multiwalled Carbon Nanotube Paste Electrode, Ersi̇n Demi̇r, Recai̇ İnam Jan 2018

Voltammetric Determination Of Phenmedipham Herbicide Using A Multiwalled Carbon Nanotube Paste Electrode, Ersi̇n Demi̇r, Recai̇ İnam

Turkish Journal of Chemistry

Phenmedipham is an herbicide used especially in the sugar beet harvest to fight against broad-leaved weeds and studies of its voltammetric behavior and detection have not been done before. The superior properties of carbon nanotubes such as electrical conductivity, mechanical strength, and wide potential ranges make them attractive for chemical sensors and the phenmedipham compound gave an oxidation peak at $+$1320 mV (vs. Ag/AgCl) on the nanostructured multiwalled carbon nanotube paste electrode. Square wave voltammetric measurements recorded for phenmedipham showed that the peak current increased linearly between 0.02 and 2.0 mg/L with a regression coefficient of $r$ = 0.9989, and …


A Novel One-Pot And Rapid Synthesis Of Polyfunctionalized Benzo[A]Pyrimido[5',4':5,6] Pyrido[2,3-C]Phenazine Derivatives Under Microwave Irradiation, Mahdieh Tabibian, Razieh Mohebat, Masoumeh Tabatabaee Jan 2018

A Novel One-Pot And Rapid Synthesis Of Polyfunctionalized Benzo[A]Pyrimido[5',4':5,6] Pyrido[2,3-C]Phenazine Derivatives Under Microwave Irradiation, Mahdieh Tabibian, Razieh Mohebat, Masoumeh Tabatabaee

Turkish Journal of Chemistry

A one-pot, environmentally friendly, and efficient protocol for the synthesis of novel polyfunctionalized benzo[$a$]pyrimido[5',4':5,6]pyrido[2,3-$c$]phenazine derivatives has been reported by a one-pot, four-component sequential reaction between 2-hydroxynaphthalene-1,4-dione, benzene-1,2-diamines, benzaldehydes, and 6-amino-1,3-dimethyluracil in the presence of $p$-TSA as a nontoxic, inexpensive, ecofriendly, and efficacious solid acid catalyst. Two C-C bonds, two C=N bonds, and one C-N bond, as well as two new rings, were formed in this reaction. Through this procedure, compounds with substantial biological and pharmaceutical properties are generated in a single operation. Factors such as high yields, less reaction time, operational simplicity, and lack of any dangerous reagents/solvents have made …


Solid-Phase Extraction Method For Preconcentration Of Cadmium And Lead In Environmental Samples Using Multiwalled Carbon Nanotubes, Ayman A. Gouda, Wael A. Zordok Jan 2018

Solid-Phase Extraction Method For Preconcentration Of Cadmium And Lead In Environmental Samples Using Multiwalled Carbon Nanotubes, Ayman A. Gouda, Wael A. Zordok

Turkish Journal of Chemistry

A new sensitive and accurate solid-phase extraction method for preconcentration of trace amounts of cadmium and lead in various environmental samples prior to flame atomic absorption spectrometry determination has been developed. The proposed method is based on the utilization of multiwalled carbon nanotubes in combination with 5-benzyl-4-[-chlororbenzylidene amine]-4H-1,2,4-triazole-3-thiol (BCBATT) as a solid-phase sorbent with the aid of ultrasonication. The effect of the preconcentration parameters was investigated. Good recoveries ranging from 95% to 102% with relative standard deviations of 3.2% and 2.8% for Cd$^{2+}$ and Pb$^{2+}$, respectively, were obtained, indicating high accuracy and precision. The limits of detection were 0.2 and …


Ion-Pair Based Liquid-Liquid Extraction Of Gold(Iii) From Malonate Media Using 2-Octylaminopyridine As An Extractant: Analysis Of Alloys, Minerals, And Drug Samples, Vishal Suryavanshi, Arjun Kokare, Sunil Zanje, Abhijeet Mulik, Rupali Pawar, Makrand Patil, Ashwini Gaikwad, Mansing Anuse, Ganpatrao Mulik Jan 2018

Ion-Pair Based Liquid-Liquid Extraction Of Gold(Iii) From Malonate Media Using 2-Octylaminopyridine As An Extractant: Analysis Of Alloys, Minerals, And Drug Samples, Vishal Suryavanshi, Arjun Kokare, Sunil Zanje, Abhijeet Mulik, Rupali Pawar, Makrand Patil, Ashwini Gaikwad, Mansing Anuse, Ganpatrao Mulik

Turkish Journal of Chemistry

Liquid-liquid extraction of Au(III) from aqueous sodium malonate medium using 2-octylaminopyridine (2-OAP) as an extractant in xylene was achieved. The current work explored the influence of several experimental parameters such as pH, weak acid concentration, extractant concentration, equilibrium time, stripping agents, and aqueous:organic volume ratio on the extraction of Au(III). The experimental results showed that the Au(III) was quantitatively extracted to about 99.5% by 0.05 M 2-OAP in 0.05 M malonate at 5.0 pH. Ammonia solution was used to strip the gold-loaded organic phase and about 99.5% of Au(III) was reversibly extracted into the aqueous phase. Gold(III) was extracted into …


A Rapid And Sensitive Spectrofluorometric Method For The Determination Of Au(Iii) Based On Fluorescence Quenching Of A 1,3,5-Triphenyl-2-Pyrazoline, Aysel Başoğlu, Ümmühan Ocak, Seda Fandakli, Nuretti̇n Yayli Jan 2018

A Rapid And Sensitive Spectrofluorometric Method For The Determination Of Au(Iii) Based On Fluorescence Quenching Of A 1,3,5-Triphenyl-2-Pyrazoline, Aysel Başoğlu, Ümmühan Ocak, Seda Fandakli, Nuretti̇n Yayli

Turkish Journal of Chemistry

A simple, rapid, sensitive, and low-cost spectrofluorometric method was developed for the determination of Au(III) using 5-(2,3-dimethoxyphenyl)-3-(4-methoxyphenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (L) in ethanol/water. The method is based on the change in the fluorescence intensity at 464 nm after excitation at 355 nm as a result of the reaction between the ligand and Au(III). The fluorescent emission of ligand at 464 nm decreased with the increasing of Au(III) concentration. The ligand concentration, pH effect, response time, and effect of foreign ions were determined. From the results of fluorescence titration experiments, it was found that the ligand (1 $\times $ 10$^{-7}$ M) was selective and …


Development Of A Nanoscale-Based Optical Chemical Sensor For The Detection Of No Radical, Özlem Öter, Aki̇f Ci̇han Aydin, Merve Zeyrek Ongun, Erdal Çeli̇k Jan 2018

Development Of A Nanoscale-Based Optical Chemical Sensor For The Detection Of No Radical, Özlem Öter, Aki̇f Ci̇han Aydin, Merve Zeyrek Ongun, Erdal Çeli̇k

Turkish Journal of Chemistry

Nitric oxide is one of the most important biochemical parameters in biological processes; it is also known as carcinogenic. There is need for the design of stable and durable solid phase nitric oxide sensors. In this study, we immobilized the nitric oxide sensitive molecules pyrene, tris(2,2'-bipyrdyl)dichlororuthenium(II) hexahydrate (Ru(bipy)$_{3}^{2+})$, and magnesium phthalocyanine (Mg-Pc) for the first time in polymeric or glassy matrices. We applied silver nanoparticles and ionic liquids in the fabrication process of polymeric electrospun fibers and thin films. We compared their NO sensitivity in micelle solutions that mimic the cell medium by both steady state and lifetime-based fluorescence measurements. …


New $N$-4 Piperazinyl Derivatives Of Norfloxacin: Design, Synthesis, And Correlation Of Calculated Physicochemical Parameters With Antibacterial Activity, Gamal El-Din Abou Rahma, Samar Abbas, Mai Shoman, Ibtihal Samir, Rehab Abd El-Baky Jan 2018

New $N$-4 Piperazinyl Derivatives Of Norfloxacin: Design, Synthesis, And Correlation Of Calculated Physicochemical Parameters With Antibacterial Activity, Gamal El-Din Abou Rahma, Samar Abbas, Mai Shoman, Ibtihal Samir, Rehab Abd El-Baky

Turkish Journal of Chemistry

A group of $N-$4 piperazinyl derivatives of norfloxacin was synthesized and identified by different spectroscopic techniques. The $N-$4 piperazinyl substituent in target compounds 2a-2k, 3a-3c, and 4a and 4b was designed to have different electronic, steric, and physicochemical properties. The antibacterial activity of the newly synthesized compounds was evaluated against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus strains using norfloxacin as a reference. Results showed that most of the tested compounds had higher activity against E. coli and K. pneumoniae than norfloxacin, whereas only five derivatives were more active against P. aeruginosa. On the other hand, all derivatives …


The Synthesis Of New 3,4-(Bisaryl)-1,8-Naphthalimide And 2,3-(Bisaryl)-7$H$-Benzimidazo[2,1-A]Benzo[D]Isoquinolin-7-One Compounds And An Investigation Of Their Photochromic Properties, Ersi̇n Orhan, Mahmut Köse, Tolga Yazan Jan 2018

The Synthesis Of New 3,4-(Bisaryl)-1,8-Naphthalimide And 2,3-(Bisaryl)-7$H$-Benzimidazo[2,1-A]Benzo[D]Isoquinolin-7-One Compounds And An Investigation Of Their Photochromic Properties, Ersi̇n Orhan, Mahmut Köse, Tolga Yazan

Turkish Journal of Chemistry

Three new photochromic compounds, 3-(2,5-dimethyl-3-thienyl)-4-(2-phenyl-5-methyl-4-thiazolyl)-1,8-napht- halimide (1-O), 2,3-bis(2-phenyl-5-methyl-4-thiazolyl)-7$H$-benzimidazo[2,1-a]benzo[de]isoquinolin-7-one (2-O), and 2,5-dimethyl-3-thienyl)-7$H$-benzimidazo[2,1-a]benzo[de]isoquinolin-7-one (3-O), were synthesized and their photochromic properties were studied. Compound 1-O was synthesized by two consecutive Suzuki coupling reactions using 2,5-dimethylthiophene-3-boronic acid and 5-methyl-2-phenylthiazole-4-boronic acid. Photochromic compounds 2-O and 3-O were prepared by multistep reactions starting with 3-iodo-4-bromo-1,8-naphthalic anhydride and 2,5-dimethylthiophene-3-boronic acid or 2-phenyl-5-methylthiazole-4-boronic acid. All photochromic compounds showed a color change from colorless (or light yellow) to blue-green, purple, or orange colors (depending on the nature of the structures) on exposure to UV light at 365 nm in ethyl acetate solutions. The colored solutions can be reversed to …


Synthesis, Characterization, And Evaluation Of Toxicity Of Quaternary Ammonium Chlorides Of Glucose-Based Este, Anna Parus, Grzegorz Framski Jan 2018

Synthesis, Characterization, And Evaluation Of Toxicity Of Quaternary Ammonium Chlorides Of Glucose-Based Este, Anna Parus, Grzegorz Framski

Turkish Journal of Chemistry

This study presents the synthesis of glucose-based surfactants including quaternary ammonium salts. Their surface properties and influence on the soil environment were investigated. The synthesized quaternary ammonium chlorides of glucose-based ester exhibited good surface tension reduction properties and formed stable foam in contact with water. The results showed that quaternary ester ammonium salts affect the activation of metals (nickel and cadmium) from the soil matrix after their introduction into the soil environment. This phenomenon can increase the bioavailability of these metals. The introduction of glucose surfactants to the soil increased microorganism activity, which may indicate that these compounds were used …


Synthesis, Characterization, And Evaluation Of Antioxidant Activity Of New $\Gamma $- And $\Delta $-Imino Esters, Hasni̇ye Yaşa Jan 2018

Synthesis, Characterization, And Evaluation Of Antioxidant Activity Of New $\Gamma $- And $\Delta $-Imino Esters, Hasni̇ye Yaşa

Turkish Journal of Chemistry

New Schiff bases were synthesized by condensation of methyl-5-(furan-2-yl)-5-oxopentanoate, methyl-4-(furan-2-yl)-4-oxobutanoate, methyl-5-(thiophene-2-yl)-5-oxopentanoate, and methyl-4-(thiophene-2-yl)-4-oxobutanoate with $p$-anisidine and $n$-butylamine. The structures of these synthesized compounds were clarified on the basis of elemental analysis, IR, $^{1}$H NMR, $^{13}$C NMR, and GC-MS spectroscopic techniques. In addition, antioxidant activity of the synthesized compounds was evaluated on the basis of DPPH radical.


Synthesis, Molecular Docking, And Pharmacological Evaluation Of Halobenzodithiophene Derivatives Against Alpha-Glucosidase, Urease, And Free Radical Production, Ghulam Abbas, Zahid Hassan, Ahmed Al-Harrasi, Syed Aun Muhammad, Ahood Juma Al-Quraini1, Zahra Khamis Al-Maani1, Ahmed Mohammed Al-Adawai Jan 2018

Synthesis, Molecular Docking, And Pharmacological Evaluation Of Halobenzodithiophene Derivatives Against Alpha-Glucosidase, Urease, And Free Radical Production, Ghulam Abbas, Zahid Hassan, Ahmed Al-Harrasi, Syed Aun Muhammad, Ahood Juma Al-Quraini1, Zahra Khamis Al-Maani1, Ahmed Mohammed Al-Adawai

Turkish Journal of Chemistry

Benzodithiophenes are heterocyclic compounds that have various medicinal and industrial applications. In the present study, halobenzodithiophene, the simplest benzofused thiophene, and its derivatives were synthesized and evaluated against alpha-glucosidase, urease, and free radical production. In the alpha-glucosidase inhibition assay, compound 2,2-bisbenzothiophne (1) exhibited potent activity with IC$_{50}$ = 135 $\pm $ 0.51 $\mu $M, while its derivative 2,7-bis(butoxycarbonyl)-3,6-dichlorobenzo[1,2-$b$;6,5-$b$']dithiophene (2) exhibited promising inhibition with IC$_{50}$ = 263 $\pm $ 0.32 $\mu $M. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay, compound 2 exhibited promising activity with IC$_{50}$ = 33 $\pm $ 0.42 $\mu $M, while compound 1 showed moderate inhibition in the urease …


Differential Pulse Voltammetric Determination Of Dopamine Using Pd Nanoparticles Deposited On (3-Aminopropyl)Triethoxysilane Functionalized Ceo$_{2}$ Nanoparticles, Muhammet Güler Jan 2018

Differential Pulse Voltammetric Determination Of Dopamine Using Pd Nanoparticles Deposited On (3-Aminopropyl)Triethoxysilane Functionalized Ceo$_{2}$ Nanoparticles, Muhammet Güler

Turkish Journal of Chemistry

In this study, a novel and effective electrochemical sensor for determination of dopamine (DA) was successfully developed by the modification of a glassy carbon electrode (GCE) using Pd nanoparticles deposited on (3-aminopropyl)triethoxysilane functionalized nanoceria (Pd@CeO$_{2}$-APTES) and nafion used as a protective membrane. The synthesized nanocomposites were evaluated using X-ray diffraction, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy. Moreover, the electrochemical properties of the modified electrodes were investigated using cyclic voltammetry, electrochemical impedance voltammetry, and differential pulse voltammetry (DPV). The Nf/Pd@CeO$_{2}$-APTES/GCE showed a linear range of 2.5--149.5 $\mu $M for DA by DPV with a notable sensitivity of 3.89 …


The Design And Synthesis Of A Photo-Controlled, Peptide-Based Potential Drug Carrier, Melek Parlak Khali̇ly, Sali̇h Özçubukçu Jan 2018

The Design And Synthesis Of A Photo-Controlled, Peptide-Based Potential Drug Carrier, Melek Parlak Khali̇ly, Sali̇h Özçubukçu

Turkish Journal of Chemistry

Our focus in this study is on the design and synthesis of a light-responsive peptide-based nanocarrier in order to develop effective and biocompatible drug delivery systems. The synthesized nanocarrier is basically composed of peptide amphiphiles comprising a micelle forming a Pro-Pro-Pro-Lys-Lys-Lys peptide sequence with an attached anthracene fluorophore. Anthracene containing an inner core of the micelle can serve as a storage site for poorly water-soluble drugs. Moreover, anthracenes that come in close proximity with the formation of micellar structures can undergo photodimerization upon irradiation at 365 nm, which disrupts the micelle structures formed by the self-assembly of the peptide amphiphiles. …