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Full-Text Articles in Physical Sciences and Mathematics

One-Pot Synthesis Of New N-(1-Methylpyridin-4(1h)-Ylidene)Amine Ligands Forpalladium-Catalyzed Heck Coupling Reaction, Muhammad Zafar, Sabeen Zahra, Muhammad Tahir, Ehsan Mughal, Muhammad Nazar, Hummera Rafique Jan 2018

One-Pot Synthesis Of New N-(1-Methylpyridin-4(1h)-Ylidene)Amine Ligands Forpalladium-Catalyzed Heck Coupling Reaction, Muhammad Zafar, Sabeen Zahra, Muhammad Tahir, Ehsan Mughal, Muhammad Nazar, Hummera Rafique

Turkish Journal of Chemistry

A series of new derivatives of N-(1-methylpyridin-4(1H)-ylidene)amines, [L1]-[L5], were synthesized and characterized by FTIR, NMR, MS, and XRD analysis. These targeted compounds were synthesized by the melt reaction between N-methylated-4-chloropyridinium triflate and corresponding amines (1-naphthyl amine, o-ansidine, 2-nitroaniline, p-ansidine, and cyclohexyl amine) followed by the addition of sodium hydride in dichloromethane in the same pot. These highly electron-donating N-(1-methylpyridin-4(1H)-ylidene)amine ligands considerably improve the catalytic activity of palladium acetate towards Heck-Mizoroki carbon-carbon cross-coupling reactions.


Synthesis And Evaluation Of Catecholase Activities Of Metal Complexes Of 1,4-Substituted Piperazine Mannich Base Of 4-Acetamidopheno, Ayowole Olaolu Ayeni, Gareth Mostyn Watkins Jan 2018

Synthesis And Evaluation Of Catecholase Activities Of Metal Complexes Of 1,4-Substituted Piperazine Mannich Base Of 4-Acetamidopheno, Ayowole Olaolu Ayeni, Gareth Mostyn Watkins

Turkish Journal of Chemistry

The synthesis and characterisation including $^{1}$H and $^{13}$C NMR spectroscopy of a Mannich~base~1,4-di-(5-acetamido-2-hydroxybenzyl)piperazine~is herein reported. The Mannich reaction leading to the formation of the ligand took place at both ends of piperazine. Four metal complexes [Cu(II) and Fe(III)] including those bearing thiocyanate groups (SCN-) in N- and S-bonding modes have been studied for their abilities to mimic catecholase oxidase. All the metal complexes are catalytically active with the highest turnover rate (k$_{cat})$ recorded for complex 3. The catalytic process as monitored by $^{1}$H NMR spectroscopy (isolation of 3, 5-DTBQ) and iodometric titration revealed the formation of H$_{2}$O$_{2}$ and thus implied …


An Efficient Water-Mediated Synthetic Route For The Alkylation Of Heteroarenes, Pinar Seyi̇tdanlioğlu, Essam Hamied Ahmed Hanashalhalshahaby, Canan Ünaleroğlu Jan 2018

An Efficient Water-Mediated Synthetic Route For The Alkylation Of Heteroarenes, Pinar Seyi̇tdanlioğlu, Essam Hamied Ahmed Hanashalhalshahaby, Canan Ünaleroğlu

Turkish Journal of Chemistry

An efficient synthetic route has been described for the alkylation of 1$H$-indole, 1$H$-benzimidazole, and 1$H$-benzotriazole. This approach features the alkylation of heteroaromatics through in situ generated enones from ketonic Mannich bases under metal-free conditions. A series of alkylated heteroaromatics have been synthesized via the K10 catalyzed alkylation reactions of these heteroaromatics with a variety of ketonic Mannich bases. Environmentally benign K10 catalyst, water-mediated mild reaction conditions, and the efficient synthesis of alkylated products are the advantages of this alkylation method.


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 …


Facile Synthesis Of Heteroaryl Substituted -Lactams From Nitrovinyl Arenes, Seda Çinar, Canan Ünaleroğlu Jan 2018

Facile Synthesis Of Heteroaryl Substituted -Lactams From Nitrovinyl Arenes, Seda Çinar, Canan Ünaleroğlu

Turkish Journal of Chemistry

Aliphatic nitroalkanes with different functional groups were synthesized from the Michael addition reactions of active methylene compounds 2 and nitrovinyl arenes 1 in high yields. The synthesized Michael adducts were subjected to intramolecular cyclization to give heteroaryl substituted γ-lactams in good to high yields under mild reaction conditions.


Organic Modification Of Montmorillonite And Effect Of Catalytic Selectivity On Thedimerization Of Unsaturated Fatty Acid, Xue Huang, Guoqiang Yin, Guangzhu Feng Jan 2018

Organic Modification Of Montmorillonite And Effect Of Catalytic Selectivity On Thedimerization Of Unsaturated Fatty Acid, Xue Huang, Guoqiang Yin, Guangzhu Feng

Turkish Journal of Chemistry

This study describes the selective synthesis of C36-dimer fatty acids, by reacting unsaturated fatty acid at 533 K for 6 h in the presence of montmorillonite and lithium chloride as the catalyst and cocatalyst, respectively. The catalytic performance of different montmorillonite and organic modified montmorillonite catalysts was investigated in the dimerization of technical grade unsaturated fatty acid, and the influence of the catalyst structure and composition on the catalytic performance was analyzed. All the samples were characterized by X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscopy (TEM), thermogravimetry (TG), and dispersion experiments. The results …


Kinetics Of Silver(I)-Catalyzed Oxidation Of Allyl Alcohol By Peroxodiphosphate Inacetate Buffers, Priyamvada Sharma, Riya Sailani, Deepmala Pareek, Chandra Lata Khandelwal Jan 2018

Kinetics Of Silver(I)-Catalyzed Oxidation Of Allyl Alcohol By Peroxodiphosphate Inacetate Buffers, Priyamvada Sharma, Riya Sailani, Deepmala Pareek, Chandra Lata Khandelwal

Turkish Journal of Chemistry

The kinetics and mechanism of silver(I)-catalyzed oxidation of allyl alcohol with peroxodiphosphate in acetate buffers have been studied. The rate is independent of allyl alcohol concentration. The effect of other reaction parameters such as hydrogen and acetate ions has also been studied. The rate law accounting for all experimental observations corresponds to the proposed mechanism. The energy and entropy of activation have also been evaluated by employing Eyring plots.


Experimental And Theoretical Studies Of Carbazole-Based Schiff Base As A Fluorescent Fe$^{3+}$ Probe, Hakan Kandemi̇r, Abdulkadi̇r Koçak, Süreyya Oğuz Tümay, Bünyemi̇n Çoşut, Yunus Zorlu, İbrahi̇m Fazil Şengül Jan 2018

Experimental And Theoretical Studies Of Carbazole-Based Schiff Base As A Fluorescent Fe$^{3+}$ Probe, Hakan Kandemi̇r, Abdulkadi̇r Koçak, Süreyya Oğuz Tümay, Bünyemi̇n Çoşut, Yunus Zorlu, İbrahi̇m Fazil Şengül

Turkish Journal of Chemistry

Synthesis of a new (E)-N1-((9-ethyl-9H-carbazol-3-yl)methylene)-5-nitrobenzene-1,2-diamine as a fluorescent chemosensor for selective detection of Fe$^{3+}$ ion over a number of other metal ions is described. The method for the synthesis of the carbazole Schiff base was based on the condensation of carbazole-3-carbaldehyde with 4-nitro-o-phenyldiamine in dimethylformamide in a moderate yield. The structure of the final compound was characterized by $^{1}$H NMR, $^{13}$C NMR, IR, mass spectrometry, and single crystal X-ray diffraction. The final compound exhibited exceptional selective and sensitive turn-on fluorescence response to the Fe$^{3+}$ cation. The fluorescent intensity of the final compound was increased 20-fold and the stoichiometry ratio of …


The Synthesis Of New Oxindoles As Analogs Of Natural Product 3,3$^\Prime $-Bis(Indolyl)Oxindole And In Vitro Evaluation Of The Enzyme Activity Of G6pd And 6pgd, Si̇nan Bayindir, Adnan Ayna, Yusuf Temel, Mehmet Çi̇ftci̇ Jan 2018

The Synthesis Of New Oxindoles As Analogs Of Natural Product 3,3$^\Prime $-Bis(Indolyl)Oxindole And In Vitro Evaluation Of The Enzyme Activity Of G6pd And 6pgd, Si̇nan Bayindir, Adnan Ayna, Yusuf Temel, Mehmet Çi̇ftci̇

Turkish Journal of Chemistry

Natural and synthetic derivatives that contain an indole core are being used in medical treatments and technological processes. Therefore, the development of new synthetic methods for the synthesis of indole derivatives is very popular. In this study, new oxindoles with reaction of 4,7-dihydro-1$H$-indole (2) and isatin (4) were synthesized as analogs of natural product 3,3$^\prime $-bis(indolyl)oxindole. The biological properties of the compounds obtained during this study were also studied, showing that compounds 5, 7, and 12 inhibited the activity of G6PD with an IC$_{50}$ of 99 $\mu $M, 231 $\mu $M, and 304 $\mu $M respectively. The activity of rat …


Development Of A Molecularly Imprinted Polymer-Based Electrochemical Sensor For Tyrosinase, Aysu Yarman Jan 2018

Development Of A Molecularly Imprinted Polymer-Based Electrochemical Sensor For Tyrosinase, Aysu Yarman

Turkish Journal of Chemistry

For the first time a molecularly imprinted polymer (MIP)-based sensor for tyrosinase is described. This sensor is based on the electropolymerization of scopoletin or o-phenylenediamine in the presence of tyrosinase from mushrooms, which has a high homology to the human enzyme. The template was removed either by treatment with proteinase K or by alkaline treatment. The measuring signal was generated either by measuring the formation of a product by the target enzyme or by evaluation of the permeability of the redox marker ferricyanide. The o-phenylenediamine-based MIP sensor has a linear measuring range up to 50 nM of tyrosinase with a …


Protein Ion-Exchange Chromatography On A Biomacromolecule-Immobilized Monolithic Cryogel, Ahmet Eren Özkan, Idris Guven, Orhan Gezici Jan 2018

Protein Ion-Exchange Chromatography On A Biomacromolecule-Immobilized Monolithic Cryogel, Ahmet Eren Özkan, Idris Guven, Orhan Gezici

Turkish Journal of Chemistry

An efficient and inexpensive monolithic stationary phase (PHEMA-HA) has been prepared through an easy process comprising addition of humic acid (HA) to a mixture of 2-hydroxyethyl methacrylate (HEMA) and N,N'-methylenebisacrylamide (MBAAm) and subsequent radical-polymerization at -20 $^{\circ}$C. The prepared monolithic material was characterized in terms of various techniques and methods such as elemental analysis, FTIR spectroscopy, scanning electron microscopy, mercury porosimetry, hydrolytic stability tests, pH$_{pzc}$ measurements, water-holding capacity, and water permeability. The amount of HA incorporated into the structure was calculated as 45 mg/g from the elemental analysis results. The study was conceptualized on the basis of protein ion-exchange chromatography, …


Peg-Peptide Conjugate Containing Cathepsin B Degradation Unit As A Doxorubicin Carrier System, Nesli̇gül Şentürk, Ayben Top Jan 2018

Peg-Peptide Conjugate Containing Cathepsin B Degradation Unit As A Doxorubicin Carrier System, Nesli̇gül Şentürk, Ayben Top

Turkish Journal of Chemistry

A drug delivery system (DDS) containing a cathepsin B degradable sequence and pH-responsive histidines was prepared by methoxypolyethylene glycol and peptide conjugation. Doxorubicin was attached to the carrier system using amide linkage to give the final form of the DDS, denoted as mPEG-AT3-DOX. mPEG-AT3-DOX exhibited a bimodal size distribution at about 15 and 30 nm independent of pH, whereas the size of the control DDS containing no peptide sequence, mPEG-DOX, was measured as $\sim$ 15-20 nm. At the end of 72 h, % doxorubicin release from both of the DDSs was observed to be below 8.5 $\pm$ 3% in the …


A Novel Hypobromous Acid Scavenging Activity Assay Using $P$-Cresol As A Spectrofluorometric Probe, Burcu Bekdeşer, Gülüzar Zeytünlü, Mustafa Özyürek, Mustafa Reşat Apak Jan 2018

A Novel Hypobromous Acid Scavenging Activity Assay Using $P$-Cresol As A Spectrofluorometric Probe, Burcu Bekdeşer, Gülüzar Zeytünlü, Mustafa Özyürek, Mustafa Reşat Apak

Turkish Journal of Chemistry

In this study, a novel spectrofluorometric assay based on $p$-cresol (4-methyl phenol) probe is developed for the measurement of HOBr scavenging activity. It is the first study involving the use of a $p$-cresol probe for the determination of the HOBr scavenging activity of biothiols. While the $p$-cresol probe ($\lambda_{ex}$ = 260 nm, $\lambda_{em}$ = 305 nm) has fluorescence characteristics, its brominated derivatives emerging at the end of the oxidation reaction with HOBr do not show fluorescence. The initial fluorescence intensity of the $p$-cresol probe is decreased in the presence of the brominating agent, HOBr, and this decrease is lower in …


Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi Jan 2018

Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi

Turkish Journal of Chemistry

In this work, the electrochemical oxidation of deferasirox at a multiwall carbon nanotube paste electrode (MWCNTPE) was described. The electrochemical behavior of deferasirox was studied using cyclic voltammetry and chronoamperometry techniques and parameters such as charge transfer coefficient ($\alpha )$, the number of electrons involved in the rate-determining step ($n_{a})$, and diffusion coefficient ($D)$ were calculated. The capability of the electrode for the determination of deferasirox at low concentrations was investigated using the differential pulse voltammetry technique. It was found that the calibration graph of deferasirox was linear in the concentration range of 0.16-16.5 $\mu $M and its detection limit …


Biological Evaluation And Synthesis Of New Pyrimidine-2(1h)-Ol/-Thiol Derivatives Derived From Chalcones Using The Solid Phase Microwave Method, Seda Fandakli, Nuran Kahri̇man, Tayyi̇be Beyza Yücel, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2018

Biological Evaluation And Synthesis Of New Pyrimidine-2(1h)-Ol/-Thiol Derivatives Derived From Chalcones Using The Solid Phase Microwave Method, Seda Fandakli, Nuran Kahri̇man, Tayyi̇be Beyza Yücel, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

Twenty-five new hydroxy- and methoxy-substituted 4,6-diarylpyrimidin-2(1H)-ol (20-34) and 4,6-diarylpyri\-midine-2(1H)-thiol derivatives (35-44) were synthesized from the reaction of the corresponding 1,3-diaryl-2-propene-1-one compounds (1-19) with urea or thiourea using the solid-phase microwave method. All the new synthetic compounds (20-44) were evaluated with regard to their $\alpha $-glucosidase activity. However, only compounds 22-25, 27,31,34, 35,37, and 40 exhibited a greater inhibitory effect than standard acarbose. The IC$_{50}$ values of the active compounds ranged between 2.36 and 13.34 $\mu $M. The 25 new compounds were also screened for their in vitro pancreatic lipase activity and compounds 20-27and 35-39 were found to be active. Of …


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 …


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 …


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, …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


Syntheses And Characterizations Of Cyclotriphosphazenes Containing A 4-Oxy-1-Naphthaldehyde Group, Hani̇fe İbi̇şoğlu, Esra Tanriverdi̇ Eçi̇k, Gönül Yeni̇lmez Çi̇ftçi̇ Jan 2018

Syntheses And Characterizations Of Cyclotriphosphazenes Containing A 4-Oxy-1-Naphthaldehyde Group, Hani̇fe İbi̇şoğlu, Esra Tanriverdi̇ Eçi̇k, Gönül Yeni̇lmez Çi̇ftçi̇

Turkish Journal of Chemistry

The nucleophilic substitution reaction of hexachlorocyclotriphosphazene (N$_{3}$P$_{3}$Cl$_{6}$, trimer) (1) with 4-hydroxy-1-naphthaldehyde (2) has been investigated for the first time. 4$^{{\prime}} $-Oxy-1$^{{\prime}} $-naphthaldehyde substituted mono- (3), bis- (4), and tris- (5) cyclotriphosphazenes were obtained from the nucleophilic substitution of compound 1 with 2 in a 1:2 molar ratio in the presence of Cs$_{2}$CO$_{3}$ in acetone at reflux. The pentakis-(6) and hexakis-substituted (7) cyclotriphosphazenes were prepared from the reaction of 1 with 2 in a 1:7 molar ratio using K$_{2}$CO$_{3}$ as a proton abstractor in tetrahydrofuran at room temperature. The structures of the new compounds (3-7) were determined by elemental analysis, FT-IR, …