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Articles 6991 - 7020 of 15584

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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 …

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Structure And Mechanism Of A Bacterial T6a Biosynthesis System, Amit Luthra, William Swinehart, Susan Bayooz, Phuc Phan, Boguslaw Stec, Dirk Iwata-Reuyl, Manal A. Swairjo Jan 2018

Structure And Mechanism Of A Bacterial T6a Biosynthesis System, Amit Luthra, William Swinehart, Susan Bayooz, Phuc Phan, Boguslaw Stec, Dirk Iwata-Reuyl, Manal A. Swairjo

Chemistry Faculty Publications and Presentations

The universal N(6)-threonylcarbamoyladenosine (t6A) modification at position 37 of ANN-decoding tRNAs is central to translational fidelity. In bacteria, t6A biosynthesis is catalyzed by the proteins TsaB, TsaC/TsaC2, TsaD and TsaE. Despite intense research, the molecular mechanisms underlying t6A biosynthesis are poorly understood. Here, we report biochemical and biophysical studies of the t6A biosynthesis system from Thermotoga maritima. Small angle X-ray scattering analysis reveals a symmetric 2:2 stoichiometric complex of TsaB and TsaD (TsaB2D2), as well as 2:2:2 complex (TsaB2D2E2), in …

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Facile Synthesis Of Ligand-Free Iridium Nanoparticles And Their In Vitro Biocompatibility, Anna L. Brown, Hayden Winter, Andrea M. Goforth, Gaurav Sahay, Conroy Sun Jan 2018

Facile Synthesis Of Ligand-Free Iridium Nanoparticles And Their In Vitro Biocompatibility, Anna L. Brown, Hayden Winter, Andrea M. Goforth, Gaurav Sahay, Conroy Sun

Chemistry Faculty Publications and Presentations

High-density inorganic nanoparticles have shown promise in medical applications that utilize radiation including X-ray imaging and as radiation dose enhancers for radiotherapy. We have developed an aqueous synthetic method to produce small (~ 2 nm) iridium nanoparticles (IrNPs) by reduction of iridium(III) chloride using a borohydride reducing agent. Unlike other solution-based synthesis methods, uniform and monodispersed IrNPs are produced without the use of surfactants or other solubilizing ligands. These nanoparticles are highly crystalline as observed by X-ray diffraction and high-resolution transmission electron microscopy (TEM). In vitro metabolic toxicity assays using hepatocyte and macrophage cells demonstrate that both IrNPs and iridium(III) …

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Adsorption Of Anionic And Cationic Dyes On Biochars, Produced By Hydrothermalcarbonization Of Waste Biomass: Effect Of Surface Functionalization And Ionicstrength, Ezgi̇ Çağlar, Yusuf Osman Donar, Ali̇ Sinağ, İbrahi̇m Bi̇roğul, Selva Bi̇lge, Kivanç Aydincak, Oleksii Pliekhov Jan 2018

Adsorption Of Anionic And Cationic Dyes On Biochars, Produced By Hydrothermalcarbonization Of Waste Biomass: Effect Of Surface Functionalization And Ionicstrength, Ezgi̇ Çağlar, Yusuf Osman Donar, Ali̇ Sinağ, İbrahi̇m Bi̇roğul, Selva Bi̇lge, Kivanç Aydincak, Oleksii Pliekhov

Turkish Journal of Chemistry

In this work, surface-functionalization agents and various salts as auxiliaries were used to improve the adsorption capacity of biochars produced via hydrothermal carbonization of glucose, cellulose, and hazelnut shell. The effect of surface functionalization with different acids and bases as well as neutral salts on the adsorption of methylene blue and methyl orange was investigated using Boehm titration, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy techniques. Surface functionalization of biochars leads to an increase in the number of oxygen-containing functional groups on the surface, thus increasing the adsorption capacity. To probe the influence of ionic strength on the adsorption …

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Synthesis And Antioxidant, Aggregation, And Electronic Properties Of6-Tert-Butyl-1,4-Benzodioxine Substituted Phthalocyanines, Mehmet Sali̇h Ağirtaş, Beyza Cabi̇r, Selçuk Gümüş, Sadi̇n Özdemi̇r, Abdurrahman Dündar Jan 2018

Synthesis And Antioxidant, Aggregation, And Electronic Properties Of6-Tert-Butyl-1,4-Benzodioxine Substituted Phthalocyanines, Mehmet Sali̇h Ağirtaş, Beyza Cabi̇r, Selçuk Gümüş, Sadi̇n Özdemi̇r, Abdurrahman Dündar

Turkish Journal of Chemistry

As a starting material, 7-tert-butyldibenzo [b,e] [1,4] dioxine-2,3-dicarbonitrile was prepared by the reac- tion of 4-tert-butylcatechol with 4,5-dichlorophthalonitrile. Metallophthalocyanine complexes 4-7 were obtained by cyclotetramerization of 7-tert-butyldibenzo [b,e] [1,4] dioxine-2,3-dicarbonitrile. All compounds were characterized by elemental analysis and other spectroscopic methods (IR, UV/Vis, and $^{1}$H NMR). Phthalocyanine compounds remained nonaggregated in tetrahydrofuran at the studied concentration ranges. Metallophthalocyanines 4-7 were tested for their antioxidant activities. The antioxidant activity processes included evaluation of radical-scavenging activity, chelat- ing activity, and reducing power. These compounds were compared to standard antioxidant ascorbic acid. The electronic data of the new compounds were obtained by computational …

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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 …

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Synthesis And Biological Properties Of Novel1-Methyl-2-(2-(Prop-2-Yn-1-Yloxy)Benzylidene) Hydrazine Analogues, Ari̇f Kivrak, Can Yilmaz, Meti̇n Konuş, Hali̇l Koca, Selahatti̇n Aydemi̇r, Jeger Ali Oagaz Jan 2018

Synthesis And Biological Properties Of Novel1-Methyl-2-(2-(Prop-2-Yn-1-Yloxy)Benzylidene) Hydrazine Analogues, Ari̇f Kivrak, Can Yilmaz, Meti̇n Konuş, Hali̇l Koca, Selahatti̇n Aydemi̇r, Jeger Ali Oagaz

Turkish Journal of Chemistry

1-Methyl-2-(2-(prop-2-yn-1-yloxy)benzylidene)hydrazine analogues were readily prepared in good yields by the reaction of 2-(prop-2-yn-1-yloxy)benzaldehydes and methyl hydrazine. The reaction tolerates a variety of substituents on the 2-hydroxybenzaldehyde to form nitro-, halo-, methoxy-, and naphthyl-substituted 1-methyl-2-(2-(prop-2-yn-1-yloxy)benzylidene)hydrazines. The in vitro antioxidant capacity measurements revealed that among all the analyzed hydrazine analogues that surpassed the Trolox standard, 1-(2-(but-3-ynyl)-5-nitrobenzylidene)-2-methylhydrazine had the maximum value, which was approximately 1.7 times that of Trolox.

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Nickel(Ii)-Pph$_{3}$ Complexes With Ons And Onn Chelating Thiosemicarbazones: Synthesis And Inhibition Potential On Influenza A Viruses, Şükri̇ye Güveli̇, Kadi̇r Turan, Bahri̇ Ülküseven Jan 2018

Nickel(Ii)-Pph$_{3}$ Complexes With Ons And Onn Chelating Thiosemicarbazones: Synthesis And Inhibition Potential On Influenza A Viruses, Şükri̇ye Güveli̇, Kadi̇r Turan, Bahri̇ Ülküseven

Turkish Journal of Chemistry

Tetra-coordinated nickel(II) complexes of two ONS (1, \2) and seven ONN (3a-3g) chelating 2-hydroxy-3-methoxy-benzaldehyde thiosemicarbazones were synthesized. The dibasic ligands and complexes bearing PPh$_{3}$ as a coligand were characterized by means of analytical and spectroscopic data. Cytotoxic activities of the ligands and nickel(II) complexes were determined using the MTT assay in vitro against MDCK cells, and then all the compounds were tested on influenza virus replication by plaque assays. The compounds showed GI$_{50}$ values varying from concentrations of 15.9 up to 161.8 $\mu$ g/mL for MDCK cells. The plaque assays indicated that one ONS (1) and two ONN (3c and …

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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, …

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Transfer Of The Protonable Surfactant Dipalmitoyl-Phosphatidylcholine Across A Large Liquid/Liquid Interface: A Voltammetric Study, İbrahi̇m Uyanik Jan 2018

Transfer Of The Protonable Surfactant Dipalmitoyl-Phosphatidylcholine Across A Large Liquid/Liquid Interface: A Voltammetric Study, İbrahi̇m Uyanik

Turkish Journal of Chemistry

Adsorption behavior of the zwitterionic phospholipid dipalmitoyl-phosphatidylcholine (DPPC) at the polarizable liquid/liquid interface formed between water and 1,2-dichloroethane electrolyte solutions is studied taking into account both the pH of the aqueous phase and the concentration of the phospholipid in the organic phase by cyclic voltammetry. Experimental results showed that the adsorption of the phospholipid strongly depends on the pH of the aqueous phase, which determines the surface ionization of the polar head of the phospholipid molecule and hence the stability of the adsorbed layer of phospholipids.

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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 …

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Oxime-Containing Acetylcholinesterase Reactivators And Their Complexes With Pd(Ii) And Pt(Ii) Ions: Recent Developments, Ivayla Pantcheva, Ahmed Nedzhib, Liudmil Antonov Jan 2018

Oxime-Containing Acetylcholinesterase Reactivators And Their Complexes With Pd(Ii) And Pt(Ii) Ions: Recent Developments, Ivayla Pantcheva, Ahmed Nedzhib, Liudmil Antonov

Turkish Journal of Chemistry

The ability of oxime-containing acetylcholinesterase reactivators BT-07 (K005), BT-08 (K033), BT-07-4M (K074), and obidoxime (H$_{2}$LX$_{2}$, X = Cl$^{-}$, Br$^{-})$ to bind palladium(II) or platinum(II) cations was evaluated in aqueous solutions (pH 7.4) at metal-to-ligand molar ratio varying from 1:10 to 10:1. Spectral changes were monitored within a week after mixing the reagents in the range from 220 nm to 500 nm. Results showed that depending on chemical structure and reaction time, oximes form two complex species of composition, [MHL]$^{3+}$ or [M$_{2}$L]$^{4+}$ (M = Pd(II), Pt(II)). It was also found that complexation of platinum(II) ions proceeds slower as compared to palladium(II). …

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Application Of A Pencil Graphite Electrode For Voltammetric Simultaneous Determination Of Ascorbic Acid, Norepinephrine, And Uric Acid In Real Samples, Abdulkadi̇r Levent, Günay Önal Jan 2018

Application Of A Pencil Graphite Electrode For Voltammetric Simultaneous Determination Of Ascorbic Acid, Norepinephrine, And Uric Acid In Real Samples, Abdulkadi̇r Levent, Günay Önal

Turkish Journal of Chemistry

A pencil graphite electrode (PGE) was used for the simultaneous detection of ascorbic acid (AA), norepinephrine (NE), and uric acid (UA) by differential pulse voltammetry and cyclic voltammetry. The anodic peaks of AA, NE, and UA in their mixture can be well separated in 0.1 M Britton--Robinson buffer solution at pH 4.0. The effects of various experimental parameters such as pH, scan rate, and voltammetric parameters on the voltammetric response of these compounds were investigated. Under optimum conditions, linear calibration graphs were obtained from the AA, NE, and UA concentration ranges, which were 100-800 nM, 20-170 nM, and 40-175 nM, …

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Removal Of Five Cationic Dyes Using A Resin Coated With Nickel/Nickel Boride Nanoparticles, Merve Çinar, Yasemi̇n İşlek Coşkun, Tüli̇n Deni̇z Çi̇ftçi̇ Jan 2018

Removal Of Five Cationic Dyes Using A Resin Coated With Nickel/Nickel Boride Nanoparticles, Merve Çinar, Yasemi̇n İşlek Coşkun, Tüli̇n Deni̇z Çi̇ftçi̇

Turkish Journal of Chemistry

Resins coated with nickel/nickel boride nanoparticles were used to remove brilliant green, methyl violet, methylene blue, phenosafranine, and brilliant cresyl blue from water. The effects of pH, adsorbent dose, contact time, and initial dye concentration on the adsorption efficiencies were investigated. The point of zero charge for the adsorbent was pH 9.5. Isotherm studies were conducted using Langmuir, Freundlich, and Dubinin--Radushkevich models, and thermodynamic studies were also performed. Adsorption of the five dyes was found to obey the Langmuir isotherm model and was endothermic. The maximum adsorption capacities calculated from the Langmuir isotherm were 66.7, 88.5, 144.9, 56.2, and 147.1 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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, …

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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 …

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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 …

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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 …

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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.

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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 …

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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, …

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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 …

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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 …

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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 …

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