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2017

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Articles 23761 - 23790 of 24647

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Synthesis And Antifungal Activity Of New Dihydrofurocoumarins And Dihydrofuroquinolines, Asli Ustalar, Mehmet Yilmaz, Agi̇m Osmani̇, Sema Aşkin Keçeli̇ Jan 2017

Synthesis And Antifungal Activity Of New Dihydrofurocoumarins And Dihydrofuroquinolines, Asli Ustalar, Mehmet Yilmaz, Agi̇m Osmani̇, Sema Aşkin Keçeli̇

Turkish Journal of Chemistry

We investigated the radical addition of 4-hydroxycoumarin (1a) and 4-hydroxyquinoline (1b) with conjugated dienes ({2a-f) mediated by cerium(IV) ammonium nitrate (CAN) resulting in ethenyl substituted 2,3-dihydrofurocoumarin (3a-f) and 3,5-dihydrofuroquinoline (3g, 3h) compounds in moderate to good yields. All compounds were characterized by spectroscopic methods (IR, MS, and $^{1}$H and $^{13}$C NMR) and microanalysis. Antifungal activities of these compounds were investigated against the fungi Candida albicans, C. parapsilosis, C. krusei, C. glabrata, C. tropicalis, and Aspergillus fumigatus.

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Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee Jan 2017

Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee

Turkish Journal of Chemistry

Various thioxo-quinazolino[3,4-$a$]quinazolinones were prepared and evaluated for their cytotoxicity in MOLT-4 (lymphoblastic leukemia) and MCF-7 (breast adenocarcinoma) cell lines. Synthesis of the target compounds was started from isatoic anhydride. Successive reaction of isatoic anhydride with benzylamine and 2-nitrobenzaldehyde, reduction of the nitro group, and reaction with CS$_{2}$ gave 12-benzyl-6-thioxo-6,7,11b,12-tetrahydro-13$H$-quinazolino[3,4-$a$]quinazolin-13-one. The latter compound reacted with various 2-chloro-$N$-substituted acetamides to afford the corresponding fused quinazolinone derivatives.

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Investigation Of The Effects Of Purification And Characterization Of Turkey (Meleagris Gallopavo) Liver Mitochondrial Thioredoxin Reductase Enzyme And Some Metal Ions On Enzyme Activity, Yusuf Temel, Ö. İrfan Küfrevi̇oğlu, Mehmet Çi̇ftci̇ Jan 2017

Investigation Of The Effects Of Purification And Characterization Of Turkey (Meleagris Gallopavo) Liver Mitochondrial Thioredoxin Reductase Enzyme And Some Metal Ions On Enzyme Activity, Yusuf Temel, Ö. İrfan Küfrevi̇oğlu, Mehmet Çi̇ftci̇

Turkish Journal of Chemistry

The thioredoxin system, found in all living creatures, consists of thioredoxin protein (Trx), thioredoxin reductase enzyme (TrxR), and NADPH. In this study, turkey liver mitochondrial TrxR enzyme with 3.07 EU $\times $ mg$^{-1}$ specific activity was purified 990-fold in a yield of 2.05{\%} using 2',5'-ADP Sepharose 4B affinity chromatography. The purity of the enzyme was measured and the molecular weight of its subunits was determined to be 45.5 kDa by SDS-PAGE. The molecular mass of the enzyme's natural state was found to be 88 kDa using Sephadex-G 150 gel filtration chromatography. In addition, characteristic and kinetic properties of the enzyme …

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Electrochemical Detection Of Dna Interaction With Mannich Base Derivatives By Disposable Graphite Electrodes, Hüseyi̇n İstanbullu, Hakan Karadeni̇z, Erçi̇n Erci̇yas, Kadri̇ye Arzum Erdem Gürsan Jan 2017

Electrochemical Detection Of Dna Interaction With Mannich Base Derivatives By Disposable Graphite Electrodes, Hüseyi̇n İstanbullu, Hakan Karadeni̇z, Erçi̇n Erci̇yas, Kadri̇ye Arzum Erdem Gürsan

Turkish Journal of Chemistry

Four different Mannich base derivatives containing an aromatic/heteroaromatic propanone structure (C1 (3-(dimethylamino)-1-(thiophen-2-yl)propan-1-one hydrochloride); C2 (3-morpholino-1-(pyridin-3-yl)propan-1-one hydrochloride); C3 (3-(dimethylamino)-1-(1H-indol-3-yl)propan-1-one hydrochloride), C4 (3-(piperidin-1-yl)-1-(pyren-1-yl)propan-1-one hydrochloride)) were earlier synthesized and characterized with $^{1}$H NMR, $^{13}$C NMR, MS, and elemental analysis. The interaction of these compounds with fish sperm double stranded DNA (fs-dsDNA) was investigated by using differential pulse voltammetry (DPV) in connection with a disposable pencil graphite electrode (PGE). After the interaction procedure, there was a meaningful decrease in the oxidation signal of the electroactive DNA base guanine due to possible intercalation and/or alkylation mechanism between these Mannich base derivatives and DNA. The features …

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Highly Selective Schiff Base Derivatives For Colorimetric Detection Of Al$^{3+}$, Zi̇ya Aydin, Mustafa Keleş Jan 2017

Highly Selective Schiff Base Derivatives For Colorimetric Detection Of Al$^{3+}$, Zi̇ya Aydin, Mustafa Keleş

Turkish Journal of Chemistry

Schiff base derivatives NBAR and NSAR were developed for selective detection of Al$^{3+}$ in aqueous solution. UV-vis spectroscopic studies revealed that NBAR and NSAR showed marked sensitivity and selectivity to Al$^{3+}$ in acetonitrile (ACN)/water (v/v, 1:1, pH 6.80). The NBAR and NSAR receptors bound Al$^{3+}$ in a 2:1 stoichiometry with apparent binding constants 4.09 $\times $ 10$^{11}$ M$^{-2}$ and 1.65 $\times $ 10$^{12}$ M$^{-2}$, respectively. They also displayed distinct changes in color upon the alteration of free Al$^{3+}$ levels in solution with reversible responses and showed little interference with other metal ions.

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Sonochemical Degradation Of Basic Red 29 In Aqueous Media, Zineb Boutamine, Slimane Merouani, Oualid Hamdaoui Jan 2017

Sonochemical Degradation Of Basic Red 29 In Aqueous Media, Zineb Boutamine, Slimane Merouani, Oualid Hamdaoui

Turkish Journal of Chemistry

In this work, the degradation of Basic Red 29 (BR29), an azo dye, was investigated using a high-frequency ultrasonic reactor (300 kHz). The influence of several parameters such as initial substrate concentration (5--200 mg L$^{-1})$, pH (3-10.1), ultrasonic power (20-80 W), and nature of the dissolved gas (Ar, air, and N$_{2})$ on the degradation of BR29 was assessed. Additionally, the impact of natural matrices (seawater and natural and river waters) on the degradation rate of BR29 was clarified. Degradation experiments with radical scavengers, tert-butyl alcohol and glucose, showed that BR29 degraded mainly through HO$^{\bullet }$ radical attack at the gas/liquid …

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Isocoumarins And 3,4-Dihydroisocoumarins, Amazing Natural Products: A Review, Aisha Saddiqa, Osman Çakmak, Muhammad Usman Jan 2017

Isocoumarins And 3,4-Dihydroisocoumarins, Amazing Natural Products: A Review, Aisha Saddiqa, Osman Çakmak, Muhammad Usman

Turkish Journal of Chemistry

The isocoumarins are naturally occurring lactones that constitute an important class of natural products exhibiting an array of biological activities. A wide variety of these lactones have been isolated from natural sources and, due to their remarkable bioactivities and structural diversity, great attention has been focused on their synthesis. This review article focuses on their structural diversity, biological applications, and commonly used synthetic modes.

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Spectrophotometric Determination Of Carmoisine After Cloud Point Extraction Using Triton X-114, Aslihan Karatepe, Çağri Akalin, Mustafa Soylak Jan 2017

Spectrophotometric Determination Of Carmoisine After Cloud Point Extraction Using Triton X-114, Aslihan Karatepe, Çağri Akalin, Mustafa Soylak

Turkish Journal of Chemistry

Carmoisine (E122) is a synthetic azo dye that is generally used to give a red color to food products. In this work, a sensitive and simple method was developed for the determination of carmoisine based on cloud point extraction. To obtain the optimum conditions for the extraction efficiency of carmoisine, the effects of different analytical parameters such as H$_{2}$SO$_{4}$ concentration, concentration of Triton X-114, and equilibrium temperature were studied. The calibration graph was linear between 0.05 and 5.0 $\mu $g/mL and the detection limit based on three times the standard deviation of the blank was 7.2 $\mu $g/L. The method …

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Syntheses And Photoluminescence Properties Of New Zn(Ii) And Cd(Ii) Coordination Polymers Prepared From 5-Sulfoisophthalate Ligand, Fati̇h Semerci̇ Jan 2017

Syntheses And Photoluminescence Properties Of New Zn(Ii) And Cd(Ii) Coordination Polymers Prepared From 5-Sulfoisophthalate Ligand, Fati̇h Semerci̇

Turkish Journal of Chemistry

New coordination polymers, formulated as {[Zn($\mu $-sipH)($\mu $-apim)]$\cdot $3H$_{2}$O} $_{n}$ (1) and {[Cd($\mu $-sip)(H$_{2}$O)$_{2}$ (apimH)]$\cdot $3H$_{2}$O}$_{n}$ (2) were synthesized based on the 1-(3-aminopropyl)imidazole (apim) along with 5-sulfoisophthalate (sip) ligands. The complexes were synthesized under mild hydrothermal conditions. All the complexes were characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffraction studies. The X-ray crystallographic studies of 1 and 2 reveal Zn(II) and Cd(II) ions are $\mu $-bridged by dianionic sipH and trianionic sip ligands in bis(monodentate) and bis(bidentate) coordination mode, respectively, to generate 1D polymer chains. In complex 1, the adjacent chains are linked by two apim ligands to …

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Impact Of Surface Modification Of Green Algal Biomass By Phosphorylation On The Removal Of Copper(Ii) Ions From Water, Zakaria Al-Qodah, Mohammad Al-Shannag, Abdulaziz Amro, Eman Assirey, Mustafa Bob, Khalid Bani-Melhem, Malek Alkasrawi Jan 2017

Impact Of Surface Modification Of Green Algal Biomass By Phosphorylation On The Removal Of Copper(Ii) Ions From Water, Zakaria Al-Qodah, Mohammad Al-Shannag, Abdulaziz Amro, Eman Assirey, Mustafa Bob, Khalid Bani-Melhem, Malek Alkasrawi

Turkish Journal of Chemistry

A series of batch lab-scale experiments were performed to investigate the performance of dead phosphorylated algal biomass of Spirogyra species for the bioadsorption of Cu$^{+2}$ ions from aqueous solutions. FT-IR and SEM analyses were performed to characterize the phosphorylated and raw algae. The SEM analysis indicated that the phosphorus content increases by about 5 times. The isotherm equilibrium data indicated that phosphorylation enhances the removal of Cu$^{+2}$ from water by about 20%. The experimental isotherms fit well to Langmuir models with $R^{2}$ values close to 0.99. Adsorption kinetic study was conducted to investigate the effect of initial Cu$^{+2}$ concentrations, pH, …

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Synthesis And Anticancer And Cytotoxic Effects Of Novel 1,4-Phenylene-Bis-N-Thiocarbamoylpyrazole And 1,4-Phenylene-Bis-Pyrazolylthiazole Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Yakup Budak, Ayşe Şahi̇n Yağlioğlu, Mustafa Ceylan Jan 2017

Synthesis And Anticancer And Cytotoxic Effects Of Novel 1,4-Phenylene-Bis-N-Thiocarbamoylpyrazole And 1,4-Phenylene-Bis-Pyrazolylthiazole Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Yakup Budak, Ayşe Şahi̇n Yağlioğlu, Mustafa Ceylan

Turkish Journal of Chemistry

Thiazolylpyrazoline derivatives were recently reported as potent anticancer agents. In this study, novel 1,4-phenylene-bis-N-thiocarbamoylpyrazoles (3a-h and 1,4-phenylene-bis-pyrazolylthiazoles (5a-h were prepared and screened for their anticancer activities against C6 (rat brain tumor cells) and HeLa (human uterus carcinoma). Anticancer activity studies were performed as a dose-dependent assay starting with eight concentrations. 5-Fluorouracil (5-FU) was used as a positive control. Compounds 3c, 3d, and 3h were examined and they revealed almost the same activities compared with 5-FU in terms of cell selectivity against C6 cells. Moreover, compounds 3a-h had lower cytotoxicity than 5-FU. The low cytotoxicity values of 3a-h as well as …

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Hydrolysis Of Ammonia Borane And Hydrazine Borane By Poly($N$-Vinyl-2-Pyrrolidone)-Stabilized Copd Nanoparticles For Chemical Hydrogen Storage, Murat Rakap, Bayram Abay, Ni̇hat Tunç Jan 2017

Hydrolysis Of Ammonia Borane And Hydrazine Borane By Poly($N$-Vinyl-2-Pyrrolidone)-Stabilized Copd Nanoparticles For Chemical Hydrogen Storage, Murat Rakap, Bayram Abay, Ni̇hat Tunç

Turkish Journal of Chemistry

For the first time the synthesis of poly($N$-vinyl-2-pyrrolidone)-stabilized cobalt-palladium nanoparticles by an easy method, their characterization, and their use as active catalysts for hydrogen release from hydrolysis of ammonia borane and hydrazine borane is reported here. The catalyst is prepared by simultaneous reduction of suitable cobalt and palladium ions by sodium borohydride in the presence of poly($N$-vinyl-2-pyrrolidone) as a stabilizer. They are characterized by UV-Vis spectroscopy, TEM analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. They provide average turnover frequencies of 30 min$^{-1}$ and 45 min$^{-1}$ in the hydrolysis of ammonia borane and hydrazine borane. They also provide activation energies of …

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Synthesis And In Vitro Anticancer Evaluation Of 1,4-Phenylene-Bis-Pyrimidine-2-Amine Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Ayşe Şahi̇n Yağlioğlu, Yakup Budak, Mustafa Ceylan Jan 2017

Synthesis And In Vitro Anticancer Evaluation Of 1,4-Phenylene-Bis-Pyrimidine-2-Amine Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Ayşe Şahi̇n Yağlioğlu, Yakup Budak, Mustafa Ceylan

Turkish Journal of Chemistry

A series of 1,4-phenylene-bis-chalcones 3a-3h were synthesized by the reaction of terephthalaldehyde with substituted arylketones in this study. The novel 1,4-phenylene-bis-pyrimidine-2-amine derivatives 5a-5h were obtained by the addition of guanidine hydrochloride to 1,4-phenylene-bis-chalcone 3a-3h in ethanolic KOH under reflux conditions. The structure of the compounds was explained by means of IR, $^{1}$H NMR, $^{13}$C NMR, and elemental analyses. The anticancer activities of 3a-3h and 5a-5h were investigated against rat brain tumor cells and human uterus carcinoma in vitro$.$ Activity tests were performed as dose-dependent assays at eight concentrations. The positive control was 5-fluorouracil (5-FU). Compounds 3c and 3d were examined …

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Investigation Of Solvent Effect On Photophysical Properties Of Some Sulfonamides Derivatives, Ebru Bozkurt, Hali̇se İnci̇ Gül, Mehtap Tuğrak Jan 2017

Investigation Of Solvent Effect On Photophysical Properties Of Some Sulfonamides Derivatives, Ebru Bozkurt, Hali̇se İnci̇ Gül, Mehtap Tuğrak

Turkish Journal of Chemistry

The photophysical properties of new sulfonamides synthesized recently were investigated in different solvents. Shifts in the absorption and fluorescence spectra of both compounds (S10 and S11) occurred depending on the solvents used. Ground and excited state dipole moments of the molecules were calculated using the spectral shifts of the compounds in different solvents and polarity function of solvents, respectively. They were 1.32 and 1.46 D for S10 and 1.71 and 4.89 D for S11. These results suggested that the excited state dipole moments are greater than those in ground state for both molecules. This means that the dyes were more …

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Efficient Multicomponent Synthesis Of 1,2,3-Triazoles Catalyzed By Cu(Ii) Supported On Pei@Fe$_{3}$O$_{4}$ Mnps In A Water/Peg$_{300}$ System, Zeinab Hassanpour, Aziz Maleki, Morteza Hosseini, Lena Gorgannezhad, Vajihe Nejadshafiee, Ali Ramazani, Ismaeil Haririan, Abbas Shafiee, Mehdi Khoobi Jan 2017

Efficient Multicomponent Synthesis Of 1,2,3-Triazoles Catalyzed By Cu(Ii) Supported On Pei@Fe$_{3}$O$_{4}$ Mnps In A Water/Peg$_{300}$ System, Zeinab Hassanpour, Aziz Maleki, Morteza Hosseini, Lena Gorgannezhad, Vajihe Nejadshafiee, Ali Ramazani, Ismaeil Haririan, Abbas Shafiee, Mehdi Khoobi

Turkish Journal of Chemistry

A highly dispersible and magnetically recoverable Cu-PEI@Fe$_{3}$O$_{4}$ MNPs catalyst was prepared and successfully applied in one-pot three-component coupling of terminal alkynes, sodium azide, and alkyl bromides/chlorides in water to give 1,4-disubstituted 1,2,3-triazoles with good to excellent yields. The catalyst was fully characterized with FT-IR, TGA, TEM, SEM, VSM, EDX, cyclic voltammetry, and ICP-AES spectroscopic techniques. Furthermore, the catalyst was easily recycled by an external magnet and successfully reused six times in the reaction without significant loss of its catalytic activity and copper leaching. The large-scale reaction was also carried out in the absence of any base and reducing agent even …

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Synthesis And Photovoltaic Characterization Of Triarylamine-Substituted Quinoxaline Push-Pull Dyes To Improve The Performance Of Dye-Sensitized Solar Cells, Kadi̇r Demi̇rak, Mustafa Can, Ci̇han Özsoy, Mesude Zeli̇ha Yi̇ği̇t, Burak Gülteki̇n, Şerafetti̇n Demi̇ç, Ceylan Zafer Jan 2017

Synthesis And Photovoltaic Characterization Of Triarylamine-Substituted Quinoxaline Push-Pull Dyes To Improve The Performance Of Dye-Sensitized Solar Cells, Kadi̇r Demi̇rak, Mustafa Can, Ci̇han Özsoy, Mesude Zeli̇ha Yi̇ği̇t, Burak Gülteki̇n, Şerafetti̇n Demi̇ç, Ceylan Zafer

Turkish Journal of Chemistry

Novel unsymmetrical organic sensitizers having donor, $\pi $-spacer, and anchoring groups were designed and synthesized for dye-sensitized solar cell (DSSC) application. The dyes 3-{4-[7-(4-{bis[4-(hexyl)phenyl]amino} phenyl)-11,12-dibutoxy-1,4,5,8-tetrahydrodibenzo [a, c] phenazine-2-yl]phenyl} -2-cyano acrylic acid (KD-148) and 3-{5-[7-(4-{bis[4-(hexyloxy)phenyl]amino} phenyl)-11,12-dibutoxy-1,4,5,8-tetrahydrodibenzo [a, c] phenazine-2-yl]-2-thienyl} -2-cyano acrylic acid (KD-150) were anchored onto TiO$_{2}$ and tested with ionic liquid electrolyte. The monochromatic incident photon-to-current conversion efficiencies (IPCE) of the dyes were 50% and 60% at 420 nm, respectively. The KD-150-sensitized solar cell gave a short-circuit current (I$_{SC})$ of 7.37 mA/cm$^{2}$, an open-circuit voltage (V$_{oc})$ of 560 mV, a fill factor (FF) of 0.56, and overall conversion efficiency ($\eta …

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Synthesis, Characterization, And Antimicrobial Activities Of Novel Monosaccharide-Containing Schiff Base Ligands, Fatma Telli̇, Stephen Thomas Astley, Azi̇ze Yeşi̇m Salman Jan 2017

Synthesis, Characterization, And Antimicrobial Activities Of Novel Monosaccharide-Containing Schiff Base Ligands, Fatma Telli̇, Stephen Thomas Astley, Azi̇ze Yeşi̇m Salman

Turkish Journal of Chemistry

Four new chiral Schiff base ligands (3a-4a, 3b-4b) have been prepared using aminoisopropylidene derivatives of glucose and aminochloralose derivatives of mannose. The synthesized compounds 1 and 2 were characterized by nuclear magnetic resonance ($^{1}$H and $^{13}$C NMR), Fourier transform infrared spectroscopy (FTIR), UV/visible spectroscopy, and elemental analysis. A total of eight Schiff base compounds (3a-6a, 3b-6b) were tested for antimicrobial activity against Escherichia coli ATCC 12228, Staphylococcus aureus ATCC 6538, Klebsiella pneumoniae CCM 2318, Pseudomonas aeruginosa ATCC 27853, Salmonella typhimurium CCM 5445, Enterococcus faecalis ATCC 29212, Bacillus subtilis ATCC 6633, and Candida albicans ATCC 10239 and exhibited a range of …

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Development Of A Sample Preparation Strategy For The Determination Of Tungsten In Soil Samples By Inductively Coupled Plasma Mass Spectrometry Using A Response Surface Methodology, Ümran Seven Erdemi̇r Jan 2017

Development Of A Sample Preparation Strategy For The Determination Of Tungsten In Soil Samples By Inductively Coupled Plasma Mass Spectrometry Using A Response Surface Methodology, Ümran Seven Erdemi̇r

Turkish Journal of Chemistry

An alternative rapid digestion method has been developed for the determination of tungsten (W) in soil samples using fractionation studies and response surface methodology. The digestion method using the Kjeldahl instrument was applied to samples, and soluble tungsten was determined via inductively coupled plasma mass spectrometry. Digestion parameters were selected depending on the results of fractionation studies and optimized using a four-factor and five-level central composite design. The contributions of the phosphoric acid concentration (X$_{1})$, digestion temperature (X$_{2})$, digestion time (X$_{3})$, and hydrochloric acid concentration (X$_{4})$ were evaluated for the determination of W from samples in which its levels were …

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Bis(Indoline-2,3-Diones): Versatile Precursors For Novel Bis(Spirooxindoles) Incorporating 4$H$-Chromene-3-Carbonitrile And Pyrano[2,3-$D$]Pyrimidine-6-Carbonitrile Derivatives, Said Ahmed Soliman Ghozlan, Muhammed Aly Ramadan, Amr Mohmed Abdelmoniem, Ahmed H. M. Elwahy, Ismail Abdelshafy Abdelhamid Jan 2017

Bis(Indoline-2,3-Diones): Versatile Precursors For Novel Bis(Spirooxindoles) Incorporating 4$H$-Chromene-3-Carbonitrile And Pyrano[2,3-$D$]Pyrimidine-6-Carbonitrile Derivatives, Said Ahmed Soliman Ghozlan, Muhammed Aly Ramadan, Amr Mohmed Abdelmoniem, Ahmed H. M. Elwahy, Ismail Abdelshafy Abdelhamid

Turkish Journal of Chemistry

Multicomponent reaction of dimedone or 1,3-dimethylbarbituric acid and malononitrile with a series of bis(indoline-2,3-diones) afforded the corresponding bis(2-amino-7,7-dimethyl-2',5-dioxo-5,6,7,8-tetrahydrospiro[chromene-4,3'-indoline]-3-carbonitrile) and bis(7'-amino-1',3'-dimethyl-2,2',4'-trioxo-1',2',3',4'-tetrahydrospiro[indoline-3,5'-pyrano [2,3-d]pyrimidine]-6'-carbonitrile) derivatives in good to excellent yield.

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Synthesis Of Novel Derivatives Of Chromenone Bearing An $N$-Carbamothioyl Moiety As Soybean 15-Lox Inhibitors, Robabeh Kaviani, Mina Saeedi, Mohammad Mahdavi, Hamind Nadri, Alireza Moradi, Abbas Shafiee, Tahmineh Akbarzadeh Jan 2017

Synthesis Of Novel Derivatives Of Chromenone Bearing An $N$-Carbamothioyl Moiety As Soybean 15-Lox Inhibitors, Robabeh Kaviani, Mina Saeedi, Mohammad Mahdavi, Hamind Nadri, Alireza Moradi, Abbas Shafiee, Tahmineh Akbarzadeh

Turkish Journal of Chemistry

Novel derivatives of chromenone bearing an $N$-carbamothioyl moiety were synthesized and evaluated for their soybean 15-LOX inhibitory activity. Synthesis of the target compounds was started from 7-hydroxy-2$H$-chromen-2-one. It was reacted with 1-fluoro-2(4)-nitrobenzene to obtain the corresponding nitrophenoxy-chromenone derivative. Reduction of the nitro group was achieved in the presence of Zn/NH$_{4}$Cl and reaction of the latter compound with in situ prepared benzoyl isothiocyanate led to the formation of the title compounds. All compounds were characterized and tested against soybean 15-LOX. Among them, 4-methyl-$N$-((4-((2-oxo-2$H$-chromen-7-yl)oxy)phenyl)carbamothioyl)benzamide (7l) showed the best activity as potent as the reference drug, quercetin.

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The Structure And Cytotoxic Activity Of A New Saponin: Cephoside A From Cephalaria Elazigensis Var. Purpurea, Peyker Kayce, Nazli Boke Sarikahya, Murat Pekmez, Nazli Arda, Suheyla Kirmizigul Jan 2017

The Structure And Cytotoxic Activity Of A New Saponin: Cephoside A From Cephalaria Elazigensis Var. Purpurea, Peyker Kayce, Nazli Boke Sarikahya, Murat Pekmez, Nazli Arda, Suheyla Kirmizigul

Turkish Journal of Chemistry

Investigation of the aerial parts of Cephalaria elazigensis var. purpurea afforded one new oleanane-type saponin, namely cephoside A (1), and five known natural compounds (2-6). Compound 2, named anemoclemoside A, which is an unusual triterpene glycoside, was identified in the family Dipsacaceae for the first time. Chemical structures of all compounds were determined on the basis of the HRESIMS and 1D and 2D NMR data. Cephoside A (1) and anemoclemoside A (2) were assessed for their cytotoxic activities against HeLa cells, having IC$_{50}$ values of 495 and 135 $\mu $g/mL, respectively.

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Stereoselective And Regioselective Synthesis Of $N$-Substituted Methyl 2-((Azolyl)Methyl)-3-Arylacrylates From Baylis-Hillman Acetates, Ayşen Köseceli̇ Özenç, İlhami̇ Çeli̇k, Şule Kökten Jan 2017

Stereoselective And Regioselective Synthesis Of $N$-Substituted Methyl 2-((Azolyl)Methyl)-3-Arylacrylates From Baylis-Hillman Acetates, Ayşen Köseceli̇ Özenç, İlhami̇ Çeli̇k, Şule Kökten

Turkish Journal of Chemistry

$N$-Substituted methyl 2-((azolyl)methyl)-3-arylacrylates were synthesized stereo- and regioselectively with one-pot reaction between Baylis--Hillman acetates and a suitable acylazole in the presence of K$_{2}$CO$_{3}$ as a base catalyst. The targeted $N$-substituted azole acrylates were efficiently obtained in good yields (39%-89%).

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Fabrication Of Multilayer Graphene Oxide-Reinforced High Density Polyethylene Nanocomposites With Enhanced Thermal And Mechanical Properties Via Thermokinetic Mixing, Burcu Saner Okan Jan 2017

Fabrication Of Multilayer Graphene Oxide-Reinforced High Density Polyethylene Nanocomposites With Enhanced Thermal And Mechanical Properties Via Thermokinetic Mixing, Burcu Saner Okan

Turkish Journal of Chemistry

High density polyethylene (HDPE) was compounded with thermally exfoliated graphene oxide (TEGO) by thermokinetic mixing in a short time. High shear rates during the compounding process provided high exfoliation and proper dispersion of graphene layers in the polymer matrix. Different TEGO/polymer ratios were used to get efficient melt mixing. Structural analysis by spectroscopic techniques confirmed the exfoliation of TEGO sheets and the coverage of their surfaces by HDPE chains. Furthermore, homogeneous dispersion of graphene sheets in the matrix led to the enhancement in the mechanical and thermal properties of HPDE-based nanocomposites. Especially stress concentration sites were significantly reduced by preventing …

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Dehydration Behavior And Kinetics Of Kurnakovite Under Microwave Irradiation, Fatma Tuğçe Şenberber, Meral Yildirim, İkli̇m Nergi̇z Özdoğan, Azmi̇ Seyhun Kipçak, Emek Derun Jan 2017

Dehydration Behavior And Kinetics Of Kurnakovite Under Microwave Irradiation, Fatma Tuğçe Şenberber, Meral Yildirim, İkli̇m Nergi̇z Özdoğan, Azmi̇ Seyhun Kipçak, Emek Derun

Turkish Journal of Chemistry

In this research, the dehydration behavior of kurnakovite was studied under microwave irradiation. The kinetic parameters of the dehydration reaction were determined using different kinetic models. Kurnakovite was characterized by the techniques of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) before and after the dehydration process. According to the results, kurnakovite was identified as a compound with the powder diffraction file (pdf) number 00-024-0700 before the dehydration process and after the dehydration process amorphous formations were observed. Moreover, FT-IR results showed that dehydration was completed successfully because of the disappearance in the band values …

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A Biochar-Modified Carbon Paste Electrode, Derya Bal Altuntaş, Gökçen Akgül, Jale Yanik, Ülkü Anik Jan 2017

A Biochar-Modified Carbon Paste Electrode, Derya Bal Altuntaş, Gökçen Akgül, Jale Yanik, Ülkü Anik

Turkish Journal of Chemistry

The present work examıned the use of biochar derived from tea waste as a novel electrode material. For the fabrication of the biochar electrode, suitable amounts of biochar and graphite were mixed with mineral oil for the first time. The electrochemical performance of the biochar-modified carbon paste electrode (BCPE) was measured by various cyclic voltammetric reactions for several redox systems. The factors affecting the electrode kinetics of BCPE surfaces were examined and optimized. The BCPE was applied as transducer in a glucose biosensor. The results reflect the effective properties of composite electrodes and the electrochemical properties of biochar showing that …

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A Rapid, Eco-Friendly, And Reliable Microplate Method For Determination Of Cr(Vi), Alejandro Coreño Alonso, Gustavo Cruz Jimenez, Leticia Lopez Martinez, Georgina Elena Reyna Lopez, Francisco Javier Acevedo Aguilar Jan 2017

A Rapid, Eco-Friendly, And Reliable Microplate Method For Determination Of Cr(Vi), Alejandro Coreño Alonso, Gustavo Cruz Jimenez, Leticia Lopez Martinez, Georgina Elena Reyna Lopez, Francisco Javier Acevedo Aguilar

Turkish Journal of Chemistry

In the present work, the reaction of Cr(VI) with 1,5-diphenylcarbazide in microplates (enzyme-linked immunosorbent assay microtiter plate) and a subsequent determination in a plate reader at 540 nm were performed. The final volume utilized for each determination was 200 $\mu $L, and the cost and waste were reduced for hexavalent chromium [Cr(VI)] quantification. The use of microplates allowed for the analysis of a large number of samples, reducing analysis time. No statistically significant differences were observed between the results obtained in the analysis of Cr(VI) in real samples by the conventional procedure and by the proposed methodology in this work …

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Microwave-Enhanced Fenton-Like Degradation By Surface-Modified Metal-Organic Frameworks As A Promising Method For Removal Of Dye From Aqueous Samples, Seyed Ershad Moradi, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Saeed Emami Jan 2017

Microwave-Enhanced Fenton-Like Degradation By Surface-Modified Metal-Organic Frameworks As A Promising Method For Removal Of Dye From Aqueous Samples, Seyed Ershad Moradi, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Saeed Emami

Turkish Journal of Chemistry

In the current research, the sulfonated metal-organic framework loaded on iron oxide nanoparticles, Fe$_{3}$O$_{4}$@MIL-100(Fe)-OSO$_{3}$H, has been synthesized and utilized as a Fenton-like catalyst for the decolorization of aqueous solutions containing methyl orange (MO) dye as a model organic pollutant. The morphology and structure of the catalyst were characterized by X-ray powder diffraction, transmission electron microscopy, Brunauer-Emmett-Teller analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, and UV-Vis diffuse reflectance spectroscopy. The effects of various parameters on MO degradation were investigated and the optimum conditions for MO degradation were found to be an initial concentration of MO of 100 mg/L, initial concentration of …

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Synthesis Of Na-, Fe-, And Co-Promoted Tio$_{2}$/Multiwalled Carbon Nanotube Composites And Their Use As A Photocatalyst, Alp Yürüm, Gürkan Karakaş Jan 2017

Synthesis Of Na-, Fe-, And Co-Promoted Tio$_{2}$/Multiwalled Carbon Nanotube Composites And Their Use As A Photocatalyst, Alp Yürüm, Gürkan Karakaş

Turkish Journal of Chemistry

The use of multiwalled carbon nanotubes (CNTs) in sol-gel synthesized titanium dioxide (TiO$_{2})$ photocatalysts as templates was systematically studied. CNTs have high oxidative thermal stability and the controlled removal of CNTs can be achieved at lower temperatures under air flow by the use of Na, Fe, and Co as a catalyst. These catalysts helped to reduce the oxidation temperature of CNTs; thus anatase phase was achieved without significant sintering. The use of a promoter, heat treatment, and various heat treatment atmospheres was effective in specific surface area, crystallinity, and photocatalytic activity against methylene blue (MB) degradation. While the specific surface …

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Singlet Oxygen Generation From Poly[4-Diacetoxyiodo]Styrene And Hydrogen Peroxide, Mustafa Çatir Jan 2017

Singlet Oxygen Generation From Poly[4-Diacetoxyiodo]Styrene And Hydrogen Peroxide, Mustafa Çatir

Turkish Journal of Chemistry

Treatment of hydrogen peroxide with a polymer-supported hypervalent iodine compound, poly[4-diacetoxyiodo] styrene (PDAIS), generates singlet molecular oxygen ($^{1}$O$_{2})$. Singlet oxygen generation was proved by trapping with typical organic compounds such as conjugated dienes, aromatic dienes, and electron-rich alkene. When compared to monomer analogue, the use of PDAIS in peroxidation of substrates gave slightly better yields (45%-96%). Regeneration and reuse of PDAIS showed similar activity. The mechanism underlying generation of singlet oxygen and reaction scope was examined.

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Synthesis Of Neodymium-Iron Nanoperovskite For Sensing Applications Of An Antiallergic Drug, Nada F. Atta, Mohammad H. Binsabt, Ekram H. El-Ads, Ahmed Galal Jan 2017

Synthesis Of Neodymium-Iron Nanoperovskite For Sensing Applications Of An Antiallergic Drug, Nada F. Atta, Mohammad H. Binsabt, Ekram H. El-Ads, Ahmed Galal

Turkish Journal of Chemistry

A facile route was used for the fabrication of NdFeO$_{3}$ (NF) perovskite. The orthorhombic structure of single phase nanocrystalline NdFeO$_{3}$ perovskite was confirmed by different characterization techniques: XRD, FTIR, TEM, BET, SEM, and EDAX. The nanoperovskite was successfully used as a sensor component with a carbon paste electrode (CpE) for the determination of ketotifen in pharmaceutical formulations. Ketotifen, an antiallergic drug, is utilized for the treatment of asthma attacks, rhinitis, skin allergies, and anaphylaxis. Sodium dodecyl sulfate (SDS) was employed in a surface assembly mode to improve the sensitivity of the sensor response. The proposed sensor, NdFeO$_{3}$ in situ modified …

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