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Polybrominated Methoxy- And Hydroxynaphthalenes, Kiymet Berki̇l Akar, Osman Çakmak, Tuncay Tunç
Polybrominated Methoxy- And Hydroxynaphthalenes, Kiymet Berki̇l Akar, Osman Çakmak, Tuncay Tunç
Turkish Journal of Chemistry
Regio- and stereoselective synthesis are described for convenient preparation of hydroxy- and methoxynaphthalenes starting from naphthalene (\textbf{1}). \textit{cis,cis,trans}-2,3,5,8-Tetrabromo-4-methoxy-1,2,3,4-tetrahydronaphthalen-1-ol (\textbf{6}), \textit{cis,cis,trans}-2,3,5,8-tetrabromo-1,4-dimethoxy-1,2,3,4-tetrahydronaphthalene (\textbf{7}), and \textit{cis,cis,cis}-2,3,5,8-tetrabromo-1,4-dimethoxy-1,2,3,4-tetrahydronaphthalene (\textbf{8}) were obtained with silver-induced substitution of \textit{trans,cis,trans}-1,2,3,4, 5,8-hexabromo-1,2,3,4-tetrahydronaphthalene (\textbf{3}). Base-promoted aromatization of dimethoxides \textbf{7} and \textbf{8} afforded 3,5,8-tribromo-1-methoxynaphthalene (\textbf{9}) and 2,5,8-tribromo-1-methoxynaphthalene (\textbf{10}). The reaction of \textbf{6 }with sodium methoxide formed compounds \textbf{10 }and 3,5,8-tribromonaphthalen-1-ol (\textbf{16}). Bromination of \textbf{9} and\textbf{ 16} with Br$_{2}$ in dichloromethane at room temperature produced 2,3,5,8-tetrabromo-1-methoxynaphthalene (\textbf{14}) and 2,3,4,5,8-pentabromonaphthalen-1-ol (\textbf{18}), respectively, while compound \textbf{10} did not react in the same conditions. Pyridine-induced elimination of hexabromide \textbf{3} afforded 1,4,6\textbf{-}tribromnaphthalene (\textbf{21}) in 99{\%} yield and …
New Antimicrobial Biscembrane Hydrocarbon And Cembranoid Diterpenes From The Soft Coral Sarcophyton Trocheliophorum, Muhammad Zubair, Walied Alarif, Khalid Al-Footy, Mohamed Ph, Magda Ali, Salim Basaif, Sultan Al-Lihaibi, Seif-Eldin Ayyad
New Antimicrobial Biscembrane Hydrocarbon And Cembranoid Diterpenes From The Soft Coral Sarcophyton Trocheliophorum, Muhammad Zubair, Walied Alarif, Khalid Al-Footy, Mohamed Ph, Magda Ali, Salim Basaif, Sultan Al-Lihaibi, Seif-Eldin Ayyad
Turkish Journal of Chemistry
A new tetracyclic biscembrane hydrocarbon, trocheliane (1), along with two new cembranoid diterpenes, sarcotrocheldiol A (2) and B (3), and the known diterpene cembrene-C (4), were isolated from the Red Sea soft coral Sarcophyton trocheliophorum. The structures and relative stereochemistry of the compounds were elucidated by interpretation of MS, 1 D NMR, and 2 D NMR experiments. The sensitivity of some pathogenic bacteria used as test organisms to the new compounds 1-3 was determined. 1 showed appreciable antimicrobial activity with the diameter of inhibition zones ranging from 11 to 18 mm. 1 was active against the two multidrug resistant bacteria …
Synthesis And Evaluation Of Novel $N,N'$-Disubstituted Benzimidazolium Bromides Salts As Antitumor Agents, Hasan Küçükbay, Akin Mumcu, Suat Teki̇n, Süleyman Sandal
Synthesis And Evaluation Of Novel $N,N'$-Disubstituted Benzimidazolium Bromides Salts As Antitumor Agents, Hasan Küçükbay, Akin Mumcu, Suat Teki̇n, Süleyman Sandal
Turkish Journal of Chemistry
Novel benzimidazolium bromides salts having (4-methoxyphenyl)ethyl, (phthalimide-2-yl)methyl, 4-nitro- benzyl, 2-phenylethyl, penthyl, or allyl groups were synthesized and their characterizations were conducted by $^{1}$H and $^{13}$C NMR and IR spectroscopic methods, and microanalysis. In vitro antitumor activities of the novel benzimidazole compounds (1-7) were determined by using ovarian (A2780) and prostate (PC-3) cancer cell lines. Antitumor properties of all compounds were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. A time-dependent cell viability assay for the tested benzimidazole compounds was performed and the IC$_{50}$ values of the compounds were calculated after treatment for 24 and 48 h. Our results indicate that the tested …
Photocatalysis Of Formaldehyde In The Aqueous Phase Over Zno/Diatomite Nanocomposite, Reza Darvishi Cheshmeh Soltani, Alireza Khataee, Masumeh Mashayekhi, Mahdi Safari
Photocatalysis Of Formaldehyde In The Aqueous Phase Over Zno/Diatomite Nanocomposite, Reza Darvishi Cheshmeh Soltani, Alireza Khataee, Masumeh Mashayekhi, Mahdi Safari
Turkish Journal of Chemistry
In the present study, ZnO nanostructures were synthesized and immobilized on the surface of diatomite via a simple sonochemical method for the photocatalytic degradation of formaldehyde in the aqueous phase. The characterization of as-prepared ZnO/diatomite nanocomposite was carried out by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The photocatalysis of formaldehyde was favored at neutral pH. At a ZnO to diatomite ratio of 0.3, increasing the photocatalyst dosage from 0.2 to 1.5 g/L resulted in increasing the photocatalytic removal of formaldehyde from 37.51% to 88.05%. At a formaldehyde concentration of 100 mg/L, …
Synthesis And Application Of Polyvinylimidazole-Based Bronsted Acidic Ionic Liquid Grafted Silica As An Efficient Heterogeneous Catalyst In The Preparation Of Quinoxaline Derivatives, Bahman Tamami, Alireza Sardarian, Elaheh Ataollahi
Synthesis And Application Of Polyvinylimidazole-Based Bronsted Acidic Ionic Liquid Grafted Silica As An Efficient Heterogeneous Catalyst In The Preparation Of Quinoxaline Derivatives, Bahman Tamami, Alireza Sardarian, Elaheh Ataollahi
Turkish Journal of Chemistry
Two types of polymer-grafted silica based on polyvinylimidazole Bronsted acidic ionic liquids were prepared and used as new heterogeneous catalysts for the preparation of pharmaceutically important quinoxaline derivatives. These catalysts were characterized by thermogravimetric analysis, FT-IR spectroscopy, and titration. They could be recycled without considerable loss in their catalytic activity. High efficiency of the catalysts along with short reaction times, high yields, easy purification, recyclability, and simple procedure are among the advantages of these catalytic systems.
An Efficient One-Pot, Three-Component Synthesis Of 6-Cyano-Hexahydro-4$H$-Thieno[3',2':5,6]Pyrimido[1,2-$A$]Quinoline-2-Carboxylates And Their Spiro Derivatives From $\Beta $-Enaminones, Said Ahmed Soliman Ghozlan, Doaa Mohmed Abdelmoniem, Amr Mohmed Abdelmoniem, Ismail Abdelshafy Abdelhamid
An Efficient One-Pot, Three-Component Synthesis Of 6-Cyano-Hexahydro-4$H$-Thieno[3',2':5,6]Pyrimido[1,2-$A$]Quinoline-2-Carboxylates And Their Spiro Derivatives From $\Beta $-Enaminones, Said Ahmed Soliman Ghozlan, Doaa Mohmed Abdelmoniem, Amr Mohmed Abdelmoniem, Ismail Abdelshafy Abdelhamid
Turkish Journal of Chemistry
A simple and efficient one-pot synthesis of novel thieno[3',2':5,6]pyrimido[1,2-a]quinoline-2-carboxylates (5a-d) and their spirooxindole derivatives (12a-d) was accomplished. Thus, the Michael addition reaction of the cyclic $\beta $-enaminone 3 with the corresponding $\alpha ,\beta $-unsaturated nitrile derivatives 4a-d in refluxing EtOH in the presence of piperidine afforded 5a-d in good yields. On the other hand, spirooxindole derivatives 12a-d were synthesized by the reaction of cyclic $\beta $-enaminone 3 with the corresponding 3-cyanomethylidene-2-oxoindoles 11a-d in refluxing EtOH.
Synthesis, And Prediction Of Molecular Properties And Antimicrobial Activity Of Some Acylhydrazones Derived From $N$-(Arylsulfonyl)Methionine, Esra Tatar, Sevi̇l Şenkardeş, Hasan Erdi̇nç Selli̇tepe, Şükri̇ye Güni̇z Küçükgüzel, Şengül Alpay Karaoğlu, Ari̇f Bozdeveci̇, Erik De Clercq, Christophe Pannecouque, Tai̇bi̇ Ben Hadda, İlkay Küçükgüzel
Synthesis, And Prediction Of Molecular Properties And Antimicrobial Activity Of Some Acylhydrazones Derived From $N$-(Arylsulfonyl)Methionine, Esra Tatar, Sevi̇l Şenkardeş, Hasan Erdi̇nç Selli̇tepe, Şükri̇ye Güni̇z Küçükgüzel, Şengül Alpay Karaoğlu, Ari̇f Bozdeveci̇, Erik De Clercq, Christophe Pannecouque, Tai̇bi̇ Ben Hadda, İlkay Küçükgüzel
Turkish Journal of Chemistry
A series of 38 new acylhydrazones [3-40], derived from (2$S)$-4-(methylsulfanyl)-2-[[(4-methylphenyl)sulfonyl] amino]butanoic acid hydrazide [2], were synthesized and evaluated for their anti-HIV and antimicrobial activity with the further aim to develop acylhydrazones carrying an amino acid side chain. All tested compounds possess stronger activity against gram (+) bacteria. Compound 23 was found active against methicillin-resistant Staphylococcus aureus (MRSA) with a MIC value of 3.9 $\mu $g/mL. The MIC value of compound 30 against Enterococcus faecalis, Listeria monocytogenes, and Bacillus cereus was 8 $\mu $g/mL. A computational study for prediction of ADME and drug-like properties (solubility, drug-likeness, and drug score) as well …
Comparative Density Functional Study Of Antioxidative Activity Of The Hydroxybenzoic Acids And Their Anions, Zoran Markovic, Jelena Djorovic, Jasmina M. Dimitric Markovic, Radomir Biocanin, Dragan Amic
Comparative Density Functional Study Of Antioxidative Activity Of The Hydroxybenzoic Acids And Their Anions, Zoran Markovic, Jelena Djorovic, Jasmina M. Dimitric Markovic, Radomir Biocanin, Dragan Amic
Turkish Journal of Chemistry
Hydroxybenzoic acids (HBAs) and their anions play an important role in the food and pharmaceutical industries because of their antioxidant activity. In this study, we examined the mechanisms of the free radical scavenging action of HBAs and their anions using density functional theory (DFT) methods. Reaction enthalpies related to the mechanisms of free radical scavenging by the investigated species were calculated by DFT methods in water, DMSO, pentylethanoate, and benzene. Hydrogen atom transfer (HAT) is a preferred reaction pathway in benzene, while sequential proton loss electron transfer (SPLET) is a predominant reaction pathway in polar solvents, water, and DMSO for …
Ecofriendly One-Pot Synthesis And Antiviral Evaluation Of Novel Pyrazolyl Pyrazolines Of Medicinal Interest, Sobhi Gomha, Magda Abdalla, Mohamad Abd El-Aziz, Nany Serag
Ecofriendly One-Pot Synthesis And Antiviral Evaluation Of Novel Pyrazolyl Pyrazolines Of Medicinal Interest, Sobhi Gomha, Magda Abdalla, Mohamad Abd El-Aziz, Nany Serag
Turkish Journal of Chemistry
Ethyl 3-acetyl-1,5-diphenyl-1$H$-pyrazole-4-carboxylate reacts with a variety of arylaldehydes by grinding method in the presence of a catalytic amount of sodium hydroxide at ambient temperature to give the respective chalcones. The latter compounds react also by grinding method with nitrogen nucleophiles such as hydrazine hydrate, phenylhydrazine, and thiosemicarbazide to afford the corresponding pyrazol-3-yl pyrazolines. A series of 6-pyrazolylpyrimidine-2-thione derivatives were prepared by reaction of the above chalcones with thiourea by grinding method in the presence of a catalytic amount of sodium hydroxide at room temperature. In addition, 7-pyrazolylpyridopyrimidine-3-thione was prepared by reaction of chalcone with 6-aminothiouracil. All the newly synthesized compounds …
Visible Light Photocatalysis Of A Textile Dye Over Zno Nanostructures Covered On Natural Diatomite, Reza Darvishi Cheshmeh Soltani, Zohreh Haghighat
Visible Light Photocatalysis Of A Textile Dye Over Zno Nanostructures Covered On Natural Diatomite, Reza Darvishi Cheshmeh Soltani, Zohreh Haghighat
Turkish Journal of Chemistry
In the present study, ZnO nanostructures were ultrasonically synthesized and immobilized on the surface of diatomite and used for visible light photocatalysis of Acid Red 88 (AR88) in the aqueous phase. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses were employed for characterization of the samples. The process was optimized via response surface methodology (RSM) on the basis of central composite design (CCD). Based on numerical optimization, for the maximized color removal of 96% the initial dye concentration, the catalyst dosage, the reaction time, and the initial pH were 13 mg/L, 1.5 g/L, 85 min, and 4, respectively. The …
Experimental And Theoretical Approaches For Structural And Mechanical Properties Of Novel Side Chain Lcp-Pp Graft Coproducts, Sedat Çeti̇n, Behi̇ye Öztürk Şen, Uğur Soykan, Eli̇f Esra Firat, Gürcan Yildirim
Experimental And Theoretical Approaches For Structural And Mechanical Properties Of Novel Side Chain Lcp-Pp Graft Coproducts, Sedat Çeti̇n, Behi̇ye Öztürk Şen, Uğur Soykan, Eli̇f Esra Firat, Gürcan Yildirim
Turkish Journal of Chemistry
The monomers p-biphenyloxycarbonylphenyl acrylate (BPCPA) and p-biphenyloxycarbonylphenyl methacrylate (BPCPMA) were synthesized by the reaction of p-acryloyloxybenzoyl chloride and p-methacryloyloxybenzoyl chloride with 4-hydroxybiphenyl, respectively, and polymerized by bulk polymerization in vacuum by using dicumyl peroxide. The graft copolymerization of the monomers onto polypropylene were carried out by bulk melt polymerization at 170 $^{\circ}$C with various concentration levels of the monomers and the initiator in reaction mixtures. The content of monomers in their graft coproducts increased with monomer-initiator percentage in the reaction medium. The graft coproducts were characterized by several available experimental techniques including differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared …
Prostereoisomerism And Biological Activity: Possible Implications For Drug Design, Sosale Chandrasekhar
Prostereoisomerism And Biological Activity: Possible Implications For Drug Design, Sosale Chandrasekhar
Turkish Journal of Chemistry
Prostereoisomerism (PIM), representing a subgroup within the achiral class of molecules, is manifested in a chiral environment. Although this is regardless of the orientation of the prostereoisomeric (PIC) molecule, PIM is manifested most emphatically in relation to a chiral surface (`two-dimensional chirality'). Then PIM is tantamount to `de facto chirality' as attachment of the PIC molecule to the surface leads to diastereomeric possibilities (cf. Ogston's hypothesis). Furthermore, the formation of host--guest complexes requires a steric complementarity between the component molecules. The fact that the weak dispersive forces involved therein require an optimum distance implies a `snugness of fit' criterion. This …
Preparation And Characterization Of Zno/Mmt Nanocomposite For Photocatalytic Ozonation Of A Disperse Dye, Alireza Khataee, Murat Kiranşan, Semra Karaca, Samira Arefi- Oskoui
Preparation And Characterization Of Zno/Mmt Nanocomposite For Photocatalytic Ozonation Of A Disperse Dye, Alireza Khataee, Murat Kiranşan, Semra Karaca, Samira Arefi- Oskoui
Turkish Journal of Chemistry
ZnO was immobilized on the montmorillonite (MMT) to synthesize ZnO/MMT nanocomposite. Physicochemical properties of the as-synthesized nanocomposite were determined using X-ray diffraction, scanning electron microscopy, transmission electron microscope, Fourier transform infrared spectroscopy, N$_{2}$ adsorption/desorption, and point of zero charge pH (pH$_{pzc})$ analysis. The performance of the prepared ZnO/MMT nanocomposite was examined for the photocatalytic ozonation of Disperse Red 54 (DR54) and the highest decolorization efficiency (88.75{\%} after 60 min of reaction time) was the result for the mentioned process compared to adsorption, single ozonation, catalytic ozonation, and photolysis. The influence of various operational parameters including initial dye concentration, catalyst concentration, …
Preparation, Characterization, And Adsorption Studies Of Core@Shell Sio$_{2}$@Ceo$_{2}$ Nanoparticles: A New Candidate To Remove Hg(Ii) From Aqueous Solutions, Ali̇ İmran Vai̇zoğullar, Ahmet Balci, İbrahi̇m Kula, Mehmet Uğurlu
Preparation, Characterization, And Adsorption Studies Of Core@Shell Sio$_{2}$@Ceo$_{2}$ Nanoparticles: A New Candidate To Remove Hg(Ii) From Aqueous Solutions, Ali̇ İmran Vai̇zoğullar, Ahmet Balci, İbrahi̇m Kula, Mehmet Uğurlu
Turkish Journal of Chemistry
SiO$_{2}$ supported core@shell nanoparticles (CSNs) have recently attracted great attention due to their unique, tunable, optical, photocatalytic, and higher adsorption properties. In this study, SiO$_{2}$@CeO$_{2}$~CSNs were synthesized using a chemical precipitation technique and characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) analysis. XRD analysis showed that SiO$_{2\, }$particles were the core while CeO$_{2}$ particles were the shell. It was seen as a new band at 961 cm$^{-1}$ of the oxygen bridge between Si and Ce atoms from FT-IR results; SiO$_{2}$ and CSNs were spherical (0.5--0.6 $\mu $m) from SEM and …
The Mediatory Activity Of Meso-Tetraphenylporphyrin Iron(Iii) Complex Immobilized In Nafion Film On A Pt Electrode In The Oxidation Of 1,2- And 1,4-Hydroquinones, Slawomir Domagala, Slawomira Skrzypek, Michal Cichomski, Andrzej Leniart
The Mediatory Activity Of Meso-Tetraphenylporphyrin Iron(Iii) Complex Immobilized In Nafion Film On A Pt Electrode In The Oxidation Of 1,2- And 1,4-Hydroquinones, Slawomir Domagala, Slawomira Skrzypek, Michal Cichomski, Andrzej Leniart
Turkish Journal of Chemistry
This paper presents the results of an investigation of the properties of a modified platinum electrode with meso-tetraphenylporphyrin iron(III) complex immobilized in Nafion film and its catalytic activity in the electrochemical oxidation of selected hydroquinone and catechol derivatives. The redox activity of iron complexes of porphyrins was characterized in aqueous solutions of perchloric acid by means of cyclic voltammetry and differential pulse voltammetry. Both the increase in the anodic peak currents of the investigated compounds during oxidation on the platinum electrode modified with meso-tetraphenylporphyrin iron(III) complex immobilized in Nafion film (FeTPhP/Nafion/Pt) and the considerable decrease in the cathodic peak currents …
Synthesis Of Novel Thiazolylpyrazoline Derivatives And Evaluation Of Their Antimicrobial Activities And Cytotoxicities, Aouatef Tabbi, Zafer Asim Kaplancikli, Dahmane Tebbani, Leyla Yurttaş, Zerri̇n Cantürk, Özlem Atli, Merve Baysal, Gülhan Turan Zitouni
Synthesis Of Novel Thiazolylpyrazoline Derivatives And Evaluation Of Their Antimicrobial Activities And Cytotoxicities, Aouatef Tabbi, Zafer Asim Kaplancikli, Dahmane Tebbani, Leyla Yurttaş, Zerri̇n Cantürk, Özlem Atli, Merve Baysal, Gülhan Turan Zitouni
Turkish Journal of Chemistry
Several novel thiazolylpyrazoline derivatives were synthesized by reacting substituted 3,5-diaryl-1-thiocarba\-moyl-2-pyrazolines with phenacylbromides. The structures of the synthesized compounds were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, and MS spectral data. Their antimicrobial activities against Staphylococcus aureus(ATCC-25923), Enterococcus faecalis} (ATCC-29212), Enterococcus faecalis (ATCC-51922), Listeria monocytogenes (ATCC-1911), Klebsiella pneumoniae (ATCC-700603), Pseudomonas aeruginosa (ATCC-27853), Escherichia coli (ATCC-35218), Escherichia coli (ATCC-25922), Candida albicans (ATCC-90028), Candida glabrata (ATCC-90030), Candida krusei (ATCC-6258), and Candida parapsilosis (ATCC-22019) were investigated. The compounds were also studied for their cytotoxic effects using a MTT assay. Compound 7c showed the highest antimicrobial activity, possessing the same potential as chloramphenicol against K. …
Isoquinoline-Substituted Triazole And Pyran Derivatives: Synthesis And Computational Studies, Duygu Yeni̇dede, Selçuk Gümüş, Ayşegül Gümüş
Isoquinoline-Substituted Triazole And Pyran Derivatives: Synthesis And Computational Studies, Duygu Yeni̇dede, Selçuk Gümüş, Ayşegül Gümüş
Turkish Journal of Chemistry
The one-pot synthesis of novel 1,4-disubstituted 1,2,3-triazoles from isoquinoline-substituted homopropargyl alcohol backbone is described (42%-88% yields). A ring closing metathesis reaction and an intramolecular Pauson-Khand reaction of enyne system derived from a homopropargyl alcohol backbone to afford the corresponding isoquinoline-substituted dihydropyran and cyclopentenone-pyran, respectively, are also described (54% and 78% yields). Information about the structural, electronic, and physico-chemical properties of the novel compounds, obtained by density functional theory application, is also reported.
Characterization Of An Al$^{3+}$-Selective Fluorescent Probe Based On A Benzoyl Hydrazine Derivative And Its Application In Cell Imaging, Yuxiang Ji, Chunwei Yu, Shaobai Wen, Jun Zhang
Characterization Of An Al$^{3+}$-Selective Fluorescent Probe Based On A Benzoyl Hydrazine Derivative And Its Application In Cell Imaging, Yuxiang Ji, Chunwei Yu, Shaobai Wen, Jun Zhang
Turkish Journal of Chemistry
A fluorescent probe based on benzoyl hydrazine was synthesized and characterized as an Al$^{3+}$-selective fluorescent probe. This probe showed good selectivity towards Al$^{3+\, }$compared to other common ions. Under optimized experimental conditions, the probe exhibited a linear dynamic response for Al$^{3+}$ from 5.0 $\times $ 10$^{-7}$ to 4.5 $\times $ 10$^{-6}$ M with a detection limit of 1.3 $\times $ 10$^{-7}$ M in ethanol-water solution (9:1, v:v, pH 6.8, 20 mM HEPES). Furthermore, it was used for imaging of Al$^{3+}$ in living cells with satisfying results.
Newly Synthesized Furanoside-Based Nhc Ligands For The Arylation Of Aldehydes, Serpi̇l Deni̇zalti, Fatma Çeti̇n Telli̇, Seli̇n Yildiran, Azi̇ze Yeşi̇m Salman, Beki̇r Çeti̇nkaya
Newly Synthesized Furanoside-Based Nhc Ligands For The Arylation Of Aldehydes, Serpi̇l Deni̇zalti, Fatma Çeti̇n Telli̇, Seli̇n Yildiran, Azi̇ze Yeşi̇m Salman, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
New furanoside-based NHC precursor salts (2) were synthesized using amino alcohols from the chloralose derivatives of glucose (a), galactose (b), and mannose (c). The novel compounds were fully characterized by $^{1}$H NMR, $^{13}$C NMR, and elemental analyses. The catalytic activities of these salts were tested in the arylation of aldehydes as catalysts that were generated in situ from [RhCl(COD)]$_{2}$. In addition, 2a was converted to the rhodium complex 3a in order to compare the results obtained in situ. The newly synthesized compounds were very efficient in terms of yield; nevertheless they did not exhibit a chiral induction.
Comparison Of Influence Of Nanomaterials On A Glassy Carbon Paste Electrode-Based Bioanode In Biofuel Cells, Sema Aslan, Murat Tutum, Yudum Tepeli̇, Ülkü Anik
Comparison Of Influence Of Nanomaterials On A Glassy Carbon Paste Electrode-Based Bioanode In Biofuel Cells, Sema Aslan, Murat Tutum, Yudum Tepeli̇, Ülkü Anik
Turkish Journal of Chemistry
This paper presents a comparative study of nanomaterial modified glassy carbon paste electrodes (GCPEs) used as bioanodes in enzymatic biofuel cells. The developed bioanode electrodes were obtained by modification of composite GCPEs with glucose oxidase (GOx) and different nanomaterials like manganese(IV) oxide nanoparticle (MnO$_{2}$ np) and aluminum titanate (Al$_{2}$O$_{3}$-TiO$_{2})$ bimetallic nanostructure. These nanostructures were utilized in a GCPE-based enzymatic bioanode construction for the first time. P-benzoquinone mediator was used for the electron transfer between enzyme redox center and bioanode electrode where glucose analyte was used as substrate. A laccase-modified plain GCPE was used as biocathode electrode. Then these electrodes were …
Ag(I) Complexes Of Benzimidazol-2-Ylidene Ligands: A Study Of Catalytic Efficiency Towards Three-Component Coupling Reactions, Rafet Kilinçarslan, Nai̇m Sadiç, Beki̇r Çeti̇nkaya
Ag(I) Complexes Of Benzimidazol-2-Ylidene Ligands: A Study Of Catalytic Efficiency Towards Three-Component Coupling Reactions, Rafet Kilinçarslan, Nai̇m Sadiç, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
The $N$-heterocyclic carbene (NHC)--Ag(I) complexes 3a-c were synthesized from benzimidazolium chlorides (2a-c = NHC.HCl), incorporating benzyl derivatives and a 2-methoxyethyl group (a: $^{3}$N = 2,4,6-trimethylbenzyl; b: $^{3}$N = 2,3,5,6-tetramethylbenzyl; c: $^{3}$N = pentamethylbenzyl). The compounds were characterized by spectroscopic and elemental analyses. The synthesized NHC-Ag(I) complexes (3a-c) were tested as catalysts for the catalytic three-component coupling reaction of aldehyde, alkyne, and amine to propargylamines in various solvents. All complexes were active catalysts for catalytic three-component coupling reactions with good yields under neat and mild conditions (after 4 h, yields of up to 94%).
Speciation Of Inorganic Selenium By Solid Phase Extraction Using Nanozirconium Oxide/Boron Oxide Composite Material, Hakan Erdoğan, Özcan Yalçinkaya, Ali̇ Rehber Türker
Speciation Of Inorganic Selenium By Solid Phase Extraction Using Nanozirconium Oxide/Boron Oxide Composite Material, Hakan Erdoğan, Özcan Yalçinkaya, Ali̇ Rehber Türker
Turkish Journal of Chemistry
The speciation and preconcentration of selenium were carried out by solid phase extraction using nanozirconium oxide/boron oxide (ZrO$_{2}$/B$_{2}$O$_{3})$. Electrothermal atomic absorption spectrometry (ETAAS) was used for detection. This preconcentration and/or speciation method depends on the retention of Se(IV) ions selectively as its ammonium pyrrolidine dithiocarbamate (APDC) complex on the sorbent. The effects of pH, flow rate, and volume of sample solution and eluent type were investigated for determining the optimum preconcentration and speciation conditions. The effects of other ions that may interfere with the determination and speciation of selenium were also investigated. Moreover, the analytical performance criteria of the method …
An Indirect Model For Sintering Thermodynamics, Yüksel Sarikaya, Müşerref Önal
An Indirect Model For Sintering Thermodynamics, Yüksel Sarikaya, Müşerref Önal
Turkish Journal of Chemistry
A model was proposed and used to calculated the changes in enthalpy $(\Delta H^{o})$, entropy $(\Delta S^{o}),$ and Gibbs energy $(\Delta G^{o})$, as well as equilibrium constant $(K)$ relating to the sintering of alumina compacts. Specific nanopore volume $(V)$ of the compacts was assumed as a thermodynamic variable. A hypothetical equilibrium constant $(K_{h})$ and corresponding Gibbs energy $(\Delta G_{h}^{o})$ were calculated depending on the $V$ value measured after each sintering. The thermodynamic relationships with the SI units were respectively evaluated for the initial-stage $(i)$ sintering between 1000 and 1200 $^{\circ}$C and final-stage $(f)$ sintering between 1200 and 1600 $^{\circ}$C in …
Zr(Iv) Complexes Of Some Heterocyclic Ligands: Synthesis, Characterization, And Ethylene Polymerization Activity, Hamdi Ali Elagab
Zr(Iv) Complexes Of Some Heterocyclic Ligands: Synthesis, Characterization, And Ethylene Polymerization Activity, Hamdi Ali Elagab
Turkish Journal of Chemistry
Thirty-one complexes of bis-(benzimidazole, benzothiazole, and benzoxazole) compounds with Zr(IV) metal centers were synthesized, characterized, activated with methylaluminoxane (MAO), and then tested for catalytic ethylene polymerization. The activities of the various catalysts were found to be functions of the heteroatoms in the ligand frameworks and the structure around the active metal center. The highest activity was obtained with 38/MAO (424 kg E/mol cat. h). The produced polyethylenes showed high molecular weights (41/MAO, 1.9 $\times$ 10$^{6}$ g/mol) and broad molecular weight distributions (38/MAO, M$_{w}$ = 9.64 $\times $ 10$^{5}$ g/mol, PD = 23). This could result from different interactions of the …
Bismuth(Iii)-Sio$_{2}$ Catalyzed Synthesis Of Polysubstituted Imidazoles With The Participation Of Azaaryl Derivatives Of Aniline In Four-Component Reactions, Zarrin Ghasemi, Ziba Zakeri, Maryam Allahvirdinesbat
Bismuth(Iii)-Sio$_{2}$ Catalyzed Synthesis Of Polysubstituted Imidazoles With The Participation Of Azaaryl Derivatives Of Aniline In Four-Component Reactions, Zarrin Ghasemi, Ziba Zakeri, Maryam Allahvirdinesbat
Turkish Journal of Chemistry
A series of novel polyaromatic derivatives of imidazole were synthesized by Bi(III) nitrate-SiO$_{2}$ catalyzed four-component reactions of benzil, ammonium acetate, aromatic aldehydes, and $N$-heterocyclic derivatives of aniline under solvent-free conditions.
Mn-Doped Zns Quantum Dots As A Room-Temperature Phosphorescent Probe For Analysis Of Glutamic Acid In Foodstuffs, Hayri̇ye Eda Şatana Kara, Burak Demi̇rhan, Buket Er Demi̇rhan
Mn-Doped Zns Quantum Dots As A Room-Temperature Phosphorescent Probe For Analysis Of Glutamic Acid In Foodstuffs, Hayri̇ye Eda Şatana Kara, Burak Demi̇rhan, Buket Er Demi̇rhan
Turkish Journal of Chemistry
L-cysteine-capped Mn-doped ZnS quantum dots (QDs) were used for the determination of glutamic acid in foodstuffs. This method is based on measurement of the quenching of the phosphorescence intensity of the QDs after interacting with glutamic acid. A linear response was observed from 50 to 500 ng mL$^{-1}$ glutamic acid with a limit of detection of 6.79 ng mL$^{-1}$. Room temperature phosphorescence (RTP) intensity of the QDs was quenched rapidly upon the addition of the quencher and the reaction reached equilibrium within 2 min. The quenching mechanism of phosphorescence of Mn-doped ZnS QDs by glutamic acid is dynamic and the …
Production, Purification, And Characterization Of A Thermo-Alkali Stable And Metal-Tolerant Carboxymethylcellulase From Newly Isolated Bacillus Methylotrophicus Y37, Yonca Duman, Yonca Yüzügüllü Karakuş, Arzu Sertel, Fi̇kri̇ye Polat
Production, Purification, And Characterization Of A Thermo-Alkali Stable And Metal-Tolerant Carboxymethylcellulase From Newly Isolated Bacillus Methylotrophicus Y37, Yonca Duman, Yonca Yüzügüllü Karakuş, Arzu Sertel, Fi̇kri̇ye Polat
Turkish Journal of Chemistry
A carboxymethylcellulose (CMC)-degrading bacterium was isolated from soil, identified as Bacillus methylotrophicus according to the physiological properties and analyses of 16S rRNA and a partial sequence of the gyrase A (gyrA) gene, and named as B. methylotrophicus Y37. The CMCase enzyme was purified to homogeneity by 20.4-fold with 21.73% recovery using single-step hydrophobic interaction chromatography and biochemically characterized. CMCase showed a molecular weight of approximately 50 kDa as determined by SDS-PAGE. The activity profile of the CMCase enzyme exhibited optimum activity at 45 $^{\circ}$C and pH 5.0. The activity was highly stable at alkaline pH levels. More than 90% of …
Speciation Of Trace Metals And Metalloids By Solid Phase Extraction With Spectrometric Detection: A Critical Review, Ali̇ Rehber Türker
Speciation Of Trace Metals And Metalloids By Solid Phase Extraction With Spectrometric Detection: A Critical Review, Ali̇ Rehber Türker
Turkish Journal of Chemistry
Considerable interest is continuing to be shown in the speciation of metals, metalloids, and organometals due to the dependence of their toxicity and mobility on their chemical form. This review focuses on the speciation analysis of metals, metalloids, and organometals by solid phase extraction before spectrometric detection, and all aspects of analytical speciation such as determination of oxidation states and organometallic compounds. Some applications of speciation of metals and metalloids are also presented and discussed in this review. Fractionation, which is used sometimes as speciation, and chromatographic detection are not discussed. This review covers approximately the last four years (2012-March …
Synthesis, ($E)$/($Z)$-Isomerization, And Dna Binding, Antibacterial, And Antifungal Activities Of Novel Oximes And $O$-Substituted Oxime Ethers, Hati̇ce Başpinar Küçük, Ayşe Sergüzel Yusufoğlu, Leyla Açik, Betül Aydin, Leyla Arslan
Synthesis, ($E)$/($Z)$-Isomerization, And Dna Binding, Antibacterial, And Antifungal Activities Of Novel Oximes And $O$-Substituted Oxime Ethers, Hati̇ce Başpinar Küçük, Ayşe Sergüzel Yusufoğlu, Leyla Açik, Betül Aydin, Leyla Arslan
Turkish Journal of Chemistry
A series of novel positional oximes (2a-2d), $O$-methyl oxime ethers (3a-3d), and $O$-benzyl oxime ethers (4a-4d) were synthesized in high yields starting from their corresponding methyl 3-, 4-, 6-, and 13-keto tetradecanoates. The synthesized compounds were characterized by $^{1}$H NMR, $^{13}$C NMR, FT-IR, mass, and elemental analyses for their structures and $(E)$/$(Z)$ isomerizations. Their DNA binding abilities were investigated in vitro by agarose gel electrophoresis. The antibacterial and antifungal activities were tested also in vitro against eleven bacterial strains and three fungal strains. The relationship between the structure and the mentioned biological activities was discussed. Compound 2a showed good antibacterial …
Chromate Surface-Imprinted Silica Gel Sorbent For Speciation Of Cr In Surface Waters, Mariya Mitreva, Ivanka Dakova, Tanya Yordanova, Irina Karadjova
Chromate Surface-Imprinted Silica Gel Sorbent For Speciation Of Cr In Surface Waters, Mariya Mitreva, Ivanka Dakova, Tanya Yordanova, Irina Karadjova
Turkish Journal of Chemistry
This study is focused on the synthesis of chromate anion imprinted sorbent supported on silica gel for nonchromatographic Cr speciation in surface waters. The preparation procedure is based on grafting of 3-methyl-1-trimethoxysilylpropylimidazolium, preliminarily coordinated to CrO$_{4}^{2-}$ as a template ion, onto the surface of silica gel. Sorption and desorption characteristics of surface-imprinted sorbent toward Cr(III) and Cr(VI) were examined by batch solid-phase extraction. An excellent separation of Cr(VI), selectively retained on the sorbent, from Cr(III) remained in the solution, was achieved at pH 2-3 for 20 min. A freshly prepared mixture of ascorbic acid and nitric acid was selected as …