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Full-Text Articles in Physical Sciences and Mathematics
Antioxidant Potential And Secondary Reactivity Of Bis$\{$Diphenyl(2-Pyridyl)Phosphino$\}$Copper(Ii) Complex, Ezzat Khan, Adnan Shahzad, Muhammad Nawaz Tahir, Awal Noor
Antioxidant Potential And Secondary Reactivity Of Bis$\{$Diphenyl(2-Pyridyl)Phosphino$\}$Copper(Ii) Complex, Ezzat Khan, Adnan Shahzad, Muhammad Nawaz Tahir, Awal Noor
Turkish Journal of Chemistry
Copper-based complexes with the general formulas [Cu(L)$_{2}$]Cl$_{2}$ (1) and [Cu$_{2}$L$_{2}$($\mu_{2}$-L)$\mu_{2-}$Cl$_{2}$] (2) and a mixed-ligand anionic complex [Cu(L)$_{2}$dedtc][LCl] (3b), where L= diphenyl(2-pyridyl)phosphine and dedtc = diethyldithiocarbamate, were synthesized and structurally characterized. X-ray analysis revealed that the coordination environment around the copper atom in complexes 1-3 is distorted tetrahedral. In monomeric complexes 1 and 3b both diphenyl(2-pyridyl) phosphine ligands are monodentate and are coordinated through the P-atom. In complex 3b two phosphine ligands are attached to copper through the P-atom. The third phosphine ligand acts as a bridged ligand, coordinated to the metal centers through the P-atom and N-atom. Complexes 1 and …
The Interaction Between A Zinc(Ii) Phthalocyanine Compound Bearing Octakis Phenoxyacetamide Substituents And Calf Thymus Dna, Ali̇ Arslantaş, Mehmet Sali̇h Ağirtaş
The Interaction Between A Zinc(Ii) Phthalocyanine Compound Bearing Octakis Phenoxyacetamide Substituents And Calf Thymus Dna, Ali̇ Arslantaş, Mehmet Sali̇h Ağirtaş
Turkish Journal of Chemistry
In this study, a zinc(II) phthalocyanine compound (PcZn) substituted with octakis phenoxyacetamide was synthesized and characterized. Calf thymus DNA (CT-DNA) was used to determine the DNA binding properties of the zinc(II) phthalocyanine compound. This interaction of CT-DNA with PcZn was investigated using electronic absorption spectra, emission spectroscopy, a thermal melting temperature study, cyclic voltammetry, and viscosity measurements in a Tris-HCl buffer solution at a pH of 7.2. The findings showed that zinc(II) phthalocyanine interacts with calf thymus DNA via partial intercalative binding mechanisms. In addition to the techniques above, a gel electrophoresis study was also carried out to verify the …
A New Cocrystal Explosive Trinitrotoluene (Tnt):1-Amino-4-Bromonaphthalene With Reduced Sensitivity, Ni̇lgün Şen
A New Cocrystal Explosive Trinitrotoluene (Tnt):1-Amino-4-Bromonaphthalene With Reduced Sensitivity, Ni̇lgün Şen
Turkish Journal of Chemistry
A 1:1 cocrystal of TNT and 1-amino-4-bromonaphthalene was prepared via solvent evaporation. The structure of the cocrystal was determined via single-crystal and powder X-ray diffraction. Crystal structure determination studies indicated that the main mechanism of cocrystallization originates from the intermolecular hydrogen bonding (amino-nitro), halogen bonding, and $\pi -\pi $ stacking. Investigation of intermolecular interactions by Hirshfeld surface and fingerprint plot analysis revealed that the structures were stabilized by H...H, O...H, C...C ($\pi -\pi )$ and Br...O interactions. Hirshfeld surfaces showed that these weak interactions were significant for crystal packing. We analyzed the crystal packing and showed how this may influence …
Synthesis And Biological Evaluation Of Quinoline-Triazole And Quinolone-Triazole Conjugates, Ayşegül Gümüş, Veysi̇ Okumuş
Synthesis And Biological Evaluation Of Quinoline-Triazole And Quinolone-Triazole Conjugates, Ayşegül Gümüş, Veysi̇ Okumuş
Turkish Journal of Chemistry
One-pot synthesis of novel quinoline- and quinolone-substituted 1,2,3-triazoles has been performed from the key intermediates, quinoline- and quinolone-substituted propargyl derivatives 1-3 (48%-88% yields). The antioxidant properties of the newly synthesized compounds, 1a-1c, 2a-2c, and 3a-3c, were evaluated by monitoring DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging abilities, metal chelating effects, and reducing power. The scavenging effects of compounds on the free radical decreased in the order of 3b$>$ 3a$>$ 1b} and were found to be 36.3%, 34.9%, and 27.6% at the concentration of 500 $\mu $g/mL, respectively. All of the compounds showed low chelating capacity. Furthermore, the antibacterial activity was studied …
Synthesis Of 2-Substituted 8-Propargyloxyquinoline Derivatives And Determination Of Their Antioxidant, Antibacterial, And Dna Binding Activities, Ayşegül Gümüş, Veysi̇ Okumuş, Selçuk Gümüş
Synthesis Of 2-Substituted 8-Propargyloxyquinoline Derivatives And Determination Of Their Antioxidant, Antibacterial, And Dna Binding Activities, Ayşegül Gümüş, Veysi̇ Okumuş, Selçuk Gümüş
Turkish Journal of Chemistry
2-Substituted 8-propargyloxyquinoline derivatives have been synthesized from 2-substituted-8-hydroxyquinolines by O-propargylation method (30%-98% yields). The newly synthesized compounds were tested for in vitro antioxidant activities such as DPPH radical scavenging, ferrous chelating, and reducing power activities. The maximum radical scavenging (46.5%) and reducing power activities were obtained from 1 and maximum ferrous chelating effect was obtained from 6 (72.1%) at the concentration of 500 $\mu $g/mL. To indicate DNA binding activity of the complexes calf thymus DNA was used. The compounds were also evaluated for their antimicrobial activity against three gram-positive and three gram-negative bacteria. Compounds 3 and 5 exhibited antibacterial …
Synthesis, Characterization, And Application Of Monodisperse Poly L-Dopa Microspheres, Azadeh Havasian, Elham Heydaripour, Mohammad Reza Nateghi, Mohammad Hossein Mosslemin, Forough Kalantari-Fotouh
Synthesis, Characterization, And Application Of Monodisperse Poly L-Dopa Microspheres, Azadeh Havasian, Elham Heydaripour, Mohammad Reza Nateghi, Mohammad Hossein Mosslemin, Forough Kalantari-Fotouh
Turkish Journal of Chemistry
In this study, 3,4-dihydroxy-L-phenylalanine (L-Dopa) was solvothermally polymerized to monodisperse microspheres 1 $\mu $m in diameter. Polymerization was carried out in dimethylformamide containing appropriate amounts of urea and L-Dopa at 120 $^{\circ}$C for 24 h. Synthesis of the polymer in basic aqueous solution under hydrothermal conditions or via conventional heating resulted in the formation of bulky powders including irregularly shaped particles of the polymer. The morphologies of the synthesized polymers were characterized by scanning electron microscopy (SEM). The microspheres synthesized by solvothermal method (with $\sim $1 $\mu $m average diameter) were clearly observable in SEM micrographs. The thermal stability of …
Synthetic Strategies Towards The Carbenoid Reactions Of $\Alpha ,\Beta $-Acetylenic Carbonyls, Füsun Şeyma Kişkan, Emre Özgüz, Olcay Anaç, Nurdan Tarakçi, Gökçe Merey
Synthetic Strategies Towards The Carbenoid Reactions Of $\Alpha ,\Beta $-Acetylenic Carbonyls, Füsun Şeyma Kişkan, Emre Özgüz, Olcay Anaç, Nurdan Tarakçi, Gökçe Merey
Turkish Journal of Chemistry
Catalytic reactions of $\alpha ,\beta $-conjugated carbonyl compounds have been a practical tool towards the synthesis of different useful heterocyclic compounds. Despite the numerous reactions with carbon-carbon double bond conjugated carbonyls, reactions of acetylenic carbonyls are limited. In this study, efficient dioxole synthesis was carried out via acetylenic aldehydes and butadiene formation was preferred over cyclopropene formation via acetylenic esters as different functional groups on these substrates change the product distribution. Both reaction conditions (such as solvent and temperature) and electrophilic structure of metal carbenoids alter the product distribution; acceptor (A), donor-acceptor (DA), and acceptor-acceptor (AA) functionalized diazo compounds yield …
Investigation Of The Hydrogen Bond Donating Ability Of 1,8-Naphthalenediol By Nmr Spectroscopy And Its Use As A Hydrogen Bonding Catalyst, Yunus Emre Türkmen
Investigation Of The Hydrogen Bond Donating Ability Of 1,8-Naphthalenediol By Nmr Spectroscopy And Its Use As A Hydrogen Bonding Catalyst, Yunus Emre Türkmen
Turkish Journal of Chemistry
The hydrogen bond donating ability of 1,8-naphthalenediol was investigated via a series of $^{1}$H, $^{13}$C, and $^{31}$P NMR experiments. Complexation studies using triphenylphosphine oxide and cyclohexanone as hydrogen bond acceptors revealed that 1,8-naphthalenediol is a more effective hydrogen bond donor compared to 1-naphthol and 8-methoxy-1-naphthol. Afterwards, its effectiveness as a hydrogen bonding catalyst was demonstrated in the Friedel-Crafts-type addition reaction of indole to trans-$\beta $-nitrostyrene.
A Novel Core-Shell-Based Chromatographic Method Supported By Ratio Derivative Spectrophotometry For The Simultaneous Determination Of Perindopril, Indapamide, And Amlodipine Ternary Mixtures, Leyla Karadurmuş, Mehmet Gümüştaş, Sevi̇nç Kurbanoğlu, Bengi̇ Uslu, Si̇bel Ayşil Özkan
A Novel Core-Shell-Based Chromatographic Method Supported By Ratio Derivative Spectrophotometry For The Simultaneous Determination Of Perindopril, Indapamide, And Amlodipine Ternary Mixtures, Leyla Karadurmuş, Mehmet Gümüştaş, Sevi̇nç Kurbanoğlu, Bengi̇ Uslu, Si̇bel Ayşil Özkan
Turkish Journal of Chemistry
}In this work, ratio spectra of the first derivative spectrophotometric and liquid chromatographic methods have been described for the first time for the simultaneous determination of perindopril (PER), indapamide (IND), and amlodipine (AML) in dosage forms. For chromatographic separations several mobile phase compositions were tested for efficient separation with the use of a new column technology related to superficially porous particles. Optimum chromatographic separation was achieved using a Kinetex C18 column (150 $\times $ 4.6 mm I.D. 5 $\mu $m) at a flow rate of 1.5 mL min$^{-1}$. The separation was carried out at 30 $^{\circ}$C and the diode array …
Recent Synthetic Methodologies For Pyrimidine And Its Derivatives, Farhat Ibraheem, Furqan Ahmad Saddique, Sana Aslam, Asim Mansha, Tahir Farooq, Matloob Ahmad
Recent Synthetic Methodologies For Pyrimidine And Its Derivatives, Farhat Ibraheem, Furqan Ahmad Saddique, Sana Aslam, Asim Mansha, Tahir Farooq, Matloob Ahmad
Turkish Journal of Chemistry
Pyrimidine derivatives are well known due to their remarkable pharmacological potential in various fields of science, and they are also present in some natural substances like DNA and RNA. These scaffolds manifest diversified biological activities such as antimicrobial, antiinflammatory, anti-HIV, antitubercular, antitumor, antineoplastic, and antimalarial. A pyrimidine ring is constructed when chalcones, amidines, guanidine, nitriles, isocyanates, urea, thiourea, and aminopyrazoles undergo condensation, coupling, or cyclization reactions. In this context, the present review illustrates a variety of novel and efficient synthetic approaches towards the synthesis of pyrimidine and its derivatives that were reported recently.
Synthesis Of Acetamide Derivatives Of 1,2,4-Triazole Bearing Azinane And Their Binding Interactions With Bovine Serum Albumin Using Spectroscopic Techniques, Javed Iqbal, Aziz Ur Rehman, Muhammad Athar Abbasi, Sabahat Zahra Siddiqui, Hira Khalid, Sabina Jhaumeer Laulloo, Nausheen Joondan, Aniisah Banu Taupass, Shahid Rasool, Syed Adnan Ali Shah
Synthesis Of Acetamide Derivatives Of 1,2,4-Triazole Bearing Azinane And Their Binding Interactions With Bovine Serum Albumin Using Spectroscopic Techniques, Javed Iqbal, Aziz Ur Rehman, Muhammad Athar Abbasi, Sabahat Zahra Siddiqui, Hira Khalid, Sabina Jhaumeer Laulloo, Nausheen Joondan, Aniisah Banu Taupass, Shahid Rasool, Syed Adnan Ali Shah
Turkish Journal of Chemistry
A new series of acetamide derivatives containing 1,2,4-triazole and azinane moieties has been synthesized and characterized using $^{1}$H NMR, $^{13}$C NMR, IR, and EI-MS spectroscopic analysis. The intermediate triazole was synthesized through a sequential synthesis of carboxylate and carbohydrazide. The bovine serum albumin (BSA) binding of the newly synthesized 1,2,4-triazole derivatives was evaluated along with thermodynamics, site-selective binding, and synchronous study. The results obtained by BSA binding as well as thermodynamic studies justify that all the compounds show spontaneous interaction with BSA and could be effectively distributed and eliminated from the body. Therefore, the triazole-based analogs might be a useful …
Fabrication And Electrochemical Performance Of La$_{0.595}$V$_{0.005}$Sr$_{0.4}$Mno$_{3-\Delta }$ (Lv05sm) Cathode Material For Solid Oxide Fuel Cells, Ayşenur Eslem Kisa, Oktay Demi̇rcan
Fabrication And Electrochemical Performance Of La$_{0.595}$V$_{0.005}$Sr$_{0.4}$Mno$_{3-\Delta }$ (Lv05sm) Cathode Material For Solid Oxide Fuel Cells, Ayşenur Eslem Kisa, Oktay Demi̇rcan
Turkish Journal of Chemistry
This study reports the effect of vanadium on the crystal structure and electrical and electrochemical properties of La$_{0.6-x}$V$_{x}$Sr$_{0.4}$MnO$_{3-\delta \, }(x =$ 0.005--0.1) perovskite-based cathode materials in solid oxide fuel cells. Crystal structure, morphology, and porosity of prepared cathode materials are characterized by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. Using XPS analysis it was established that the La$^{3+}$ cation is exchanged by the V$^{4+/5+}$ cation in the perovskite structure. This ion replacement improves the ionic conductivity and catalytic activity for oxygen reduction reaction in the perovskite structure, presumably due to the smaller size of the V$^{4+/5+}$ cation …
Synthesis, Spectroscopic Characterization, And Computational Studies Of 2-Cyano-6-Hydroxybenzothiazole: A Key Synthetic Intermediate Of Firefly Luciferin, Ghasem Shahmoradi, Saeid Amani
Synthesis, Spectroscopic Characterization, And Computational Studies Of 2-Cyano-6-Hydroxybenzothiazole: A Key Synthetic Intermediate Of Firefly Luciferin, Ghasem Shahmoradi, Saeid Amani
Turkish Journal of Chemistry
Firefly luciferin is widely applied as a biotechnological tool for visualizing various biological processes in vitro and in vivo. Chemically, 2-cyano-6-hydroxybenzothiazole, as a key synthetic intermediate of firefly luciferin, is obtained from 2-cyano-6-methoxybenzothiazole by changing the methoxy with a hydroxy group. However, this approach is costly and not suited for large-scale synthesis. Here we report cost-effective and efficient syntheses of 2-cyano-6-hydroxybenzothiazole through the catalytic Sandmeyer-type cyanation reaction. Our approach employs diazonium tetrafluoroborate salt of 2-amino-6-hydroxybenzothiazole as a cyanation substrate. The cyanation reaction proceeds efficiently under mild conditions by using Cu(I)/Cu(II)/N,N,N\textquotesingle,N\textquotesingle-tetramethylethylenediamine as a catalyst. In addition, computational studies of the 2-cyano-6-hydroxybenzothiazole …
Synthesis Of $E$-Stilbene Azomethines As Potent Antimicrobial And Antioxidant Agents, Ahsan Iqbal, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Muhammad Usman, Shakeel Ahmad Khan, Abdul H. Fauq, Ayesha Bari, Muhammad Aamir Sajid
Synthesis Of $E$-Stilbene Azomethines As Potent Antimicrobial And Antioxidant Agents, Ahsan Iqbal, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Muhammad Usman, Shakeel Ahmad Khan, Abdul H. Fauq, Ayesha Bari, Muhammad Aamir Sajid
Turkish Journal of Chemistry
A series of new extensively conjugated $E$-stilbene azomethines (5a-5h) were synthesized and screened for their antioxidant and antimicrobial activity. The compounds were tested against bacterial (Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Bacillus subtilis) and fungal strains (Aspergillus niger, A. flavus, and Trichoderma harzianum) using the agar well diffusion method. Among the tested compounds, $N$'-(4-nitrobenzylidene)-2-(($E)$-styryl)benzohydrazide (5g) was found to possess potent antimicrobial activity higher than some drugs with significant activity reported in the literature, e.g., cefradine and terbinafine hydrochloride. Additionally, compounds 5a-5h were also evaluated for antioxidant potential using DPPH free radical scavenging and ferric thiocyanate (FTC) assays. Among these, …
Determination Of Morin On An Electrochemically Activated Carbon-Paste Electrode, Alexander Chebotarev, Konstantin Pliuta, Denys Snigur
Determination Of Morin On An Electrochemically Activated Carbon-Paste Electrode, Alexander Chebotarev, Konstantin Pliuta, Denys Snigur
Turkish Journal of Chemistry
In this paper, the possibility of using an electrochemically activated carbon-paste electrode (ECA-CPE) for the determination of morin has been studied. It is established that the oxidation current increases 1.85 times in comparison with untreated CPE. The adsorption nature of the anodic current and the number of electrons taking part in the oxidation of morin on ECA-CPE was established. The optimal conditions for the determination of morin (pH $=$ 4, E$_{ads\, }=$ 200~mV, t$_{ads\, }=$ 180 s) were established. Using square-wave voltammetry (A $=$ 35 mV, $\nu =$ 25 Hz, $\upsilon =$ 100 mV/s) it is possible to determine morin …
Effect Of Ph On The Complexation Of Irbesartan With $\Beta $-, Hydroxypropyl-$\Beta $-, And $\Gamma $-Cyclodextrin: Solubility Enhancement And Physicochemical Characterization, Fakhri Yousef
Turkish Journal of Chemistry
The affinity of irbesartan (IRB) to form inclusion complexes with $\beta $-cyclodextrin ($\beta $-CD), hydroxypropyl-$\beta $-cyclodextrin (HP-$\beta $-CD), and $\gamma $-cyclodextrin ($\gamma $-CD) was investigated in aqueous buffered solutions at pH 1.7, 4.1, and 7.0. Analysis of the UV absorption-pH profiles revealed that IRB has two p$K_{a}$ values: p$K_{a1\, }=$ 3.60 (imidazolinone ring moiety) and p$K_{a2\, }=$ 4.70 (tetrazole moiety). In the presence of 5.0 mmol L$^{-1} \beta $-CD, the tetrazole moiety became more acidic, indicating its inclusion within the $\beta $-CD cavity. Phase-solubility diagrams (PSDs) were obtained for IRB in aqueous buffered solutions of $\beta $-CD, HP-$\beta $-CD, and …
Synthesis And Investigation Of Langbeinite-Related Strontium- And Iron-Containing Phosphates, Nataliia Strutynska, Nikolai Slobodyanik, Anastasiia Shatalova
Synthesis And Investigation Of Langbeinite-Related Strontium- And Iron-Containing Phosphates, Nataliia Strutynska, Nikolai Slobodyanik, Anastasiia Shatalova
Turkish Journal of Chemistry
The partial substitution of potassium atoms by strontium atoms in initial matrix K$_{3}$Fe$_{2}$(PO$_{4})_{3}$ with formation of complex phosphates K$_{3-2x}$Sr$_{x}$Fe$_{2}$(PO$_{4})_{3}$ ($x =$ 0.75, 1.0, and 1.25) was determined using a solid-state reaction method. According to powder X-ray diffraction (XRD) data, the prepared phosphates with $x =$ 1.0 and 1.25 crystallize in a cubic system (space group ${P2}_{1}$3) and belong to langbeinite family compounds, while for the sample with $x =$ 0.75 a mixture of langbeinite-type phase and a minor amount of K$_{3}$Fe$_{2}$(PO$_{4})_{3}$ was obtained. The decreasing trend of lattice parameter $a$ with increase of Sr amount in the phosphate confirmed the …
4d-Qsar Analysis And Pharmacophore Modeling For Alkynylphenoxyacetic Acids As Crth2 (Dp2) Receptor Antagonists, Semi̇ha Köprü, Emi̇n Saripinar
4d-Qsar Analysis And Pharmacophore Modeling For Alkynylphenoxyacetic Acids As Crth2 (Dp2) Receptor Antagonists, Semi̇ha Köprü, Emi̇n Saripinar
Turkish Journal of Chemistry
In this study, we performed the pharmacophore modeling and 4D-QSAR research of alkynylphenoxyacetic acid analogues as CRTh2 receptor opponent agents by utilizing the electron conformational genetic algorithm method. Quantum chemical calculations and conformational analyses of the compounds were carried out at HF/6-31G* level. Then electron conformational matrices of congruity were prepared for each conformer of each compound, which are represented by electronic and structural properties. As a result of the comparison of the matrices that are called electron conformational submatrices of activity, the pharmacophoric group of the compounds responsible for the activity was found at the determined tolerance intervals. The …
An Efficient Water-Mediated Synthetic Route For The Alkylation Of Heteroarenes, Pinar Seyi̇tdanlioğlu, Essam Hamied Ahmed Hanashalhalshahaby, Canan Ünaleroğlu
An Efficient Water-Mediated Synthetic Route For The Alkylation Of Heteroarenes, Pinar Seyi̇tdanlioğlu, Essam Hamied Ahmed Hanashalhalshahaby, Canan Ünaleroğlu
Turkish Journal of Chemistry
An efficient synthetic route has been described for the alkylation of 1$H$-indole, 1$H$-benzimidazole, and 1$H$-benzotriazole. This approach features the alkylation of heteroaromatics through in situ generated enones from ketonic Mannich bases under metal-free conditions. A series of alkylated heteroaromatics have been synthesized via the K10 catalyzed alkylation reactions of these heteroaromatics with a variety of ketonic Mannich bases. Environmentally benign K10 catalyst, water-mediated mild reaction conditions, and the efficient synthesis of alkylated products are the advantages of this alkylation method.
Metal Nanoparticles/Carbon Nanotube Modified Electrodes For Voltammetric Determination Of Boron, Lokman Li̇v, Zekerya Dursun, Nuri̇ Naki̇boğlu
Metal Nanoparticles/Carbon Nanotube Modified Electrodes For Voltammetric Determination Of Boron, Lokman Li̇v, Zekerya Dursun, Nuri̇ Naki̇boğlu
Turkish Journal of Chemistry
This study describes a sensitive and accurate voltammetric method for determination of boron using metal nanoparticles/carbon nanotube modified electrodes. The oxidation peak of Alizarin Red S (ARS) at -0.59 V in the boron-ARS complex formed in ammonium/ammonia buffer solution (pH 8.5) was evaluated as a response. The electrode modification conditions and experimental parameters affecting the peak height were optimized. The characteristics of modified electrodes were investigated using cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscope, energy dispersive X-ray spectroscopy, high resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The limits of detection (3s$_{y/x})$ and the analytical ranges for gold nanoparticles/carbon …
Design And Synthesis Of New Naphtho[2,1-$B$]Pyrano [2,3-$D$]Pyrimidinones Under Classical And Microwave Conditions, Maher Cherif, Mariem Debbabi, Sarra Chortani, Anis Romdhane, Hichem Ben Jannet
Design And Synthesis Of New Naphtho[2,1-$B$]Pyrano [2,3-$D$]Pyrimidinones Under Classical And Microwave Conditions, Maher Cherif, Mariem Debbabi, Sarra Chortani, Anis Romdhane, Hichem Ben Jannet
Turkish Journal of Chemistry
A fast and efficient method for the synthesis of naphthopyranopyrimidinones derivatives in excellent yields was developed through cyclocondensation reaction between previously prepared pyrimidinic hydrazides and some electrophilic species such as 2,4-pentanedione, 2,5-hexanedione, cyclic anhydrides, and phenylthioisocyanate under microwave irradiation. Compared to the conventional methods applied, it was found that better yields and shorter reaction times were achieved using microwave-assisted synthesis. Structures of all synthesized compounds were established on the basis of spectroscopic methods including $^{1}$H NMR, $^{13}$C NMR, and HRMS-ES.
Synergetic Effect Of Mn, Ce, Ba, And B Modification And Moderate Desilication Of Nanostructured Hzsm-5 Catalyst On Conversion Of Methanol To Propylene, Fatemeh Yahyazadeh Saravi, Majid Taghizadeh
Synergetic Effect Of Mn, Ce, Ba, And B Modification And Moderate Desilication Of Nanostructured Hzsm-5 Catalyst On Conversion Of Methanol To Propylene, Fatemeh Yahyazadeh Saravi, Majid Taghizadeh
Turkish Journal of Chemistry
Modified mesoporous HZSM-5 catalysts were prepared by controlled desilication using a mixture of NaOH and TPAOH (tetrapropylammonium hydroxide) and impregnation of metals (Mn, Ce, and Ba) and metalloid B. The catalytic performances of all prepared catalysts for methanol to propylene (MTP) reaction were evaluated in a fixed bed reactor under atmospheric pressure at 480 \textdegree C. The parent and modified catalysts were characterized by XRD, ICP-OES, FE-SEM, NH$_{3}$-TPD, FT-IR, BET, and TGA techniques. The catalyst loaded with 2 wt.% manganese on desilicated HZSM-5 demonstrated the best catalytic performance in terms of the highest selectivity of C$_{2}^{=}$ to C$_{4}^{=}$ olefins (about …
Neutral Atoms And Ion Energies, Accurate Ionization Potential, And Electron Affinities By Polynomial Generator Coordinate Hartree--Fock Method, Fernando Ratuchne, Ricardo Celeste
Neutral Atoms And Ion Energies, Accurate Ionization Potential, And Electron Affinities By Polynomial Generator Coordinate Hartree--Fock Method, Fernando Ratuchne, Ricardo Celeste
Turkish Journal of Chemistry
We have developed accurate Gaussian basis functions obtained with the polynomial generator coordinate Hartree-Fock (p-GCHF) method for H, Zn, and Ga-Kr atoms. These basis sets have been applied in the calculation of nonrelativistic energies for neutral atoms, monovalent cations, monovalent anions, ionization potential (IP), and electron affinity (EA), with the objective of proving the quality of the basis set generated by the p-GCHF method. The total energies calculated for neutral atoms and monovalent cations and respective IP were minimally affected by the addition of polarization functions and their precision was comparable to the values reported in the literature. The relative …
Novel Optical Sensor-Based Method For Determining Total Tocopherol Content In Serum, Mustafa Bener, Mustafa Reşat Apak
Novel Optical Sensor-Based Method For Determining Total Tocopherol Content In Serum, Mustafa Bener, Mustafa Reşat Apak
Turkish Journal of Chemistry
Lipid-soluble endogenous antioxidants, such as tocopherols, protect biological structures from oxidative damage through their chain-breaking ability and thus the development of a simple method for tocopherol determination is important. In this study, a novel optical sensor-based method was proposed for determining total tocopherol content (TTC) of serum, with selectivity for $\alpha $-tocopherol over $\beta $-carotene. The proposed method is based on the use of a copper(II)-neocuproine complex (Cu(II)-Nc) reagent immobilized onto a Nafion membrane, and the absorbance changes associated with the formation of Cu(I)-Nc chelate on the membrane strip as a result of reaction with serum tocopherols were measured at …
Quantification Of Flavonoids Isolated From \Textit{Mentha Spicata} In Selected Clones Of Turkish Mint Landraces, Ramazan Erenler, İsa Telci̇, Mahfuz Elmastaş, Hüseyi̇n Akşi̇t, Fati̇h Gül, Ali̇ Riza Tüfekçi̇, İbrahi̇m Demi̇rtaş, Ömer Kayir
Quantification Of Flavonoids Isolated From \Textit{Mentha Spicata} In Selected Clones Of Turkish Mint Landraces, Ramazan Erenler, İsa Telci̇, Mahfuz Elmastaş, Hüseyi̇n Akşi̇t, Fati̇h Gül, Ali̇ Riza Tüfekçi̇, İbrahi̇m Demi̇rtaş, Ömer Kayir
Turkish Journal of Chemistry
Mint has been used extensively in traditional medicines, spices, and herbal teas throughout the world. Isolation of flavonoids from Mentha spicata and quantification of these compounds in selected clones of Turkish mints landraces were achieved. M. spicata was dried in shade and then boiled in water. After filtration, the aqueous extract was partitioned with ethyl acetate. The solvent was removed under reduced pressure to yield the extract, subjected to silica gel column chromatography to isolate 5-demethyl sinensetin (1), hesperidin (2), didymin (3), and linarin (4), the structures of which were elucidated by 1D NMR, 2D NMR, and LC-TOF/MS. The isolated …
The Catalytic Effects Of In Situ Prepared N-Heterocyclic Carbenes From Benzimidazole Salts In Suzuki--Miyaura Cross-Coupling Reaction And Uses In Catalytic Preparation Of 1,3,5-Triphenyl-1,3,5-Triazinane-2,4,6-Trione From Phenyl Isocyanate, Ülkü Yilmaz, Hasan Küçükbay
The Catalytic Effects Of In Situ Prepared N-Heterocyclic Carbenes From Benzimidazole Salts In Suzuki--Miyaura Cross-Coupling Reaction And Uses In Catalytic Preparation Of 1,3,5-Triphenyl-1,3,5-Triazinane-2,4,6-Trione From Phenyl Isocyanate, Ülkü Yilmaz, Hasan Küçükbay
Turkish Journal of Chemistry
Many benzimidazole salts bearing a 3-phenylpropyl substituent (1a-1h) were synthesized and their structures were identified by $^{1}$H NMR, $^{13}$C NMR, and IR spectroscopic methods and elemental analysis. These N-heterocyclic carbene (NHC) precursors were used as a part of a catalytic system including Pd(OAc)$_{2}$ and the base in the Suzuki--Miyaura cross-coupling reaction under microwave irradiation. They were also used as catalysts in the cyclotrimerization of phenyl isocyanate to yield 1,3,5-triphenyl-1,3,5-triazinane-2,4,6-trione. It has been observed that benzimidazole salts made a positive contribution to both catalytic reactions as a NHC precursor.
Optimization Of Sugarcane Bagasse Activation To Achieve Adsorbent With High Affinity Towards Phenol, Seyed-Abolfazl Mohtashami, Neda Asasian Kolur, Tahereh Kaghazchi, Reza Asadi-Kesheh, Mansooreh Soleimani
Optimization Of Sugarcane Bagasse Activation To Achieve Adsorbent With High Affinity Towards Phenol, Seyed-Abolfazl Mohtashami, Neda Asasian Kolur, Tahereh Kaghazchi, Reza Asadi-Kesheh, Mansooreh Soleimani
Turkish Journal of Chemistry
Sugarcane bagasse as an agricultural/industrial biomass was converted into a low-cost activated carbon via an acid activation procedure under optimized conditions. Phosphoric acid was applied as a cost-effective and environmentally friendly chemical activator. The optimized activated carbon produced under temperature of 550 \textdegree C and impregnation ratio of 1.5 showed a micromesoporous structure with specific surface area and pore volume of 972.5 m$^{2}$/g and 0.43 cm$^{3}$/g, respectively. The adsorption capacity of the produced AC towards phenol was measured and, after only 30 min, the removal percentage reached over 95%. The greatest affinity towards phenol was obtained at pH of 4 …
Voltammetric Determination Of Glycopyrrolate In A Pharmaceutical Formulation, Muneer Fadr, Abdulaziz Nabil Amro, Sami Ben Aoun, Samer Ratrout, Fadi Asfour
Voltammetric Determination Of Glycopyrrolate In A Pharmaceutical Formulation, Muneer Fadr, Abdulaziz Nabil Amro, Sami Ben Aoun, Samer Ratrout, Fadi Asfour
Turkish Journal of Chemistry
The electrochemical activity of glycopyrrolate was studied. Different voltammetric techniques were applied in this study, including cyclic voltammetry (CV), differential pulse voltammetry (DPV), and linear sweep voltammetry (LSV). Glassy carbon and platinum working electrodes were utilized. CV indicated that glycopyrrolate has a reversible redox reaction on the working electrode surface, with an anodic peak current at approximately 1.05 V and a cathodic peak at 0.80 V. Several parameters that affect the sensitivity of these methods were optimized for the quantitation of glycopyrrolate. LSV showed a better correlation coefficient than DPV did, with a value of ca. 0.9990 in the range …
Experimental And Theoretical Study Of Nh$_{3}$ Adsorption And Desorption Over A Cu-Chabazite Nh$_{3}$-Scr Catalyst, Selmi̇ Eri̇m Bozbağ, Mutlu Şi̇mşek, Onur Demi̇r, Deni̇z Şanli Yildiz, Hüseyi̇n Barkin Özener, Gökhan Hi̇sar, Can Erkey
Experimental And Theoretical Study Of Nh$_{3}$ Adsorption And Desorption Over A Cu-Chabazite Nh$_{3}$-Scr Catalyst, Selmi̇ Eri̇m Bozbağ, Mutlu Şi̇mşek, Onur Demi̇r, Deni̇z Şanli Yildiz, Hüseyi̇n Barkin Özener, Gökhan Hi̇sar, Can Erkey
Turkish Journal of Chemistry
NH$_{3}$ adsorption and desorption behavior of a commercial Cu-chabazite (CHA) NH$_{3}$ selective catalytic reduction (NH$_{3}$-SCR) catalyst was studied in the presence and absence of H$_{2}$O. NH$_{3}$ uptake values at various adsorption temperatures were obtained during various steps of the adsorption and temperature-programmed desorption (TPD) experiments. Total NH$_{3}$ uptake decreased from 4.6 to 1.6 g NH$_{3}$/L catalyst when the adsorption temperature was increased from 50 to 300 $^{\circ}$C. Three major adsorption sites for NH$_{3}$ adsorption could be identified and quantified using TPD experiments, namely loosely, moderately, and strongly bound NH$_{3}$ with peak centers at around 147, 266, and 447 $^{\circ}$C. The …
Hybrid Organic Molecules As Antiinammatory Agents; A Review Of Structuralfeatures And Biological Activity, Noor Ul Amin Mohsin, Matloob Ahmad
Hybrid Organic Molecules As Antiinammatory Agents; A Review Of Structuralfeatures And Biological Activity, Noor Ul Amin Mohsin, Matloob Ahmad
Turkish Journal of Chemistry
Nonsteroidal antiin ammatory drugs (NSAIDs) are widely used for the treatment of pain and in ammation. Some undesirable effects are linked with NSAIDs such as the gastrointestinal tract (GIT) toxicity and cardiovascular disturbances. At present the preparation of a hybrid molecular technique is being used to produce new analgesic and antiin ammatory molecules. Attachment of NSAIDs with nitric oxide and hydrogen sulfide releasing molecules produced some gastroprotective agents with improved analgesic and antiinflammatory activities. Combination of NSAIDs with different biologically active 5-membered, 6-membered, and condensed heterocyclic rings has also led to the formation of some potent molecules. Some of these …