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Articles 1141 - 1170 of 1672
Full-Text Articles in Chemistry
Tetrahydronaphthalene As A Precursor Of New Series Of Chalcones, Flavanones, And Flavones, Ahmed Meddeb, Ghalia Bouhalleb, Julien Legros, Farhat Rezgui
Tetrahydronaphthalene As A Precursor Of New Series Of Chalcones, Flavanones, And Flavones, Ahmed Meddeb, Ghalia Bouhalleb, Julien Legros, Farhat Rezgui
Turkish Journal of Chemistry
An efficient synthetic route for a novel series of chalcones 2a-2d as well as for the corresponding flavanones 3a-3d and flavones 4a-4d, using functionalized tetrahydronaphthalene (THN), is described herein. The Claisen-Schmidt condensation of such THN and aromatic aldehydes, in the presence of an aqueous solution of KOH (40%), selectively gives the expected chalcones 2a-2d, which may further undergo an intramolecular oxa-Michael addition using piperidine, affording the corresponding flavanones 3a-3d in high yields. Alternatively, treatment of such chalcones 2a-2d with I$_{2}$/DMSO provides rapidly, in a one-pot oxidative cyclization, a series of flavones 4a-4d in excellent yields ranging from 85% to 90%.
Effect Of Ph And $\Beta$-Cyclodextrin On The Photophysical Properties Of Lamotrigine, Raed Ghanem, Fakhri Yousef, Omar Abu Awwad
Effect Of Ph And $\Beta$-Cyclodextrin On The Photophysical Properties Of Lamotrigine, Raed Ghanem, Fakhri Yousef, Omar Abu Awwad
Turkish Journal of Chemistry
Photophysical properties of lamotrigine (LMT) were investigated at different pH values. Lamotrigine exhibited a broad absorption band at 308 nm that was shifted to 268 nm at pH 2.0 due to protonation (HLMT$+)$. Emission spectra of LMT at different pH values showed a single band at 483 nm except for at pH 2.0, where a second band at 502 nm was observed due to the deprotonation from the singlet excited state. LMT pH profile was used to calculate p$K$a of LMT in excited and ground states (p$K$a* $=$ 4.50 and p$K$a $=$ 5.90). Absorption spectra of LMT at different pH …
Transfer Of The Protonable Surfactant Dipalmitoyl-Phosphatidylcholine Across A Large Liquid/Liquid Interface: A Voltammetric Study, İbrahi̇m Uyanik
Transfer Of The Protonable Surfactant Dipalmitoyl-Phosphatidylcholine Across A Large Liquid/Liquid Interface: A Voltammetric Study, İbrahi̇m Uyanik
Turkish Journal of Chemistry
Adsorption behavior of the zwitterionic phospholipid dipalmitoyl-phosphatidylcholine (DPPC) at the polarizable liquid/liquid interface formed between water and 1,2-dichloroethane electrolyte solutions is studied taking into account both the pH of the aqueous phase and the concentration of the phospholipid in the organic phase by cyclic voltammetry. Experimental results showed that the adsorption of the phospholipid strongly depends on the pH of the aqueous phase, which determines the surface ionization of the polar head of the phospholipid molecule and hence the stability of the adsorbed layer of phospholipids.
Voltammetric Determination Of Vanillin In Commercial Food Products Using Overoxidized Poly(Pyrrole) Film-Modified Glassy Carbon Electrodes, Şükri̇ye Ulubay Karabi̇beroğlu, Çağri Ceylan Koçak
Voltammetric Determination Of Vanillin In Commercial Food Products Using Overoxidized Poly(Pyrrole) Film-Modified Glassy Carbon Electrodes, Şükri̇ye Ulubay Karabi̇beroğlu, Çağri Ceylan Koçak
Turkish Journal of Chemistry
In this work, a very simple, rapid, cheap, sensitive, and selective polymer film-modified electrode for vanillin determination in commercial food products was developed via electrochemical polymerization and overoxidation of pyrrole. The formation of both poly(pyrrole) and overoxidized poly(pyrrole) films on a glassy carbon electrode surface was characterized by electrochemical impedance spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Under optimized conditions, the calibration graph comprises two linear segments of 0.032-1.500 $\mu $mol L$^{-1}$ and 3.00--150.00 $\mu $mol L$^{-1}$ with a detection limit of 0.012 $\mu $mol L$^{-1}$. The selectivity of the modified electrode was examined in the presence of metals, …
Synthesis And Biological Properties Of Novel1-Methyl-2-(2-(Prop-2-Yn-1-Yloxy)Benzylidene) Hydrazine Analogues, Ari̇f Kivrak, Can Yilmaz, Meti̇n Konuş, Hali̇l Koca, Selahatti̇n Aydemi̇r, Jeger Ali Oagaz
Synthesis And Biological Properties Of Novel1-Methyl-2-(2-(Prop-2-Yn-1-Yloxy)Benzylidene) Hydrazine Analogues, Ari̇f Kivrak, Can Yilmaz, Meti̇n Konuş, Hali̇l Koca, Selahatti̇n Aydemi̇r, Jeger Ali Oagaz
Turkish Journal of Chemistry
1-Methyl-2-(2-(prop-2-yn-1-yloxy)benzylidene)hydrazine analogues were readily prepared in good yields by the reaction of 2-(prop-2-yn-1-yloxy)benzaldehydes and methyl hydrazine. The reaction tolerates a variety of substituents on the 2-hydroxybenzaldehyde to form nitro-, halo-, methoxy-, and naphthyl-substituted 1-methyl-2-(2-(prop-2-yn-1-yloxy)benzylidene)hydrazines. The in vitro antioxidant capacity measurements revealed that among all the analyzed hydrazine analogues that surpassed the Trolox standard, 1-(2-(but-3-ynyl)-5-nitrobenzylidene)-2-methylhydrazine had the maximum value, which was approximately 1.7 times that of Trolox.
A New Member Of Mo36- Polyoxoanion's Family: Synthesis, Crystal Structure, And Physico-Chemical Properties Of K$_{10}$[Mo$_{36}$O$_{110}$ (Oh)$_{6}$ (H$_{2}$O)$_{12}$].38 H$_{2}$O, Jawaher Baizig, Anissa Haj Abdallah, Amor Haddad
A New Member Of Mo36- Polyoxoanion's Family: Synthesis, Crystal Structure, And Physico-Chemical Properties Of K$_{10}$[Mo$_{36}$O$_{110}$ (Oh)$_{6}$ (H$_{2}$O)$_{12}$].38 H$_{2}$O, Jawaher Baizig, Anissa Haj Abdallah, Amor Haddad
Turkish Journal of Chemistry
The new giant Mo$_{36}$ polyoxomolybdate formulated as K$_{10}$[Mo$_{36}$O$_{110}$(OH)$_{6}$ (H$_{2}$O)$_{12}$].38 H$_{2}$O (1) was isolated by conventional solution method by the reaction of K$_{2}$MoO$_{4}$ and KNO$_{3}$ in aqueous solution (pH = 1.8), at room temperature, and structurally characterized by single-crystal X-ray diffraction methods. The title compound crystallized in the monoclinic system, space group P2$_{1}$/n with unit a = 16.5180 (0) Å, b = 18.4485 (0) Å, c = 24.2424 (0) Å, $\alpha $ = 90.00$^{\circ}$, $\beta $ = 99.51$^{\circ}$, $\gamma $ = 90.00$^{\circ}$, V = 7285.79 (0) Å$^{3}$, and Z = 2. The refinement of the structure led to a residual factor …
Development Of A Molecularly Imprinted Polymer-Based Electrochemical Sensor For Tyrosinase, Aysu Yarman
Development Of A Molecularly Imprinted Polymer-Based Electrochemical Sensor For Tyrosinase, Aysu Yarman
Turkish Journal of Chemistry
For the first time a molecularly imprinted polymer (MIP)-based sensor for tyrosinase is described. This sensor is based on the electropolymerization of scopoletin or o-phenylenediamine in the presence of tyrosinase from mushrooms, which has a high homology to the human enzyme. The template was removed either by treatment with proteinase K or by alkaline treatment. The measuring signal was generated either by measuring the formation of a product by the target enzyme or by evaluation of the permeability of the redox marker ferricyanide. The o-phenylenediamine-based MIP sensor has a linear measuring range up to 50 nM of tyrosinase with a …
Nickel(Ii)-Pph$_{3}$ Complexes With Ons And Onn Chelating Thiosemicarbazones: Synthesis And Inhibition Potential On Influenza A Viruses, Şükri̇ye Güveli̇, Kadi̇r Turan, Bahri̇ Ülküseven
Nickel(Ii)-Pph$_{3}$ Complexes With Ons And Onn Chelating Thiosemicarbazones: Synthesis And Inhibition Potential On Influenza A Viruses, Şükri̇ye Güveli̇, Kadi̇r Turan, Bahri̇ Ülküseven
Turkish Journal of Chemistry
Tetra-coordinated nickel(II) complexes of two ONS (1, \2) and seven ONN (3a-3g) chelating 2-hydroxy-3-methoxy-benzaldehyde thiosemicarbazones were synthesized. The dibasic ligands and complexes bearing PPh$_{3}$ as a coligand were characterized by means of analytical and spectroscopic data. Cytotoxic activities of the ligands and nickel(II) complexes were determined using the MTT assay in vitro against MDCK cells, and then all the compounds were tested on influenza virus replication by plaque assays. The compounds showed GI$_{50}$ values varying from concentrations of 15.9 up to 161.8 $\mu$ g/mL for MDCK cells. The plaque assays indicated that one ONS (1) and two ONN (3c and …
Peg-Peptide Conjugate Containing Cathepsin B Degradation Unit As A Doxorubicin Carrier System, Nesli̇gül Şentürk, Ayben Top
Peg-Peptide Conjugate Containing Cathepsin B Degradation Unit As A Doxorubicin Carrier System, Nesli̇gül Şentürk, Ayben Top
Turkish Journal of Chemistry
A drug delivery system (DDS) containing a cathepsin B degradable sequence and pH-responsive histidines was prepared by methoxypolyethylene glycol and peptide conjugation. Doxorubicin was attached to the carrier system using amide linkage to give the final form of the DDS, denoted as mPEG-AT3-DOX. mPEG-AT3-DOX exhibited a bimodal size distribution at about 15 and 30 nm independent of pH, whereas the size of the control DDS containing no peptide sequence, mPEG-DOX, was measured as $\sim$ 15-20 nm. At the end of 72 h, % doxorubicin release from both of the DDSs was observed to be below 8.5 $\pm$ 3% in the …
Synthesis, Biological Evaluation, And In Silico Study Of Some Unique Multifunctional 1,2,4-Triazole Acetamides, Almas Sattar, Aziz Ur Rehman, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Hira Khalid, Muhammad Arif Lodhi, Farman Ali Khan
Synthesis, Biological Evaluation, And In Silico Study Of Some Unique Multifunctional 1,2,4-Triazole Acetamides, Almas Sattar, Aziz Ur Rehman, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Hira Khalid, Muhammad Arif Lodhi, Farman Ali Khan
Turkish Journal of Chemistry
The imperative demand for antibacterial agents and enzyme inhibitors prompted us to synthesize some new compounds, 6a-6k, bearing multifunctional moieties. The target acetamides were derived from 4-phenyl-5-(1-tosylpiperidin-4-yl)-4$H$-1,2,4-triazole-3-thiol (3). The structural analysis was carried out using modern spectroscopic techniques including IR, NMR, and EIMS spectral analysis. The antibacterial activity was screened against five bacterial strains including three gram-negative and two gram-positive ones. Enzyme inhibition was carried out against lipoxygenase enzyme and results were supported by in silico study. The synthesized compounds were proved to be potent antibacterial agents and enzyme inhibitors.
Oxime-Containing Acetylcholinesterase Reactivators And Their Complexes With Pd(Ii) And Pt(Ii) Ions: Recent Developments, Ivayla Pantcheva, Ahmed Nedzhib, Liudmil Antonov
Oxime-Containing Acetylcholinesterase Reactivators And Their Complexes With Pd(Ii) And Pt(Ii) Ions: Recent Developments, Ivayla Pantcheva, Ahmed Nedzhib, Liudmil Antonov
Turkish Journal of Chemistry
The ability of oxime-containing acetylcholinesterase reactivators BT-07 (K005), BT-08 (K033), BT-07-4M (K074), and obidoxime (H$_{2}$LX$_{2}$, X = Cl$^{-}$, Br$^{-})$ to bind palladium(II) or platinum(II) cations was evaluated in aqueous solutions (pH 7.4) at metal-to-ligand molar ratio varying from 1:10 to 10:1. Spectral changes were monitored within a week after mixing the reagents in the range from 220 nm to 500 nm. Results showed that depending on chemical structure and reaction time, oximes form two complex species of composition, [MHL]$^{3+}$ or [M$_{2}$L]$^{4+}$ (M = Pd(II), Pt(II)). It was also found that complexation of platinum(II) ions proceeds slower as compared to palladium(II). …
A Novel Hypobromous Acid Scavenging Activity Assay Using $P$-Cresol As A Spectrofluorometric Probe, Burcu Bekdeşer, Gülüzar Zeytünlü, Mustafa Özyürek, Mustafa Reşat Apak
A Novel Hypobromous Acid Scavenging Activity Assay Using $P$-Cresol As A Spectrofluorometric Probe, Burcu Bekdeşer, Gülüzar Zeytünlü, Mustafa Özyürek, Mustafa Reşat Apak
Turkish Journal of Chemistry
In this study, a novel spectrofluorometric assay based on $p$-cresol (4-methyl phenol) probe is developed for the measurement of HOBr scavenging activity. It is the first study involving the use of a $p$-cresol probe for the determination of the HOBr scavenging activity of biothiols. While the $p$-cresol probe ($\lambda_{ex}$ = 260 nm, $\lambda_{em}$ = 305 nm) has fluorescence characteristics, its brominated derivatives emerging at the end of the oxidation reaction with HOBr do not show fluorescence. The initial fluorescence intensity of the $p$-cresol probe is decreased in the presence of the brominating agent, HOBr, and this decrease is lower in …
Application Of The Taguchi Approach To Optimize Zno Synthesis Via Hydrothermally Assisted Sol-Gel Method, Zahra Khaghanpour, Sanaz Naghibi
Application Of The Taguchi Approach To Optimize Zno Synthesis Via Hydrothermally Assisted Sol-Gel Method, Zahra Khaghanpour, Sanaz Naghibi
Turkish Journal of Chemistry
ZnO powder was synthesized via a hydrothermally assisted sol-gel method. Synthesis variables including Zn-precursor type, pH value, time, and temperature of hydrothermal treatment were analyzed using the Taguchi approach. The experimental procedures were defined based on the L9 array for four variables in three levels. The influences of those variables on the response parameters, i.e. crystallite size, crystallinity, band gap energy ($E_{g})$, and degradation constants ($k)$, were evaluated. XRD results and $E_{g}$ values showed that ZnO wurtzite appeared to be the only crystalline phase in the samples. Taguchi analysis predicted that the optimized conditions to achieve the highest photoactivity are …
Application Of A Pencil Graphite Electrode For Voltammetric Simultaneous Determination Of Ascorbic Acid, Norepinephrine, And Uric Acid In Real Samples, Abdulkadi̇r Levent, Günay Önal
Application Of A Pencil Graphite Electrode For Voltammetric Simultaneous Determination Of Ascorbic Acid, Norepinephrine, And Uric Acid In Real Samples, Abdulkadi̇r Levent, Günay Önal
Turkish Journal of Chemistry
A pencil graphite electrode (PGE) was used for the simultaneous detection of ascorbic acid (AA), norepinephrine (NE), and uric acid (UA) by differential pulse voltammetry and cyclic voltammetry. The anodic peaks of AA, NE, and UA in their mixture can be well separated in 0.1 M Britton--Robinson buffer solution at pH 4.0. The effects of various experimental parameters such as pH, scan rate, and voltammetric parameters on the voltammetric response of these compounds were investigated. Under optimum conditions, linear calibration graphs were obtained from the AA, NE, and UA concentration ranges, which were 100-800 nM, 20-170 nM, and 40-175 nM, …
Influence Of Manganese Content On The Supercapacitive Performance Of Pbo$_{2}$-Mno$_{2}$ Electrodes, Yingwu Yao, Mengyao Li, Xinghua Zhang, Zunming Lu, Feng Wei
Influence Of Manganese Content On The Supercapacitive Performance Of Pbo$_{2}$-Mno$_{2}$ Electrodes, Yingwu Yao, Mengyao Li, Xinghua Zhang, Zunming Lu, Feng Wei
Turkish Journal of Chemistry
PbO$_{2}$-MnO$_{2}$ electrodes were prepared by electrochemical codeposition methods. The electrodes were characterized by scanning electron microscope, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The content of manganese in the electrodes increased with the increase in manganese ion concentration in the solution, which can reach 48.4%. The codeposition of manganese decreased the grain sizes and formed the porous structure. Cyclic voltammetry and galvanostatic charge-discharge measurements were used to evaluate the influence of manganese content in the electrodes on the specific capacitive performance of PbO$_{2}$-MnO$_{2}$ electrodes. The specific capacitance of PbO$_{2}$-MnO$_{2}$ (48.4%) electrodes could reach 374.5 F g$^{-1}$. The …
Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi
Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi
Turkish Journal of Chemistry
In this work, the electrochemical oxidation of deferasirox at a multiwall carbon nanotube paste electrode (MWCNTPE) was described. The electrochemical behavior of deferasirox was studied using cyclic voltammetry and chronoamperometry techniques and parameters such as charge transfer coefficient ($\alpha )$, the number of electrons involved in the rate-determining step ($n_{a})$, and diffusion coefficient ($D)$ were calculated. The capability of the electrode for the determination of deferasirox at low concentrations was investigated using the differential pulse voltammetry technique. It was found that the calibration graph of deferasirox was linear in the concentration range of 0.16-16.5 $\mu $M and its detection limit …
Removal Of Five Cationic Dyes Using A Resin Coated With Nickel/Nickel Boride Nanoparticles, Merve Çinar, Yasemi̇n İşlek Coşkun, Tüli̇n Deni̇z Çi̇ftçi̇
Removal Of Five Cationic Dyes Using A Resin Coated With Nickel/Nickel Boride Nanoparticles, Merve Çinar, Yasemi̇n İşlek Coşkun, Tüli̇n Deni̇z Çi̇ftçi̇
Turkish Journal of Chemistry
Resins coated with nickel/nickel boride nanoparticles were used to remove brilliant green, methyl violet, methylene blue, phenosafranine, and brilliant cresyl blue from water. The effects of pH, adsorbent dose, contact time, and initial dye concentration on the adsorption efficiencies were investigated. The point of zero charge for the adsorbent was pH 9.5. Isotherm studies were conducted using Langmuir, Freundlich, and Dubinin--Radushkevich models, and thermodynamic studies were also performed. Adsorption of the five dyes was found to obey the Langmuir isotherm model and was endothermic. The maximum adsorption capacities calculated from the Langmuir isotherm were 66.7, 88.5, 144.9, 56.2, and 147.1 …
Biological Evaluation And Synthesis Of New Pyrimidine-2(1h)-Ol/-Thiol Derivatives Derived From Chalcones Using The Solid Phase Microwave Method, Seda Fandakli, Nuran Kahri̇man, Tayyi̇be Beyza Yücel, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Biological Evaluation And Synthesis Of New Pyrimidine-2(1h)-Ol/-Thiol Derivatives Derived From Chalcones Using The Solid Phase Microwave Method, Seda Fandakli, Nuran Kahri̇man, Tayyi̇be Beyza Yücel, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Turkish Journal of Chemistry
Twenty-five new hydroxy- and methoxy-substituted 4,6-diarylpyrimidin-2(1H)-ol (20-34) and 4,6-diarylpyri\-midine-2(1H)-thiol derivatives (35-44) were synthesized from the reaction of the corresponding 1,3-diaryl-2-propene-1-one compounds (1-19) with urea or thiourea using the solid-phase microwave method. All the new synthetic compounds (20-44) were evaluated with regard to their $\alpha $-glucosidase activity. However, only compounds 22-25, 27,31,34, 35,37, and 40 exhibited a greater inhibitory effect than standard acarbose. The IC$_{50}$ values of the active compounds ranged between 2.36 and 13.34 $\mu $M. The 25 new compounds were also screened for their in vitro pancreatic lipase activity and compounds 20-27and 35-39 were found to be active. Of …
Physicochemical Characterization Of Different Cellulose Polymorphs/Graphene Oxide Composites And Their Antibacterial Activity, Sherif Mohamed Abdel Salam Keshk, Ibrahim Sayed Yahia
Physicochemical Characterization Of Different Cellulose Polymorphs/Graphene Oxide Composites And Their Antibacterial Activity, Sherif Mohamed Abdel Salam Keshk, Ibrahim Sayed Yahia
Turkish Journal of Chemistry
In order to investigate the interaction of graphene oxide (GO) with different cellulose polymorphs (I and II), we synthesized cellulose (I and II)/GO composites using the sonication method. Interestingly, no new peaks were observed in the FT-IR pattern of the cellulose (I and II)/GO composites, indicating that no chemical reactions took place between GO and cellulose. The X-ray diffraction patterns of cellulose I and II/GO composites were slightly different than those observed for cellulose I and II, indicating that some physical interactions occurred between the GO and cellulose. Unexpectedly the $d$-spacing values and the diffraction plane at the high-angle side …
Synthesis Of Quaternized Zinc(Ii) And Cobalt(Ii) Phthalocyanines Bearing Pyridine-2-Yl-Ethynyl Groups And Their Dna Binding Properties, Maryam Moeini Alishah, Hacer Yasemi̇n Yeni̇lmez, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Zehra Altuntaş Bayir
Synthesis Of Quaternized Zinc(Ii) And Cobalt(Ii) Phthalocyanines Bearing Pyridine-2-Yl-Ethynyl Groups And Their Dna Binding Properties, Maryam Moeini Alishah, Hacer Yasemi̇n Yeni̇lmez, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Zehra Altuntaş Bayir
Turkish Journal of Chemistry
The synthesis and biological properties of tetra-substituted zinc and cobalt phthalocyanines bearing ethynylpy- ridine units on the periphery and their quaternized derivatives have been reported. The binding of quaternized ZnPc and CoPc (Q-ZnPc and Q-CoPc) with calf thymus DNA was investigated by UV-Vis spectrophotometric methods and thermodynamics. The mixtures of Q-ZnPc or Q-CoPc and DNA solutions were used to determine the change in the thermal melting temperature of DNA with the thermal denaturation profile. Thermodynamic parameters that show the spontaneity of the reactions between DNA and the quaternized phthalocyanines were investigated. K$_{b}$ binding constants at a degree of 10$^{5}$ and …
Ligand Binding Constants Of The Cucurbit[7]Uril Predicted With Molecular Docking: A Theoretical Study, Balázs Roósz, Tamás Körtvélyesi, Béla Viskolcz
Ligand Binding Constants Of The Cucurbit[7]Uril Predicted With Molecular Docking: A Theoretical Study, Balázs Roósz, Tamás Körtvélyesi, Béla Viskolcz
Turkish Journal of Chemistry
A binding stability order predicting, molecular docking based fast technique was developed for host--guest complexes. Molecular descriptors were applied to ligand molecules to make the binding energy based docking scoring functions more efficient and reach the $\pm $0.50 log K unit theoretical precision for predictions. The goal of this work was to model complexes of cucurbit[7]uril (CB7) as a host molecule with different local anesthetics and choline and phosphonium choline molecules. The guest molecules were docked into the cavity of CB7. The binding free energy maps were correlated by Contact, Grid-Based, Hawkins GB/SA, and AMBER docking scores obtained from UCSF …
Schiff Base Of Isoniazid And Ketoprofen: Synthesis, X-Ray Crystallographic, Spectroscopic, Antioxidant, And Computational Studies, Naima Rehman, Muhammad Khalid, Moazzam Hussain Bhatti, Uzma Yunus, Ataualpa Albert Carmo Braga, Faiz Ahmed, Syed Muddassir Ali Mashhadi, Muhammad Nawaz Tahir
Schiff Base Of Isoniazid And Ketoprofen: Synthesis, X-Ray Crystallographic, Spectroscopic, Antioxidant, And Computational Studies, Naima Rehman, Muhammad Khalid, Moazzam Hussain Bhatti, Uzma Yunus, Ataualpa Albert Carmo Braga, Faiz Ahmed, Syed Muddassir Ali Mashhadi, Muhammad Nawaz Tahir
Turkish Journal of Chemistry
Ketoprofen and isoniazid together are a potential combination of a nonsteroidal antiinflammatory drug and an antitubercular medicine to treat tuberculosis and associated symptoms like fever and fatigue. The Schiff base of isoniazid with ketoprofen is synthesized in this research. Infrared spectroscopy (IR) and X-ray diffraction (XRD) analysis of the crystal packing proved the formation of the Schiff base and the existence of N-H$\cdot \cdot \cdot $O hydrogen bonds between the hydrogen-bonded dimer of the Schiff base. The complete geometrical optimization of the monomer and hydrogen-bonded dimer of the Schiff base is performed utilizing M06-2X/6-31G(d,p) level theory and compared with the …
$S$-Substituted Derivatives Of 1,2,4-Triazol-3-Thiol As New Drug Candidates For Type Ii Diabetes, Aziz Ur Rehman, Khadija Nafeesa, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Syed Adnan Ali Shah, Muhammad Ashraf, Muhammad Arif Lodhi, Farman Ali Khan, Bakht Jahan
$S$-Substituted Derivatives Of 1,2,4-Triazol-3-Thiol As New Drug Candidates For Type Ii Diabetes, Aziz Ur Rehman, Khadija Nafeesa, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Syed Adnan Ali Shah, Muhammad Ashraf, Muhammad Arif Lodhi, Farman Ali Khan, Bakht Jahan
Turkish Journal of Chemistry
The therapeutic applications of 1,2,4-triazoles motivated us to synthesize some new derivatives. Two series of $S$-substituted derivatives (8a-8j, 12a-12i) of 5-$\{$1-[(4-chlorophenyl)sulfonyl]-3-piperidinyl$\}$-4-phenyl-4$H$-1,2,4-triazol-3-thiol (6) have been synthesized and evaluated for their biological potential. Using 4-chlorobenzene sulfonyl chloride (1) and ethyl piperidine-3-carboxylate (2), ethyl 1-[(4-chlorophenyl)sulfonyl]piperidine-3-carboxylate (3) was synthesized and converted into 3,4,5-trisubstituted 1,2,4-triazole (6) through formation of the corresponding carbohydrazide (4) and hydrazinecarbothioamide (5). Compound 6 was transformed into 8a-8j by alkyl halides (7a-7j) and into 12a-12i by $N$-aralkyl/aryl-2-bromoacetamides (11a-11i) in an aprotic solvent. The electrophiles, 11a-11i, were synthesized by gearing up $N$-substituted aralkyl/aryl amines (10a-10i) with 2-bromoacetyl bromide (9) under dynamic pH …
Highly Efficient Catalytic Degradation Of Low-Density Polyethyleneusing A Novel Tungstophosphoric Acid/Kaolin Clay Composite Catalyst, Saira Attique, Madeeha Batool, Muhammad Irfan Jalees, Khurram Shehzad, Umar Farooq, Zakir Khan, Fawad Ashraf, Asma Tufail Shah
Highly Efficient Catalytic Degradation Of Low-Density Polyethyleneusing A Novel Tungstophosphoric Acid/Kaolin Clay Composite Catalyst, Saira Attique, Madeeha Batool, Muhammad Irfan Jalees, Khurram Shehzad, Umar Farooq, Zakir Khan, Fawad Ashraf, Asma Tufail Shah
Turkish Journal of Chemistry
In order to take advantage of the Bronsted acidity of tungstophosphoric acid (TPA) and Lewis acidity of kaolin, TPA-loaded kaolin catalysts with varying percentages of TPA (10-50 wt.-%) were prepared by wet impregnation method. Fourier transform infrared spectrometer, X-ray diffractometer, Brunauer-Emmett-Teller surface area analyzer, and scanning electron microscope characterizations were performed to confirm the successful loading of TPA on kaolin. Catalytic cracking of low-density polyethylene (LDPE), by employing TPA-loaded kaolin as the catalyst, produced a higher percentage of fuel oil (liquid and gaseous hydrocarbons) with a negligible amount of semisolid wax (1.0 wt.-%). The wax amount was significantly lower compared …
Synthesis And Characterization Of Novel Unsymmetrical Phthalocyanine/Tio$_{2}$ Composites And Their Evaluation As Photocatalysts For Degradation Of 4-Chlorophenol Under Visible Light, Yunus Alp Sütcüler, Görkem Gezek, Yaghub Mahmi̇ani̇, Altuğ Mert Sevi̇m
Synthesis And Characterization Of Novel Unsymmetrical Phthalocyanine/Tio$_{2}$ Composites And Their Evaluation As Photocatalysts For Degradation Of 4-Chlorophenol Under Visible Light, Yunus Alp Sütcüler, Görkem Gezek, Yaghub Mahmi̇ani̇, Altuğ Mert Sevi̇m
Turkish Journal of Chemistry
We prepared novel unsymmetrical A$_{3}$B-type zinc and cobalt phthalocyanines bearing monocarboxylic acid groups on peripheral positions using statistical condensation method, especially designed to anchor on the TiO$_{2}$ semiconductor surface. The novel complexes were anchored on TiO$_{2}$ semiconductor to prepare effective dye sensitized photoactive composites as heterogeneous catalysts. The results indicated that modified TiO$_{2}$ nanocrystals possessed only the anatase phase and MPc-TiO$_{2}$ photocatalysts with loading amount of dye ca. 8.27 $\mu $mol/g TiO$_{2}$ exhibit strong visible light absorption. Photocatalytic degradation of 4-chlorophenol (4-CP) under illumination with visible light ($\lambda >$ 400 nm) was tested with the composites prepared. The degradation profile …
Synthesis Of Some Ketones Via Nano-Nickel Oxide Catalyzed Acylation Of Arylzinc Reagents; Strategy Involving The Use Of Mixed (Methyl)(Aryl)Zincs, Özgen Ömür Pekel, Ender Erdi̇k, Meli̇ke Kalkan
Synthesis Of Some Ketones Via Nano-Nickel Oxide Catalyzed Acylation Of Arylzinc Reagents; Strategy Involving The Use Of Mixed (Methyl)(Aryl)Zincs, Özgen Ömür Pekel, Ender Erdi̇k, Meli̇ke Kalkan
Turkish Journal of Chemistry
Nano-NiO catalyzed acylation of mixed (methyl)(aryl)zincs with aromatic acyl halides in THF at room temperature provides a new facile route for aryl-aroyl coupling. Among NiCl$_{2}$.L$_{2}$ and NiCl$_{2}$.L (L = monodentate and bidentate phosphine ligand) catalysts, the lower catalyst loading of NiCl$_{2}$ (dppf) may seem attractive; however, nano-NiO, being the lowest cost catalyst, is more favorable for aroylation of (methyl)(aryl)zincs. This procedure also provides a supplement to Cu and Pd catalyzed acylation of diorganozincs.
Electrochemical Behavior And Voltammetric Determination Of Some Nitro-Substituted Benzamide Compounds, Özlem Sağlam, Ferah Cömert Önder, Tuğba Güngör, Mehmet Ay, Yusuf Di̇lgi̇n
Electrochemical Behavior And Voltammetric Determination Of Some Nitro-Substituted Benzamide Compounds, Özlem Sağlam, Ferah Cömert Önder, Tuğba Güngör, Mehmet Ay, Yusuf Di̇lgi̇n
Turkish Journal of Chemistry
Voltammetric behaviors of six nitro-substituted benzamides, which are potential prodrug candidates for nitroreductase-based cancer therapy, were investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The electrochemical behavior of aromatic nitro (ArNO$_{2})$ compounds by CV indicates that compounds involve various reduction/oxidation steps including the formation of aromatic nitro radical, nitroso, hydroxylamine, and amine groups. Applicability of the voltammetric determination of these prodrug candidates was studied by recording their DPVs, carried out in mixed media (Britton Robinson buffer solution $+$ DMF) at various pH values on a pencil graphite electrode (PGE). Results show that the PGE can offer a disposable, …
The First Synthesis And Antioxidant And Anticholinergic Activities Of 1-(4,5-Dihydroxybenzyl)Pyrrolidin-2-One Derivative Bromophenols Including Natural Products, Mohsen Rezai̇, Çeti̇n Bayrak, Parham Tasli̇mi̇, İlhami̇ Gülçi̇n, Abdullah Menzek
The First Synthesis And Antioxidant And Anticholinergic Activities Of 1-(4,5-Dihydroxybenzyl)Pyrrolidin-2-One Derivative Bromophenols Including Natural Products, Mohsen Rezai̇, Çeti̇n Bayrak, Parham Tasli̇mi̇, İlhami̇ Gülçi̇n, Abdullah Menzek
Turkish Journal of Chemistry
We report herein the first synthesis of biologically active natural bromophenols, namely 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)pyrrolidin-2-one (2), 2RS-1-(2,3-dibromo-4,5-dihydroxybenzyl)-5-oxopyrrolidine-2-carboxylic acid (3), and 2RS-methyl 1-(2,3-dibromo-4,5-dihydroxybenzyl)-5-oxopyrrolidine-2-carboxylate (4), along with their different derivatives (6 and 8-18). Among the synthesized compounds, , 4, and their derivatives (8 and 9) are yielded in racemic form. Radical scavenging assays of the synthesized molecules were investigated using various bioanalytical antioxidant methods including 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS$^{\bullet +})$ and 2,2-diphenyl-1-picrylhydrazyl (DPPH$^{\bullet })$. In addition, the reducing power of the novel bromophenols was investigated by Cu$^{2+}$-Cu$^{+}$ reducing, Fe$^{3+}$-Fe$^{2+}$ reducing, and [Fe$^{3+}$-(TPTZ)$_{2}$]$^{3+}$-[Fe$^{2+}$-(TPTZ)$_{2}$]$^{2+}$ reducing capacity and ferrous ions (Fe$^{2+})$ chelating abilities. The molecules demonstrated powerful …
Efficient Reductive Claisen Rearrangement Of Prop-2'-Enyloxyanthraquinones And 2'-Chloroprop-2'-Enyloxyanthraquinones With Iron Powder In Ionic Liquids, Samaneh Nadali, Ali Khoshroo, Ghasem Aghapour
Efficient Reductive Claisen Rearrangement Of Prop-2'-Enyloxyanthraquinones And 2'-Chloroprop-2'-Enyloxyanthraquinones With Iron Powder In Ionic Liquids, Samaneh Nadali, Ali Khoshroo, Ghasem Aghapour
Turkish Journal of Chemistry
A rapid and selective iron-mediated reductive Claisen rearrangement of various prop-2'-enyloxyanthraquinones and 2'-chloroprop-2'-enyloxyanthraquinones to 1-hydroxy-2-(prop-2'-enyl)anthraquinones and anthrafurandiones is presented. All reactions are carried out in a mixture of ionic liquids, [Bzmim]Cl (1-benzyl-3-methylimidazolium chloride) and [Hmim]BF$_{4}$ (1-methylimidazolium tetrafluoroborate), in short reaction times (5-35 min). Our study showed that 1-(prop-2'-enyloxy)anthraquinone is more active than 1-(2'-chloroprop-2'-enyloxy)anthraquinone to perform this rearrangement.
Synthesis, Solvatochromism, And Biological Activity Of Novel Azo Dyes Bearing 2-Pyridone And Benzimidazole Moieties, Dusan Mijin, Biljana Bozic Nedeljkovic, Bojan Bozic, Ilijana Kovrlija, Jelena Ladarevic, Gordana Uscumlic
Synthesis, Solvatochromism, And Biological Activity Of Novel Azo Dyes Bearing 2-Pyridone And Benzimidazole Moieties, Dusan Mijin, Biljana Bozic Nedeljkovic, Bojan Bozic, Ilijana Kovrlija, Jelena Ladarevic, Gordana Uscumlic
Turkish Journal of Chemistry
New azo dyes bearing 2-pyridone and benzimidazole moieties were prepared using diazotization of 4-(1H-benzo[d]imidazol-2-yl)aniline and coupling of the obtained diazonium salt with substituted 3-cyano-2-pyridones. Obtained compounds were characterized via UV-Vis, FT-IR, and $^{1}$H and $^{13}$C NMR spectroscopy as well as by elemental analysis data. The UV-Vis spectra of the synthesized dyes were measured in thirteen solvents of different properties at room temperature. Solvatochromism and tautomerism of novel azo dyes were discussed. An MTT (3,4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide) test was performed to prove the biocompatibility of the investigated dyes. The investigated dyes exhibited satisfying antiproliferative activities against both tumor cell lines, MDA-MB-231 …