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Full-Text Articles in Chemistry

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 Jan 2018

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, …


4d-Qsar Analysis And Pharmacophore Modeling For Alkynylphenoxyacetic Acids As Crth2 (Dp2) Receptor Antagonists, Semi̇ha Köprü, Emi̇n Saripinar Jan 2018

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 …


Neutral Atoms And Ion Energies, Accurate Ionization Potential, And Electron Affinities By Polynomial Generator Coordinate Hartree--Fock Method, Fernando Ratuchne, Ricardo Celeste Jan 2018

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 Jan 2018

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 …


Spectroscopic And Thermodynamic Approach To The Interaction Of Nonperipherally Substituted Cationic Phthalocyanines With Calf Thymus (Ct)-Dna, Sevgi̇can Tuncer, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Ayfer Kalkan Burat Jan 2018

Spectroscopic And Thermodynamic Approach To The Interaction Of Nonperipherally Substituted Cationic Phthalocyanines With Calf Thymus (Ct)-Dna, Sevgi̇can Tuncer, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Ayfer Kalkan Burat

Turkish Journal of Chemistry

Novel, nonperipherally tetrasubstituted cationic metal-free and metallophthalocyanines (Zn, In) were synthesized in the present study. The binding constants, the disappearance of quenching effect of all cationic phthalocyanines on the fluorescence intensity of SYBR Green--disodium salt of deoxyribonucleic acid (DNA) from calf thymus complex, and the changes in T$_{m}$ of double helix DNA with thermal denaturation profile were investigated by UV-Vis and fluorescence spectrophotometric methods. To investigate the spontaneity of the reactions between DNA and novel quaternized phthalocyanines in buffer, thermodynamic parameters were employed.


Exploring Inhibition Of Chemiluminescence Mechanisms With Fluorescence Quenching Studies And Interaction Energy Calculations, Zhenbo Liu, Tangmi Yuan, Yongming Liu, Wenzuo Li, Qingzhong Li, Bo Xiao, Jianbo Cheng Jan 2018

Exploring Inhibition Of Chemiluminescence Mechanisms With Fluorescence Quenching Studies And Interaction Energy Calculations, Zhenbo Liu, Tangmi Yuan, Yongming Liu, Wenzuo Li, Qingzhong Li, Bo Xiao, Jianbo Cheng

Turkish Journal of Chemistry

Carbamates weaken the luminol-H$_{2}$O$_{2}$ chemiluminescence (CL) catalyzed by sodium copper chlorophyll (SCC). The capacity to inhibit the CL of three carbamates is in the order of carbaryl (CBL) \textgreater carbofuran (CBF) \textgreater metolcarb (MTC). Mechanisms of carbamates inhibiting SCC-luminol-H$_{2}$O$_{2}$ CL are investigated using fluorescence quenching and quantum chemistry simulations for the first time in this work. Carbamate-SCC interactions studied using fluorescence spectroscopy show that with the increasing concentration of the SCC, the fluorescence of carbamate is quenched regularly, and the quenching mechanism is a static quenching process. Binding constants ($K_{B})$ of the three carbamates with SCC are CBL (4.39 x …


Synthesis And Cytotoxicity Evaluation Of [(2,4-Dichlorophenoxy)Methyl]-5-Aryl-1,3,4-Oxadiazole/4$H$-1,2,4-Triazole Analogues, Mohamed Jawed Ahsan Jan 2018

Synthesis And Cytotoxicity Evaluation Of [(2,4-Dichlorophenoxy)Methyl]-5-Aryl-1,3,4-Oxadiazole/4$H$-1,2,4-Triazole Analogues, Mohamed Jawed Ahsan

Turkish Journal of Chemistry

We report herein the synthesis, characterization, and cytotoxicity evaluations of some newer oxadiazole and triazole analogues (5a-j). The cytotoxicity of all the title compounds were evaluated as per the National Cancer Institute protocol in a one-dose assay (10 $\mu $M) on nine different panels of 59 cancer cell lines. 2-$\{$5-[(2,4-Dichlorophenoxy)methyl]-1,3,4-oxadiazol-2-yl$\}$phenol (5e) showed the maximum cytotoxicity among the series of ten compounds. The cytotoxicity of 5e was comparable to that of the standard anticancer drug, 5-fluorouracil, and better than that of imatinib. The structure activity relationship was also discussed.


Syntheses And Characterizations Of Cyclotriphosphazenes Containing A 4-Oxy-1-Naphthaldehyde Group, Hani̇fe İbi̇şoğlu, Esra Tanriverdi̇ Eçi̇k, Gönül Yeni̇lmez Çi̇ftçi̇ Jan 2018

Syntheses And Characterizations Of Cyclotriphosphazenes Containing A 4-Oxy-1-Naphthaldehyde Group, Hani̇fe İbi̇şoğlu, Esra Tanriverdi̇ Eçi̇k, Gönül Yeni̇lmez Çi̇ftçi̇

Turkish Journal of Chemistry

The nucleophilic substitution reaction of hexachlorocyclotriphosphazene (N$_{3}$P$_{3}$Cl$_{6}$, trimer) (1) with 4-hydroxy-1-naphthaldehyde (2) has been investigated for the first time. 4$^{{\prime}} $-Oxy-1$^{{\prime}} $-naphthaldehyde substituted mono- (3), bis- (4), and tris- (5) cyclotriphosphazenes were obtained from the nucleophilic substitution of compound 1 with 2 in a 1:2 molar ratio in the presence of Cs$_{2}$CO$_{3}$ in acetone at reflux. The pentakis-(6) and hexakis-substituted (7) cyclotriphosphazenes were prepared from the reaction of 1 with 2 in a 1:7 molar ratio using K$_{2}$CO$_{3}$ as a proton abstractor in tetrahydrofuran at room temperature. The structures of the new compounds (3-7) were determined by elemental analysis, FT-IR, …


New Triplet Silylenes M-Si-M$'$--X Along With Some Unusual Cyclic Forms (M = Li, Na, And K; M$'$ = Be, Mg, And Ca; X = F, Cl, And Br), Samaneh Ashenagar, Mohamad Zaman Kassaee Jan 2018

New Triplet Silylenes M-Si-M$'$--X Along With Some Unusual Cyclic Forms (M = Li, Na, And K; M$'$ = Be, Mg, And Ca; X = F, Cl, And Br), Samaneh Ashenagar, Mohamad Zaman Kassaee

Turkish Journal of Chemistry

Comparison of 54 M-Si--M$'$-X species is carried out using quantum mechanical ab initio and DFT computations at B3LYP/6-311$++$G**, QCISD(T)/6-311$++$G**, and CCSD(T)/6-311$++$G** levels of theory (M = Li, Na, K; M$'$ = Be, Mg, Ca, and X = F, Cl, Br). All triplet species with M = K appear more linear than their corresponding ones with Li and Na. The electronegativity reactivity descriptor for each halogen (X = F, Cl, Br) is used as a tool to evaluate the interrelated properties of these silylenes. Stability, assumed as singlet-triplet energy difference ($\Delta E_{S-T})$ for each series depends on the substituent's electropositivity, analyzed …


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 Jan 2018

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 …


Electrochemical Polymerization Of A New Alkoxy-Bridged Dithieno (3,2-B:2',3'-D) Pyrrole Derivative, Ari̇f Kivrak, Hüseyi̇n Beki̇r Yildiz, Selahatti̇n Gökyer, Buket Çarbaş Jan 2018

Electrochemical Polymerization Of A New Alkoxy-Bridged Dithieno (3,2-B:2',3'-D) Pyrrole Derivative, Ari̇f Kivrak, Hüseyi̇n Beki̇r Yildiz, Selahatti̇n Gökyer, Buket Çarbaş

Turkish Journal of Chemistry

A novel alkoxy-bridged dithieno (3, 2-B:2',3'-D) pyrrole (DTP) derivative was synthesized and its corresponding polymer poly(1,2-bis(2-(4H-dithieno[3,2-b:2',3'-d]pyrrol-4-yl)ethoxy)ethane) (P(DTP-alkoxy-DTP)) was successfully obtained electrochemically. The effects of alkoxy bridge in the structure on the electrochemical and spectroelectrochemical properties of the polymer were also investigated in detail. The results showed that the polymer film exhibits multielectrochromic behavior and a low band gap of 1.82 eV.


Recent Advances In Organ-On-A-Chip Technologies And Future Challenges: A Review, Hüseyi̇n Avci, Fatma Doğan Güzel, Sali̇m Erol, Ali̇ Akpek Jan 2018

Recent Advances In Organ-On-A-Chip Technologies And Future Challenges: A Review, Hüseyi̇n Avci, Fatma Doğan Güzel, Sali̇m Erol, Ali̇ Akpek

Turkish Journal of Chemistry

The significant development in the construction of microscale cell culture platforms and the interest in bioanalytical analysis have recently resulted in the emergence of a new concept of `organ-on-a-chip' systems. Organ-on-a-chip is a new three-dimensional (3D) in vitro microfabricated unit that contains a multichannel microfluidic cell culture. Even if many informative and useful data are obtained from animal models and in vitro assays, they are still limited for extrapolation to human systems during drug design and development. Only about 1 out of 10,000 compounds is processed in clinical trials for final approval. As being the first example of its kind, …


Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh Jan 2018

Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh

Turkish Journal of Chemistry

Superhydrophobic nanocomposite coatings for magnesium surfaces with remarkable corrosion resistance were fabricated by electrospinning in the presence of fluorosilane-functionalized silica (SiO$_{2})$ nanoparticles. The effects of surface-modified silica (mod-SiO$_{2})$ nanoparticles on the superhydrophobicity and corrosion resistance of polystyrene (PS)/mod-SiO$_{2}$ fiber coatings were evaluated. The incorporation of the SiO$_{2}$ nanoparticles endows PS fibers with rough surfaces exhibiting a water contact angle (WCA) of 165$^{\circ}$. The surface wettability, corrosion resistance, and their relation to the inorganic content in the PS fibers and the contact angle of the composite coatings were explored. Analysis of the corrosion results confirmed that the PS/mod-SiO$_{2}$ coating protected the …


Computational Investigation Of Intramolecular Reorganization Energy In Diketopyrrolopyrrole (Dpp) Derivatives, Şule Atahan Evrenk Jan 2018

Computational Investigation Of Intramolecular Reorganization Energy In Diketopyrrolopyrrole (Dpp) Derivatives, Şule Atahan Evrenk

Turkish Journal of Chemistry

Intramolecular reorganization energy (RE) of molecules derived from the diketopyrrolopyrrole (DPP) unit has been studied using B3LYP/6-31G(d,p) theory. It was found that the replacement of the oxygen atoms with sulfur in the DPP unit led to a smaller RE for both the hole and electron transfer processes. One disadvantage of the sulfur replacement is the twist of the conjugated backbone, which might impair the $\pi - \pi $ interactions in the solid state. The RE calculated from the adiabatic potential energy surfaces and that derived from the normal mode analysis agreed well for both systems. Electronic structure data showed that …


One-Pot Multicomponent Synthesis Of Piperidinium 3,3'-(Arylmethylene) Bis (2-Hydroxynaphthalene-1,4-Diones): Nmr Spectroscopic And X-Ray~Structure Characterization, Maryam Fatahpour, Nourollah Hazeri, Malek Taher Maghsoodlou, Fatemeh Noori Sadeh, Mojtaba Lshkari Jan 2018

One-Pot Multicomponent Synthesis Of Piperidinium 3,3'-(Arylmethylene) Bis (2-Hydroxynaphthalene-1,4-Diones): Nmr Spectroscopic And X-Ray~Structure Characterization, Maryam Fatahpour, Nourollah Hazeri, Malek Taher Maghsoodlou, Fatemeh Noori Sadeh, Mojtaba Lshkari

Turkish Journal of Chemistry

A facile synthesis of piperidinium 3,3'-(arylmethylene) bis (2-hydroxynaphthalene-1,4-dione) analogs as organic salts is described by the one-pot pseudo-four-component reaction between 2-hydroxy-1,4-naphthoquinone, aromatic aldehydes, and piperidine. The single-crystal X-ray diffraction analysis of these systems confirms that the stabilized predominant interactions are N-H\... O and O-H\... O hydrogen bonds. Mild and clean reaction conditions, high atom economy, and operational simplicity of this one-pot multicomponent reaction coupled with excellent yields and no need for column chromatography have transformed this procedure to be a superior synthetic route for the efficient formation of families of naphthoquinone-derived compounds.


One-Step Potentiostatic Codeposition And Electrochemical Studies Of Poly(1-Pyrenyl)-2,5-Di(2-Thienyl)Pyrrole-Co-Pyrrole) Film For Electrochemical Supercapacitors, Hakan Görçay, İlhami̇ Çeli̇k, Yücel Şahi̇n Jan 2018

One-Step Potentiostatic Codeposition And Electrochemical Studies Of Poly(1-Pyrenyl)-2,5-Di(2-Thienyl)Pyrrole-Co-Pyrrole) Film For Electrochemical Supercapacitors, Hakan Görçay, İlhami̇ Çeli̇k, Yücel Şahi̇n

Turkish Journal of Chemistry

In this paper, we report a simple, low-cost, and environmentally friendly electrochemical method to obtain a novel copolymer consisting of 1-pyrenyl-2,5-di(2-thienyl)pyrrole and pyrrole on a pencil graphite electrode (PGE). Poly(1-pyrenyl)-2,5-di(2-thienyl)pyrrole-co-pyrrole) that is P(PyrPy-co-Py) film was prepared by one-step potentiostatic codeposition in an ethanol solution containing PyrPy and Py monomers for supercapacitor applications. The electrodeposition of homopolymer and copolymer modified electrodes was carried out on the surface of the PGE via chronocoulometry. For comparison, P(Py)/PGE and P(PyrPy)/PGE were also electrochemically synthesized under the same reaction conditions. The surface morphologies of all the electrode materials were analyzed by field emission scanning electron …


The Interaction Between A Zinc(Ii) Phthalocyanine Compound Bearing Octakis Phenoxyacetamide Substituents And Calf Thymus Dna, Ali̇ Arslantaş, Mehmet Sali̇h Ağirtaş Jan 2018

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 Jan 2018

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 …


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 Jan 2018

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 …


Metal Nanoparticles/Carbon Nanotube Modified Electrodes For Voltammetric Determination Of Boron, Lokman Li̇v, Zekerya Dursun, Nuri̇ Naki̇boğlu Jan 2018

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 …


Synthesis And Antimicrobial And Antioxidant Activities Of Hybrid Molecules Containing Benzotriazole And 1,2,4-Triazole, Mahesh Chand, Reena Kaushik, Subhash Chand Jain Jan 2018

Synthesis And Antimicrobial And Antioxidant Activities Of Hybrid Molecules Containing Benzotriazole And 1,2,4-Triazole, Mahesh Chand, Reena Kaushik, Subhash Chand Jain

Turkish Journal of Chemistry

Eleven novel 1,2,4-triazolylbenzotriazoles have been prepared using 1-(hydrazinylcarbonylmethyl)-1$H$-benzot- riazole (3) as a potent intermediate. Compound 3, however, was obtained from benzotriazole in two steps. All synthesized compounds were characterized by detailed spectral studies like IR, $^{1}$H NMR, $^{13}$C NMR, and mass spectrometry. All synthesized compounds were evaluated for their \textit{in vitro} antimicrobial activity against seven strains of bacteria and four strains of fungi. Compounds 13, 17, 19, 20, and 21}were found to possess antibacterial activity comparable to that of ciprofloxacin against a Klebsiella pneumoniae strain. Except for compounds2 and 13, all compounds showed good antifungal activity against an Aspergillus niger …


Voltammetric Determination Of Glycopyrrolate In A Pharmaceutical Formulation, Muneer Fadr, Abdulaziz Nabil Amro, Sami Ben Aoun, Samer Ratrout, Fadi Asfour Jan 2018

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 …


Determination Of Hydrogen Peroxide With An Enzymeless Amperometric Sensor Based On Poly(Vinylferrocene)-Supported Ag Nanoparticles, Mutlu Sönmez Çelebi̇, Kübra Öztürk, Mehmet Dumangöz, Fi̇li̇z Kuralay Jan 2018

Determination Of Hydrogen Peroxide With An Enzymeless Amperometric Sensor Based On Poly(Vinylferrocene)-Supported Ag Nanoparticles, Mutlu Sönmez Çelebi̇, Kübra Öztürk, Mehmet Dumangöz, Fi̇li̇z Kuralay

Turkish Journal of Chemistry

An enzymeless electrochemical sensor for detection of low amounts of H$_{2}$O$_{2}$ with the aid of Ag nanoparticles supported on conducting poly(vinylferrocene) (PVF) film was developed. Experimental results revealed that contribution of Ag nanoparticles led to remarkable improvement by means of reduction potential and reduction current. Influence of experimental parameters (i.e. polymeric film thickness, concentration of Ag precursor, immersion time in precursor solution, reduction time, and reduction potential) were investigated. The Ag/PVF-modified electrode system was characterized physically by scanning electron microscopy. The results revealed that the sensor developed was easy-to-prepare, economic, selective, and sensitive, with a fast response time of 3 …


Simultaneous Determination Of Azithromycin And Levooxacin In Pharmaceuticalsby Charge Transfer Complexation With Alizarin Red S Using An Absorption-Factormethod, Vijay D. Chavada, Nejal M. Bhatt, Mallika Sanyal, Pranav S. Shrivastav Jan 2018

Simultaneous Determination Of Azithromycin And Levooxacin In Pharmaceuticalsby Charge Transfer Complexation With Alizarin Red S Using An Absorption-Factormethod, Vijay D. Chavada, Nejal M. Bhatt, Mallika Sanyal, Pranav S. Shrivastav

Turkish Journal of Chemistry

A new approach based on a selective charge transfer reaction with alizarin red S is described for the simultaneous determination of azithromycin and levo oxacin in their binary mixtures using an absorption-factor spectrophotometric method. Native absorbance was used for the determination for levo oxacin, while a charge transfer complexation of alizarin red S served as the basis for the quantitation of azithromycin. The reaction of azithromycin with alizarin red S was possible in methanol under neutral conditions within 15 min at 25 ℃. The conditions were suitably optimized for selective complexation of azithromycin with minimal interference from levo oxacin. The …


Gas Permeability Of Polydimethylsiloxane Membranes Lled With Clinoptilolite Indifferent Cationic Forms, Çi̇ğdem Atalay-Oral Jan 2018

Gas Permeability Of Polydimethylsiloxane Membranes Lled With Clinoptilolite Indifferent Cationic Forms, Çi̇ğdem Atalay-Oral

Turkish Journal of Chemistry

Zeolite-polymer mixed matrix membranes were prepared by lling polydimethylsiloxane (PDMS) with clinop- tilolite in various cationic forms of K, Mg, H, and Na. The membranes were characterized by scanning electron microscopy as well as measurements of O$_{2}, $N$_{2}$ and CO$_{2}$ gas permeabilities. The results indicated the presence of an optimum zeolite loading in the mixed matrix membranes maximizing permeability. The type of the cationic form of clinoptilolite used affected the permeabilities and ideal selectivities of the zeolite-polymer mixed matrix membranes investigated to some degree and some improvements were obtained when compared to the ideal selectivities of the original polymeric membranes.


Experimental And Theoretical Studies Of Carbazole-Based Schiff Base As A Fluorescent Fe$^{3+}$ Probe, Hakan Kandemi̇r, Abdulkadi̇r Koçak, Süreyya Oğuz Tümay, Bünyemi̇n Çoşut, Yunus Zorlu, İbrahi̇m Fazil Şengül Jan 2018

Experimental And Theoretical Studies Of Carbazole-Based Schiff Base As A Fluorescent Fe$^{3+}$ Probe, Hakan Kandemi̇r, Abdulkadi̇r Koçak, Süreyya Oğuz Tümay, Bünyemi̇n Çoşut, Yunus Zorlu, İbrahi̇m Fazil Şengül

Turkish Journal of Chemistry

Synthesis of a new (E)-N1-((9-ethyl-9H-carbazol-3-yl)methylene)-5-nitrobenzene-1,2-diamine as a fluorescent chemosensor for selective detection of Fe$^{3+}$ ion over a number of other metal ions is described. The method for the synthesis of the carbazole Schiff base was based on the condensation of carbazole-3-carbaldehyde with 4-nitro-o-phenyldiamine in dimethylformamide in a moderate yield. The structure of the final compound was characterized by $^{1}$H NMR, $^{13}$C NMR, IR, mass spectrometry, and single crystal X-ray diffraction. The final compound exhibited exceptional selective and sensitive turn-on fluorescence response to the Fe$^{3+}$ cation. The fluorescent intensity of the final compound was increased 20-fold and the stoichiometry ratio of …


Simultaneous Determination Of Copper(Ii) And Zinc(Ii) Via Simple Acid-Base Titrimetry Using Glass Ph Electrode, Emi̇ne Gül Cansu Ergün, Adnan Kenar Jan 2018

Simultaneous Determination Of Copper(Ii) And Zinc(Ii) Via Simple Acid-Base Titrimetry Using Glass Ph Electrode, Emi̇ne Gül Cansu Ergün, Adnan Kenar

Turkish Journal of Chemistry

The combination of potentiometric methods with multivariate calibration techniques allows complex mixtures to be analyzed. In this study, a new method was developed and reported for simultaneous determination of copper(II) and zinc(II) cations in a mixture by titrimetric methods. The developed method permits simultaneous cation analysis with low detection limits, just by using a pH electrode. This work has achieved the challenging goal of developing a cost-effective and applicable method that can be applied in most laboratories due to independence of any chemical instruments. Partial least squares 1, one of the multivariate calibration techniques, was used in the analysis of …


Synthesis And Characterization Of New Thiophene--Benzimidazole-Based Electrochromes, Emi̇ne Gül Cansu Ergün Jan 2018

Synthesis And Characterization Of New Thiophene--Benzimidazole-Based Electrochromes, Emi̇ne Gül Cansu Ergün

Turkish Journal of Chemistry

In the present study, two new donor--acceptor--donor-type molecules were synthesized and the electro-optical properties of the resulting monomers and their corresponding polymers were investigated. Thiophene was selected as the donor unit and cycloheptyl- and cyclooctyl- substituted benzimidazoles were used as the acceptor units. The synthesized monomers and their electrochemically obtained polymers were characterized using cyclic voltammetry and UV-Vis spectrometry. The optical band gap values of the polymers were 1.62 eV and the polymer films changed color to gray upon oxidation, while they were brick red in their neutral states. Moreover, changing the ring size on the acceptor group from seven …


Adsorptive Properties Of Mesoporous Silica Modified With Lewis Base Molecule And Its Application In The Preconcentration Of Cu(Ii), Co(Ii), And Cd(Ii) From Aqueous Media, Janaíne Do Rócio Ivassechen, Alexandre De Oliveira Jorgetto, Marcos Henrique Pereira Wondracek, Adrielli Cristina Peres Da Silva, Luiz Fabrício Zara, Valber De Albuquerque Pedrosa, Bruno Prior Rocha, Margarida Juri Saeki, Gustavo Rocha Castro Jan 2018

Adsorptive Properties Of Mesoporous Silica Modified With Lewis Base Molecule And Its Application In The Preconcentration Of Cu(Ii), Co(Ii), And Cd(Ii) From Aqueous Media, Janaíne Do Rócio Ivassechen, Alexandre De Oliveira Jorgetto, Marcos Henrique Pereira Wondracek, Adrielli Cristina Peres Da Silva, Luiz Fabrício Zara, Valber De Albuquerque Pedrosa, Bruno Prior Rocha, Margarida Juri Saeki, Gustavo Rocha Castro

Turkish Journal of Chemistry

Cocondensation and postfunctionalization methods were employed to synthesize a mesoporous silica with large surface area (795.1 $\pm $ 1.1 m$^{2}$ g$^{-1})$ modified with 4-amino-5-hydrazino-1,2,4-triazole-3-thiol, which was successfully applied to adsorb and preconcentrate Cu(II), Co(II), and Cd(II) from aqueous media. Infrared spectroscopy of the adsorbent material demonstrated N-H stretching bonds related to primary amines existing in the ligand molecule, elemental analysis revealed the presence of 0.132 mmol g$^{-1}$ of nitrogen, scanning electron microscopy indicated globularly shaped particles with average size of 10 $\mu $m, and the point of zero charge was found to be 7.2. Kinetic data were applied to the …


Photocatalytic Degradation Of The Herbicide Quinclorac In Water Using Mn (Iii) Salen And Solar Light, Yisi Yang, Yan Zhang, Qingru Zeng Jan 2018

Photocatalytic Degradation Of The Herbicide Quinclorac In Water Using Mn (Iii) Salen And Solar Light, Yisi Yang, Yan Zhang, Qingru Zeng

Turkish Journal of Chemistry

Quinclorac (QNC) is a widely used herbicide and is persistent in surface and ground waters. Its residuals and converted products are hazardous to aquatic animals, vegetation, and microbes, and it is therefore important to degrade QNC using an efficient and environmental friendly technology. In this study, the photocatalytical degradation of QNC using [(R,R)-(N,N$'$-bis(3,5,3$'$,5$'$-tetra-tert-butylsalicylidene)-1,2-cyclohexanediaminato] manganese(III) acetate (Mn (III) salen) and H$_{2}$O$_{2}$ was performed under natural sunlight irradiation and a 91% degradation rate was achieved in neutral pure water in 240 min. The identified degradation products confirmed that the cleavage of QNC molecules was the main process involved in the hydroxylation, along …