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Photochromic And Fluorescence Properties Of Coumarin Fulgimides, Khamis Nassor Ally, Leyla Öztürk, Mahmut Köse
Photochromic And Fluorescence Properties Of Coumarin Fulgimides, Khamis Nassor Ally, Leyla Öztürk, Mahmut Köse
Turkish Journal of Chemistry
Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation.
Characterization, Mechanical, And Antibacterial Properties Of Nanofibers Derived From Olive Leaf, Fumitory, And Terebinth Extracts, Ni̇lşen Sünter Eroğlu, Suat Canoğlu, Meti̇n Yüksek
Characterization, Mechanical, And Antibacterial Properties Of Nanofibers Derived From Olive Leaf, Fumitory, And Terebinth Extracts, Ni̇lşen Sünter Eroğlu, Suat Canoğlu, Meti̇n Yüksek
Turkish Journal of Chemistry
In this study, nanofiber structures were obtained with convenient polymers (PVA [polyvinyl alcohol] and PCL [poly º-caprolactone]) derived from the herbal extracts of olive leaves, fumitory, and terebinth plants. Optimum nanofiber structures were identified by measuring viscosity and conductivity values and performing morphological analysis, characterization, and mechanical tests of the prepared solutions. The potential use for wound healing at the most efficient level was determined as a result of antibacterial analysis of the structures obtained. APT (PVA/terebinth) and BFO (PCL/fumitory) nanofibers had the thinnest diameter range and the highest strength values. In terms of the determination of antibacterial effects, nanofiber …
Synthesis And Bioactivities Of 1-(4-Hydroxyphenyl)-2-((Heteroaryl)Thio)Ethanones As Carbonic Anhydrase I, Ii And Acetylcholinesterase Inhibitors, Cem Yamali, Hali̇se İnci̇ Gül, Yeli̇z Demi̇r, Cavi̇t Kazaz, İlhami̇ Gülçi̇n
Synthesis And Bioactivities Of 1-(4-Hydroxyphenyl)-2-((Heteroaryl)Thio)Ethanones As Carbonic Anhydrase I, Ii And Acetylcholinesterase Inhibitors, Cem Yamali, Hali̇se İnci̇ Gül, Yeli̇z Demi̇r, Cavi̇t Kazaz, İlhami̇ Gülçi̇n
Turkish Journal of Chemistry
The discovery of enzyme targeting inhibitors is a popular area of drug research. Biological activities of the compounds bearing phenol and heteroaryl groups make them popular groups in drug design targeting important enzymes such as acetylcholinesterase (AChE, E.C.3.1.1.7) and carbonic anhydrases (CAs, EC 4.2.1.1). 1-(4-hydroxyphenyl)-2-((aryl)thio)ethanones as possible AChE and CAs inhibitors were synthesized, and their chemical structures were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, and HRMS. The compounds 2 and 4 were found potent AChE inhibitors with the Ki values of 22.13 ± 1.96 nM and 23.71 ± 2.95 nM, respectively, while the compounds 2 (Ki $=$ 8.61 ± …
In Silico Adme Predictions And In Vitro Antibacterial Evaluation Of 2-Hydroxy Benzothiazole-Based 1,3,4-Oxadiazole Derivatives, Afnan Ahmed Alghamdi, Mohammad Mahboob Alam, Syed Nazreen
In Silico Adme Predictions And In Vitro Antibacterial Evaluation Of 2-Hydroxy Benzothiazole-Based 1,3,4-Oxadiazole Derivatives, Afnan Ahmed Alghamdi, Mohammad Mahboob Alam, Syed Nazreen
Turkish Journal of Chemistry
In the present work, a library of fifteen 2-hydroxy benzothiazole-linked 1,3,4 -oxadiazole derivatives have been synthesized and confirmed using different analytical techniques. All of the synthesized compounds have been tested for antibacterial and in silico pharmacokinetic studies for the first time. From the ADME predictions, compound 4 showed the highest in silico absorption percentage (86.77%), while most of the compounds showed more than 70% absorption. All of the compounds comply with the Lipinski rule of 5, suggesting that the compounds possess good drug likeness properties upon administration. Furthermore, all of the compounds follow the Veber rule, indicating good bioavailability and …
New Protocols For The Synthesis Of 5-Amino-7-(4-Phenyl)-4,7-Dihydro-[1,2,4]Triazolo[1,5-A]Pyrimidine-6-Carboxylate Esters Using An Efficient Additive, Nader Ghaffari Khaligh, Taraneh Mihankah, Salam Titinchi, Zohreh Shahnavaz, Mohd Rafie Johan
New Protocols For The Synthesis Of 5-Amino-7-(4-Phenyl)-4,7-Dihydro-[1,2,4]Triazolo[1,5-A]Pyrimidine-6-Carboxylate Esters Using An Efficient Additive, Nader Ghaffari Khaligh, Taraneh Mihankah, Salam Titinchi, Zohreh Shahnavaz, Mohd Rafie Johan
Turkish Journal of Chemistry
This work introduces a new additive named 4,4'-trimethylenedipiperidine for the practical and ecofriendly preparation of ethyl 5-amino-7-(4-phenyl)-4,7-dihydro-[1,2,4]triazolo[1,5-$a$]pyrimidine-6-carboxylate derivatives. This chemical is commercially available and easy to handle. It also possesses a low melting point and a broad liquid range temperature, high thermal stability, and good solubility in water. Based on green chemistry principles, the reaction was performed in a) a mixture of green solvents i.e. water and ethanol (1:1 v/v) at reflux temperature, and b) the additive was liquefied at 65 $^{\circ}$C and the reaction was conducted in the liquid state of the additive. High yields of the desired triazolo-pyrimidines …
Preparation, Structure Elucidation, And Antioxidant Activity Of New Bis(Thiosemicarbazone) Derivatives, Hasan Yakan
Preparation, Structure Elucidation, And Antioxidant Activity Of New Bis(Thiosemicarbazone) Derivatives, Hasan Yakan
Turkish Journal of Chemistry
Schiff-base-bearing new bis(thiosemicarbazone) derivatives were prepared from terephthalaldehyde and various thiosemicarbazides. FT--IR,$^{\, 1}$H NMR, $^{13}$C NMR, and UV--Vis spectroscopic methods and elemental analysis were used to elucidate the identification of the synthesized molecules. The in vitro antioxidant activity of the synthesized compounds was analysed with the 1,1-diphenyl-2-picryl hydrazyl free-radical-trapping process. The synthesized compounds exhibited lower antioxidant activity than the standard ascorbic acid. IC$_{50}$ values of the synthesized molecules measured from 3.81 $\pm $ 0.01 to 29.05 $\pm $ 0.11 $\mu$M. Among the synthesized compounds, compound 3 had the best antioxidant activity. Moreover, this study explained the structure--activity relationship of the …
New Sandwich-Type Polymeric Potassium-Dicyanoargentate(I) Complex: Synthesis, Characterization And Enzymatic Activity, Nesri̇n Korkmaz
New Sandwich-Type Polymeric Potassium-Dicyanoargentate(I) Complex: Synthesis, Characterization And Enzymatic Activity, Nesri̇n Korkmaz
Turkish Journal of Chemistry
Coordination compounds containing dicyanoargentate(I) have remarkable biological potential due to their therapeutic antibacterial, antifungal, antibiofilm, and anticancer properties. In this study, a new dicyanoargentate(I)-based complex was synthesized and characterized by various procedures (elemental, thermal, FT-IR for complex) involving crystal analysis of the complex. In addition, the biological activity of this new compound on the acetylcholinesterase (AChE) enzyme, an important enzyme for the nervous system, was investigated. When the infrared (IR) spectrum of the complex is examined, the OH vibration peak resulting from H$_{2}$O molecules in the structure at 3948-3337 cm$^{-1}$ and at 2138 cm$^{-1}$, along with a CN peak coordinated …
Voltammetric Determination Of Itopride Using Carbon Paste Electrode Modified With Gd Doped Tio$_{2}$Nanotubes, Abdulaziz Nabil Amro, Khadijah Emran, Hessah Alanazi
Voltammetric Determination Of Itopride Using Carbon Paste Electrode Modified With Gd Doped Tio$_{2}$Nanotubes, Abdulaziz Nabil Amro, Khadijah Emran, Hessah Alanazi
Turkish Journal of Chemistry
In the present work TiO$_{2}$ nanotubes (TNT) have been synthesized by alkaline hydrothermal transformation. Then they have been doped with Gd element. Characterizations of doped and undoped TNT have been done with TEM and SEM. The chemical composition was analyzed by EDX, Raman and FTIR spectroscopy. The crystal structure was characterized by XRD. Carbon paste electrode has been fabricated and mixed with Gd doped and undoped TNT to form a nanocomposite working electrode. Comparison of bare carbon paste electrode and Gd doped and undoped TNT carbon paste electrode for 1.0 × 10$^{-3}$ M K$_{4\, }$[Fe(CN)$_{6}$] voltammetric analysis; it was observed …
A Comparative Study On The Monovalent And Divalent Cation Separation Of Polymeric Films And Membranes From Salt Solutions Under Diffusion-Dialysis, Serkan Acar, Hacer Yeşi̇m Cengi̇z, Ayça Ergün, Eymen Konyali, Hüseyi̇n Deli̇göz
A Comparative Study On The Monovalent And Divalent Cation Separation Of Polymeric Films And Membranes From Salt Solutions Under Diffusion-Dialysis, Serkan Acar, Hacer Yeşi̇m Cengi̇z, Ayça Ergün, Eymen Konyali, Hüseyi̇n Deli̇göz
Turkish Journal of Chemistry
This study deals with selective separation of mono- and divalent cations from aqueous salt solutions using polymeric films based on polyethylene (PE) and polyamide6 (PA6), and two different commercial nanofiltration (NF) membranes. The diffusion rates (D) of ions (Na$^{+}$ and Ca$^{2+})$, separation factors ($\alpha )$ and ion rejections (R) of the films and NF membranes are examined comparatively as well as their surface morphology and hydrophilicity. It is observed that the diffusion rates of Na$^{+}$are in the range of 0.7-1.8 $\times $ 10$^{-8}$cm$^{2}$.s$^{-1\, }$in the decreasing order of PE $>$ NF90 $>$ NF270 $>$ PA6 while Ca$^{2+\, …
Fluorescent Sensing Platform For Low-Cost Detection Of Cu$^{\Mathbf{2+}}$ By Coumarin Derivative: Dft Calculation And Practical Application In Herbal And Black Tea Samples, Tahi̇r Savran, Abdurrahman Karagöz, Şükri̇ye Ni̇han Karuk Elmas, Duygu Aydin, Furkan Özen, Kenan Koran, Fatma Nur Arslan, Ahmet Orhan Görgülü, İbrahi̇m Yilmaz
Fluorescent Sensing Platform For Low-Cost Detection Of Cu$^{\Mathbf{2+}}$ By Coumarin Derivative: Dft Calculation And Practical Application In Herbal And Black Tea Samples, Tahi̇r Savran, Abdurrahman Karagöz, Şükri̇ye Ni̇han Karuk Elmas, Duygu Aydin, Furkan Özen, Kenan Koran, Fatma Nur Arslan, Ahmet Orhan Görgülü, İbrahi̇m Yilmaz
Turkish Journal of Chemistry
A fluorogenic probe based on a coumarin-derivative for Cu$^{2+}$ sensing in CH$_{3}$CN/H$_{2}$O media (v/v, 95/5, 5.0 \textmu M) was developed and applied in real samples. 3-(4-chlorophenyl)-6,7-dihydroxy-coumarin (MCPC) probe was obtained by synthetic methodologies and identified by spectral techniques. The probe MCPC showed remarkable changes with a ``turn-off'' fluorogenic sensing approach for the monitoring of Cu$^{2+}$ at 456 nm under an excitation wavelength of 366 nm. The response time of the probe MCPC was founded as only 1 min. The detection limit of the probe MCPC was recorded to be 1.47 nM. The binding constant and possible stoichiometric ratio (1:1) values …
Bis Benzothiophene Schiff Bases: Synthesis And In Silico-Guided Biological Activity Studies, Yasemi̇n Ünver, Di̇lek Ünlüer, Şahi̇n Di̇rekel, Serdar Durdaği
Bis Benzothiophene Schiff Bases: Synthesis And In Silico-Guided Biological Activity Studies, Yasemi̇n Ünver, Di̇lek Ünlüer, Şahi̇n Di̇rekel, Serdar Durdaği
Turkish Journal of Chemistry
Since benzo [$b$] thiophene scaffold is one of the privileged structures in drug discovery as this core exhibitsactivities for different biological problems, in this study bis (benzo[$b$]thiophene-2-yl) alkyl methanimine derivatives (1-9) were synthesized by reacting benzo[$b$]thiophene-2-carbaldehyde with diamines. All newly compounds were characterized by IR, $^{1}$H NMR and $^{13}$C NMR spectroscopic methods. Synthesized compounds were investigated using binary QSAR-based models on therapeutic activity prediction of synthesized compounds and they showed high predicted activities in following diseases: bacterial, angina, allergy, depression and obesity. Thus, they were then tested for their antimicrobial and antileishmanial activities as a result of this theoretical study. …
Synthesis, Biological Evaluation Of Antioxidant-Antibacterial Activities And Computational Studies Of Novel Anthracene- And Pyrene-Based Schiff Base Derivatives, Ayşegül Gümüş, Veysi̇ Okumuş, Selçuk Gümüş
Synthesis, Biological Evaluation Of Antioxidant-Antibacterial Activities And Computational Studies Of Novel Anthracene- And Pyrene-Based Schiff Base Derivatives, Ayşegül Gümüş, Veysi̇ Okumuş, Selçuk Gümüş
Turkish Journal of Chemistry
Schiff base derivatives with anthracene- and pyrene-based units, A1-A6 and P1-P6 were synthesized (89%-99% yields). Schiff base derivatives were designed to possess an heterocyclic moiety on one side to enhance the coordination ability towards metals. To investigate the biological assay of the newly synthesized compounds, their DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, metal chelating, reducing power, antibacterial and DNA binding activities were tested. A6 (63.1%) showed the maximum free radical scavenging activity among all. However, compound P3 at concentration of 200 \textmu g/mL possessed the highest metal chelating (45.8%) activity and power of reduction. In addition, P3 and A6 showed antibacterial activity …
A Novel Proton-Exchange Porous Silicon Membrane Production Method For \Textmu Dmfcs, Meltem Gör Bölen, Tevhi̇t Karacali
A Novel Proton-Exchange Porous Silicon Membrane Production Method For \Textmu Dmfcs, Meltem Gör Bölen, Tevhi̇t Karacali
Turkish Journal of Chemistry
This study introduces a new production method to use as a porous silicon-based proton exchange membrane for μDMFCs. In this respect, EIS, fuel crossover test, and fuel cell performance test at the μDMFC sample cell are performed at room temperature on a porous silicon-based membrane that was produced for passive mode μDMFC as a proton exchange membrane. The reason for performing the fuel crossover test is to ensure the silicon opened pores along the silicon wafer and to examine the fuel permeability of the membrane. The fuel crossover test shows that the fuel cell provides energy for about 60 min …
Effect Of Mg Doping On Morphology, Photocatalytic Activity And Related Biological Properties Of Zn$_{\Mathbf{1-X}}$ Mg$_{X}$ O Nanoparticles, Bestenur Yalçin, Doğan Akcan, İbrahi̇m Ertuğrul Yalçin, Mehmet Can Alphan, Kenan Şentürk, İbrahi̇m İlker Özyi̇ği̇t, Lütfi̇ Arda
Effect Of Mg Doping On Morphology, Photocatalytic Activity And Related Biological Properties Of Zn$_{\Mathbf{1-X}}$ Mg$_{X}$ O Nanoparticles, Bestenur Yalçin, Doğan Akcan, İbrahi̇m Ertuğrul Yalçin, Mehmet Can Alphan, Kenan Şentürk, İbrahi̇m İlker Özyi̇ği̇t, Lütfi̇ Arda
Turkish Journal of Chemistry
The objective of this study is to synthesize ZnO and Mg doped ZnO (Zn$_{1-x}$Mg$_{x}$O) nanoparticles via the sol-gel method, and characterize their structures and to investigate their biological properties such as antibacterial activity and hemolytic potential.Nanoparticles (NPs) were synthesized by the sol-gel method using zinc acetate dihydrate (Zn(CH$_{3}$COO)$_{2}$.2H$_{2}$O) and magnesium acetate tetrahydrate (Mg(CH$_{3}$COO)$_{2}$.4H$_{2}$O) as precursors. Methanol and monoethanolamine were used as solvent and sol stabilizer, respectively. Structural and morphological characterizations of Zn$_{1-x}$Mg$_{x}$O nanoparticles were studied by using XRD and SEM-EDX, respectively. Photocatalytic activities of ZnO and selected Mg-doped ZnO (Zn$_{1-x}$Mg$_{x}$O) nanoparticles were investigated by degradation of methylene blue (MeB). Results …
Water Management Improvement In Pem Fuel Cells Via Addition Of Pdms Or Aptespolymers To The Catalyst Layer, Hande Ungan, Ayşe Bayrakçeken Yurtcan
Water Management Improvement In Pem Fuel Cells Via Addition Of Pdms Or Aptespolymers To The Catalyst Layer, Hande Ungan, Ayşe Bayrakçeken Yurtcan
Turkish Journal of Chemistry
Water management is one of the obstacles in the development and commercialization of proton exchange membrane fuel cells (PEMFCs). Sufficient humidification of the membrane directly affects the PEM fuel cell performance. Therefore, 2 different hydrophobic polymers, polydimethylsiloxane (PDMS) and (3-Aminopropyl) triethoxysilane (APTES), were tested at different percentages (5, 10, and 20 wt.%) in the catalyst layer. The solution was loaded onto the surface of a 25 BC gas diffusion layer (GDL) via the spraying method. The performance of the obtained fuel cells was compared with the performance of the commercial catalyst. Characterizations of each surface, including different amounts of PDMS …
A Road Map To Assess Critical Materials Content In Boron Industrial Wastes Usingsustainable Micro-X-Ray Fluorescence And Total Reflection X-Ray Fluorescenceinstrumentation, İbrahi̇m Kula, Christian Gutsche, Yunus Erdoğan, Andreas Fittschen, Ursula Elisabeth Adriane Fittschen
A Road Map To Assess Critical Materials Content In Boron Industrial Wastes Usingsustainable Micro-X-Ray Fluorescence And Total Reflection X-Ray Fluorescenceinstrumentation, İbrahi̇m Kula, Christian Gutsche, Yunus Erdoğan, Andreas Fittschen, Ursula Elisabeth Adriane Fittschen
Turkish Journal of Chemistry
Turkey is the leading country in the world in terms of boron production and sale. Increasing boron production goes along with an increasing generation of boron wastes. The pollution of the soil and the air around the waste piles, as well as the occupation of several square kilometers of ground, are major environmental problems. It is, therefore, very important to make use of the wastes to both protect the environment and create revenue. This work presenteda road map for fast screening of boron waste for critical elements followed by determination of the elements using small footprint low power instrumentation. The …
A Novel Selective Fluorescent Chemosensor For Fe$^{3+}$ Ions Based On Phthalonitrile Dimer:Synthesis, Analysis, And Theoretical Studies, Shaya Al-Raqa, İpek Ömeroğlu, Doğan Erbahar, Mahmut Durmuş
A Novel Selective Fluorescent Chemosensor For Fe$^{3+}$ Ions Based On Phthalonitrile Dimer:Synthesis, Analysis, And Theoretical Studies, Shaya Al-Raqa, İpek Ömeroğlu, Doğan Erbahar, Mahmut Durmuş
Turkish Journal of Chemistry
Phenyl-4,4-di(3,6-dibutoxyphthalonitrile) (3) was synthesized by the reaction of 1,4-phenylenebisboronic acid (1) and 4-bromo-3,6-dibutoxyphthalonitrile (2), using Suzuki cross-coupling reaction. The newly synthesized compound (3) was characterized by FT-IR, MALDI-MS, ESI-MS, $^{1}$H-NMR, $^{13}$C-NMR, and $^{13}$C-DEPT-135-NMR. The fluorescence property of phenyl-4,4-di(3,6- dibutoxyphthalonitrile) (3) towards various metal ions was investigated by fluorescence spectroscopy, and it was observed thatthe compound (3) displayed a significantly `turn-off? response to Fe$^{3+}$, which was referred to 1:2 complex formation between ligand (3) and Fe$^{3+}$. The compound was also studied via density functional theory calculations revealing the interaction mechanism of the molecule with Fe$^{3+}$ ions.
A Novel Molecular Imprinting Polymer For The Selective Adsorptionof D-Arabinitol From Spiked Urine, Yuni Retnaningtyas, Ganden Supriyanto, Ni Nyoman Tri Puspaningsih, Roedi Irawan, Siswandono Siswodihardjo
A Novel Molecular Imprinting Polymer For The Selective Adsorptionof D-Arabinitol From Spiked Urine, Yuni Retnaningtyas, Ganden Supriyanto, Ni Nyoman Tri Puspaningsih, Roedi Irawan, Siswandono Siswodihardjo
Turkish Journal of Chemistry
In this research, molecular imprinting polymers (MIPs) for D-arabinitol were synthesized using a bulk polymerization method through a noncovalent approach. The MIPs were prepared by using D-arabinitol as a template, acrylamide as a functional monomer, ethylene glycol dimethacrylateas cross-linker, benzoyl peroxide as an initiator and dimethyl sulfoxideas a porogen. MIPS was synthesized in several formulas with a different molar ratio of template to functional monomers and cross-linker. Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) were used to characterize the MIPs produced. A batch rebinding assay was used to test the binding efficiency of each formula. Batch rebinding test …
L-Proline/Cholesterol And Diosgenin Based Thiourea Cooperative System For The Directasymmetric Aldol Reaction In The Presence Of Water, Serkan Eymur, Eni̇s Taşci, Arzu Uyanik, Mustafa Yilmaz
L-Proline/Cholesterol And Diosgenin Based Thiourea Cooperative System For The Directasymmetric Aldol Reaction In The Presence Of Water, Serkan Eymur, Eni̇s Taşci, Arzu Uyanik, Mustafa Yilmaz
Turkish Journal of Chemistry
A series of cholesterol and based hydrophobic urea and thiourea compounds were synthesized and successfully used as a cocatalyst for L-proline catalyzed aldol reactions in the presence of water. The anticonfigured products were obtained with good yields (up to 94%), high diastereoselectivities (up to 95:5), and high enantiomeric excesses (up to 93% ee). The successful results for catalytic efficiency of L-proline in the presence of water reveal the importance of the hydrophobic nature of cholesterol and diosgenin parts of thiourea on the reactivity and selectivity in the presence of water.
Flowerlike Hybrid Horseradish Peroxidase Nanobiocatalyst For The Polymerization Of Guaiacol, Ersen Göktürk
Flowerlike Hybrid Horseradish Peroxidase Nanobiocatalyst For The Polymerization Of Guaiacol, Ersen Göktürk
Turkish Journal of Chemistry
In this study, the catalytic activity and stability of flowerlike hybrid horseradish peroxidase (HRP) nanobiocatalyst (HRP-Cu$^{2+}$) obtained from Cu$^{2+}$ ions and HRP enzyme in the polymerization reaction of guaiacol were analyzed. We demonstrated that HRP-Cu$^{2+}$ and hydrogen peroxide (H$_{2}$O$_{2}$) initiator showed significantly increased catalytic activity and stability on the polymerization of guaiacol compared to that of free HRP enzyme. Poly(guaiacol) was observed with quite high yields (88%) and molecular weights (38,000 g/mol) under pH 7.4 phosphate-buffered saline (PBS) conditions at 60 °C with 5 weight% of HRP-Cu$^{2+}$ loading. HRP-Cu$^{2+}$ also shows very high thermal stability and works even at 70 …
Determination Of Blood Glucose Parameter From Human Blood Serum By Using A Quartzcrystal Microbalance Sensor Coated With Phthalocyanines Compounds, Evi̇n Şahi̇n Sadik, Hamdi̇ Meli̇h Saraoğlu, İlke Gürol, Mehmet Ali̇ Ebeoğlu, Fatma Emel Koçak
Determination Of Blood Glucose Parameter From Human Blood Serum By Using A Quartzcrystal Microbalance Sensor Coated With Phthalocyanines Compounds, Evi̇n Şahi̇n Sadik, Hamdi̇ Meli̇h Saraoğlu, İlke Gürol, Mehmet Ali̇ Ebeoğlu, Fatma Emel Koçak
Turkish Journal of Chemistry
Determining the blood glucose level is important for the prevention and treatment of diabetes mellitus. We developed a sensor system using Quartz Crystal Microbalance (QCM) to determine the blood glucose level from human blood serum. This study consists of two experimental stages: artificial glucose/pure water solution tests and human blood serum tests. In the first stage of the study, the QCM sensor with the highest performance was identified using artificial glucose solution concentrations. In the second stage of the study, human blood serum measurements were performed using QCM to determine blood glucose levels. QCM sensors were coated with phthalocyanines (Pcs) …
Phase Separation Behavior Of Whey Protein Isolate Particle Dispersions In The Presence Ofxanthan, Alev Emi̇ne İnce Coşkun
Phase Separation Behavior Of Whey Protein Isolate Particle Dispersions In The Presence Ofxanthan, Alev Emi̇ne İnce Coşkun
Turkish Journal of Chemistry
In this study, phase separation of colloidal whey protein isolate (WPI) particle dispersions was studied using a rod-like polysaccharide xanthan. Effects of different xanthan concentration, particle volume fraction, and temperature were analyzed by visual observations, turbidity measurements, and particle mobility tracking method. Particle mobility was determined using a diffusing wave spectroscopy (DWS) set up. Xanthan concentration was kept low in order not to increase the viscosity of dispersions, so that the phase separation could be observed easily. Visual observations showed that there was a minimum concentration of xanthan to induce phase separation at a constant particle volume fraction, and xanthan …
Artificial Intelligence-Based Models For The Qualitative And Quantitative Prediction Of Aphytochemical Compound Using Hplc Method, Abdullahi Garba Usman, Seli̇n Işik, Sani Isah Abba, Fi̇li̇z Meri̇çli̇
Artificial Intelligence-Based Models For The Qualitative And Quantitative Prediction Of Aphytochemical Compound Using Hplc Method, Abdullahi Garba Usman, Seli̇n Işik, Sani Isah Abba, Fi̇li̇z Meri̇çli̇
Turkish Journal of Chemistry
Isoquercitrin is a flavonoid chemical compound that can be extracted from different plant species such as Mangifera indica (mango), Rheum nobile, Annona squamosal, Camellia sinensis (tea), and coriander (Coriandrum sativum L.). It possesses various biological activities such as the prevention of thromboembolism and has anticancer, antiinflammatory, and antifatigue activities. Therefore, there is a critical need to elucidate and predict the qualitative and quantitative properties of this phytochemical compound using the high performance liquid chromatography (HPLC) technique. In this paper, three different nonlinear models including artificial neural network (ANN), adaptive neuro-fuzzy inference system (ANFIS), and support vector machine (SVM),in addition to …
The Production Of Enantiomerically Pure 1-Phenylethanol By Enzymatic Kineticresolution Method Using Response Surface Methodology, Ayşe Bozan, Rahi̇me Songür, Ülkü Mehmetoğlu
The Production Of Enantiomerically Pure 1-Phenylethanol By Enzymatic Kineticresolution Method Using Response Surface Methodology, Ayşe Bozan, Rahi̇me Songür, Ülkü Mehmetoğlu
Turkish Journal of Chemistry
As the enantiomers of 1-phenylethanol are valuable intermediates in several industries, the lipase catalyzed kinetic resolution of (R,S) -1-phenylethanol is a relevant research topic. In this study, the goal was to determine the optimum reaction parameters to produce enantiomerically pure 1-phenylethanol by lipase (Novozyme 435) catalyzed kinetic resolution using response surface methodology (RSM). Reactions were performed with 40-400 mM (R,S)-1-phenylethanol, 120-1200 mM vinyl acetate and 2-22 mg/ mL biocatalyst concentrations (BC$_{L}$), at 20-60 °C and with a stirring rate of 50-400 rpm for 5-120 min. The samples were analyzed using high performance liquid chromatography (HPLC) with a Chiralcel OB column. …
Magnetite Nanoparticles-Based Hydroxyl Radical Scavenging Activity Assay Ofantioxidants Using N, N-Dimethyl-P-Phenylenediamine Probe, Zi̇ya Can, Büşra Keski̇n, Ayşem Arda, Erol Erçağ, Mustafa Reşat Apak
Magnetite Nanoparticles-Based Hydroxyl Radical Scavenging Activity Assay Ofantioxidants Using N, N-Dimethyl-P-Phenylenediamine Probe, Zi̇ya Can, Büşra Keski̇n, Ayşem Arda, Erol Erçağ, Mustafa Reşat Apak
Turkish Journal of Chemistry
Excessive amounts of reactive oxygen species (ROS), unless counterbalanced by antioxidants, can cause cellular damage under oxidative stress conditions; therefore, antioxidative defenses against ROS must be measured. With the development of nanotechnology, nanoparticles have found numerous applications in science, health, and industries. Magnetite nanoparticles (Fe$_{3}$O$_{4}$:MNPs) have attracted attention because of their peroxidase-like activity. In this study, hydroxyl radicals (?OH) generated by MNPs-catalyzed degradation of H$_{2}$O$_{2}$ converted the N,N-dimethyl-p-phenylenediamine (DMPD) probe into its colored DMPD$^{•+}$ radical cation, which gave an absorbance maximum at λ = 553 nm. In the presence of antioxidants, $^{•}$OH was partly scavenged by antioxidants and produced less …
Application Of Synthesized Copper Nanoparticles Using Aqueous Extract Ofziziphus Mauritiana L. Leaves As A Colorimetric Sensor For The Detection Of Ag$^{+}$, Roomia Memon, Ayaz Ali Memon, Syed Tufail Hussain Sherazi, Siraj Uddin, Aamna Balouch, Muhammad Raza Shah, Sarfaraz Ahmed Mahesar, Kauser Rajar, Muhammad Hassan Agheem
Application Of Synthesized Copper Nanoparticles Using Aqueous Extract Ofziziphus Mauritiana L. Leaves As A Colorimetric Sensor For The Detection Of Ag$^{+}$, Roomia Memon, Ayaz Ali Memon, Syed Tufail Hussain Sherazi, Siraj Uddin, Aamna Balouch, Muhammad Raza Shah, Sarfaraz Ahmed Mahesar, Kauser Rajar, Muhammad Hassan Agheem
Turkish Journal of Chemistry
The presented work demonstrates the preparation of copper nanoparticles (CuNPs) via aqueous leaves extract of Ziziphus mauritiana L. (Zm) using hydrazine as a reducing agent. Various parameters such as volume of extract, concentration of hydrazine hydrate, concentration of copper chloride, and pH of the solution were optimized to obtain Ziziphus mauritiana L. leaves extract derived copper nanoparticles (Zm-CuNPs). Brownish red color was initial indication of the formation of Zm-CuNPs while it was confirmed by surface plasmon resonance (SPR) band at wavelength of 584 nm using ultraviolet-visible (UV-vis) spectroscopy. Synthesized Zm-CuNPs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron …
An Efficient Approach For The Synthesis Of Novel Methyl Sulfones In Acetic Acid Mediumand Evaluation Of Antimicrobial Activity, Gollapudi Ravi Kumar, Chandra Rao Dasireddy, Ravi Varala, Vijay Kotra, Hari Babu Bollikolla
An Efficient Approach For The Synthesis Of Novel Methyl Sulfones In Acetic Acid Mediumand Evaluation Of Antimicrobial Activity, Gollapudi Ravi Kumar, Chandra Rao Dasireddy, Ravi Varala, Vijay Kotra, Hari Babu Bollikolla
Turkish Journal of Chemistry
A series of nine methyl sulphones (3a-3i) starting from the aldehydes (1a-1i) were synthesized in two consecutive steps. In the first step, preparation of allyl alcohols (2a-2i) from their corresponding aldehydes by the reaction of sodium borohydride in methanol at room temperature is reported. Finally, methyl sulphones are synthesized by condensing sodium methyl sulfinates with allyl alcohols in the presence of BF$_{3}$.Et$_{2}$O in acetic acid medium at room temperature for about 2-3 h. The reaction conditions are simple, yields are high (85%-95%), and the products were obtained with good purity. All the synthesized compounds were characterized by their $^{1}$H, $^{13}$C …
Synthesis, Characterization And Evaluation Of Antidengue Activity Of Enantiomeric Schiffbases Derived From S-Substituted Dithiocarbazate, Maqsood Maryam, Sang Loon Tan, Karen Ann Crouse, Mohamed Ibrahim Mohamed Tahir, Hui Yee Chee
Synthesis, Characterization And Evaluation Of Antidengue Activity Of Enantiomeric Schiffbases Derived From S-Substituted Dithiocarbazate, Maqsood Maryam, Sang Loon Tan, Karen Ann Crouse, Mohamed Ibrahim Mohamed Tahir, Hui Yee Chee
Turkish Journal of Chemistry
A series of Schiff bases have been successfully synthesized through the acid-catalyzed condensation of S-substituted dithiocarbazates and three enantiomerically pure monoterpenes, (1R)-(+)-camphor, (1S)-(-)-camphor, (1R)-(-)-camphorquinone, (1S)- (+)-camphorquinone, (R)-(-)-carvone and (S)-(+)-carvone. Spectroscopic results revealed that the Schiff bases containing camphor or carvone likely adopted an E-configuration along the characteristic imine bond while those containing camphorquinone assumed a Z-configuration. The antidengue potential of these compounds was evaluated based on DENV 2 caused cytopathic effect (CPE) reduction-based in vitro evaluation. The compounds were validated through secondary foci forming unit reduction assay (FFURA). Compounds were also tested for their cytotoxicity against Vero cells. The compounds …
Design, Synthesis, And Spasmolytic Activity Of Thiophene-Based Derivatives Via Suzukicross-Coupling Reaction Of 5-Bromothiophene-2-Carboxylic Acid: Their Structural Andcomputational Studies, Nasir Rasool, Hafiz Mansoor Ikram, Ammara Rashid, Nazia Afzal, Muhammad Ali Hashmi, Muhammad Naeem Khan, Ayesha Khan, Imran Imran, Hafiz Muhammad Abdur Rahman, Syed Adnan Ali Shah
Design, Synthesis, And Spasmolytic Activity Of Thiophene-Based Derivatives Via Suzukicross-Coupling Reaction Of 5-Bromothiophene-2-Carboxylic Acid: Their Structural Andcomputational Studies, Nasir Rasool, Hafiz Mansoor Ikram, Ammara Rashid, Nazia Afzal, Muhammad Ali Hashmi, Muhammad Naeem Khan, Ayesha Khan, Imran Imran, Hafiz Muhammad Abdur Rahman, Syed Adnan Ali Shah
Turkish Journal of Chemistry
In the current research work, a facile synthesis of a series of novel thiophene-based derivatives of 5-bromothiophene-2- carboxylic acid (1) have been synthesized. All analogs (5a-5e, 10a-10f) were obtained from the coupling reaction of 5-bromothiophene- 2-carboxylic acid (1) and different arylboronic acids with moderate-to-good yields under controlled and optimal conditions. The structures of the newly synthesized compounds were characterized through spectral analysis and their spasmolytic activity, and most of the compounds exhibited potentially good spasmolytic effect. Among the synthesized analogs, compound phenethyl 5-(3,4-dichlorophenyl)thiophene-2-carboxylate (10d) particular showed an excellent spasmolytic effect with an EC$_{50}$ value of 1.26. All of the compounds …
Mathematical Modeling Of A Continuous-Flow Packed-Bed Reactor With Immobilizedlipase For Kinetic Resolution Of (R,S)-2-Pentanol, Asli Soyer Malyemez, Abdulwahap Giwa, Emi̇ne Bayraktar, Ülkü Mehmetoğlu
Mathematical Modeling Of A Continuous-Flow Packed-Bed Reactor With Immobilizedlipase For Kinetic Resolution Of (R,S)-2-Pentanol, Asli Soyer Malyemez, Abdulwahap Giwa, Emi̇ne Bayraktar, Ülkü Mehmetoğlu
Turkish Journal of Chemistry
In this study, the kinetic resolution of (R,S)-2-pentanol via transesterification to achieve S-2-pentanol, a key intermediate required in the synthesis of anti-Alzheimer drugs, was investigated in continuous-flow packed-bed reactors. The effects of residence time, substrate concentration, and operation time of the enzyme were investigated. Under steady state conditions, 50% conversion and enantiomeric excess of the substrate (ee$_{S}$)>99% were achieved at a residence time of 0.04 min. Productivity of the continuous-flow process (1.341 mmol/min/g)was about 4 times higher than that of the corresponding batch process (0.363 mmol/min/g). In addition, the mathematical modeling of the packed-bed reactor was conductedusing an axial …