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Full-Text Articles in Physical Sciences and Mathematics

Evaluation Of Carbonic Anhydrase And Paraoxonase Inhibition Activities And Molecular Docking Studies Of Highly Water-Soluble Sulfonated Phthalocyanines, Emre Güzel, Fati̇h Sönmez, Sultan Erkan, Kübra Çikrikci, Adem Ergün, Nahi̇t Gençer, Oktay Arslan, Makbule Koçak Jan 2020

Evaluation Of Carbonic Anhydrase And Paraoxonase Inhibition Activities And Molecular Docking Studies Of Highly Water-Soluble Sulfonated Phthalocyanines, Emre Güzel, Fati̇h Sönmez, Sultan Erkan, Kübra Çikrikci, Adem Ergün, Nahi̇t Gençer, Oktay Arslan, Makbule Koçak

Turkish Journal of Chemistry

The investigation of carbonic anhydrase and paraoxonase enzyme inhibition properties of water-soluble zinc and gallium phthalocyanine complexes (1 and 2) are reported for the first time. The binding of p-sulfonylphenoxy moieties to the phthalocyanine structure favors excellent solubilities in water, as well as providing an inhibition effect on carbonic anhydrase (CA) I and II isoenzymes and paraoxonase (PON1) enzyme. According to biological activity results, both complexes inhibited hCA I, hCA II, and PON1. Whereas 1 and 2 showed moderate hCA I and hCA II (off-target cytosolic isoforms) inhibitory activity (Ki values of 26.09 μM and 43.11 μM for hCA I …


Computational And Biological Studies Of Novel Thiazolyl Coumarin Derivatives Synthesized Through Suzuki Coupling, Shaista Parveen, Saima Kalsoom, Rifhat Bibi, Ambreen Asghar, Abdul Hameed, Waqar Ahmed, Abbas Hassan Jan 2020

Computational And Biological Studies Of Novel Thiazolyl Coumarin Derivatives Synthesized Through Suzuki Coupling, Shaista Parveen, Saima Kalsoom, Rifhat Bibi, Ambreen Asghar, Abdul Hameed, Waqar Ahmed, Abbas Hassan

Turkish Journal of Chemistry

The current investigation presents the synthesis, computational molecular-docking and biological activity studies of arylated thiazole coumarins. Aryl substituted thiazolyl coumarin derivatives were synthesized via Suzuki cross-coupling reaction. A detailed reaction condition optimization revealed that the Pd-PEPPSI-IPent precatalyst in only 2 mol% loading resulted in the desired product with high yield. The aim of this study was to examine the antimicrobial behavior of thiazole coumarin derivatives through in vitro and in silico studies. All the compounds showed activity against both antibacterial strains, Staphylococcus aureus and Escherichia coli, except 5d. Similarly, the compounds 5a, 5b, and 5d were found to be active …


Synthesis And Molecular Docking Studies Of Quinoline Derivatives As Hiv Non-Nucleoside Reverse Transcriptase Inhibitors, Nivedita Bhardwaj, Diksha Choudhary, Akashdeep Pathania, Somesh Baranwal, Pradeep Kumar Jan 2020

Synthesis And Molecular Docking Studies Of Quinoline Derivatives As Hiv Non-Nucleoside Reverse Transcriptase Inhibitors, Nivedita Bhardwaj, Diksha Choudhary, Akashdeep Pathania, Somesh Baranwal, Pradeep Kumar

Turkish Journal of Chemistry

Quinoline moiety is an important scaffold in the field of drug discovery and drug development, with a wide range of pharmacological activities. Quinoline derivatives are potent inhibitors for reverse transcriptase, which is responsible for the conversion of single-stranded viral RNA into double-stranded viral DNA.In the present study, we have designed and synthesized 2 series, namely pyrazoline and pyrimidine containing quinoline derivatives as non nucleoside reverse transcriptase inhibitors (NNRTIs). Eleven compounds were synthesized and characterized by 1H and 13C NMR and mass spectrophotometry. The synthesized compounds were also docked on an HIV reverse transcriptase binding site (PDB: 4I2P); most of these …


Blue Tio2 Nanotube Arrays As Semimetallic Materials With Enhanced Photoelectrochemical Activity Towards Water Splitting, Naeimeh Sadat Peighambardoust, Umut Aydemir Jan 2020

Blue Tio2 Nanotube Arrays As Semimetallic Materials With Enhanced Photoelectrochemical Activity Towards Water Splitting, Naeimeh Sadat Peighambardoust, Umut Aydemir

Turkish Journal of Chemistry

In the past years there has been a great interest in self-doped TiO2 nanotubes (blue TiO2 nanotubes) compared to undoped ones owing to their high carrier density and conductivity. In this study, blue TiO2 nanotubes are investigated as photoanode materials for photoelectrochemical water splitting. Blue TiO2 nanotubes were fabricated with enhanced photoresponse behavior through electrochemical cathodic polarization on undoped and annealed TiO2 nanotubes. The annealing temperature of undoped TiO2 nanotubes was tuned before cathodic polarization, revealing that annealing at 500 °C improved the photoresponse of the nanotubes significantly. Further optimization of the blue TiO2 nanotubes was achieved by adjusting the …


Comparison Of Antioxidant Capacities And Antioxidant Components Of Commercial Bitter Melon (Momordica Charantia L.) Products, Esi̇n Akyüz, Sercan Türkoğlu, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak Jan 2020

Comparison Of Antioxidant Capacities And Antioxidant Components Of Commercial Bitter Melon (Momordica Charantia L.) Products, Esi̇n Akyüz, Sercan Türkoğlu, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak

Turkish Journal of Chemistry

In this study, the total phenolic contents and total antioxidant capacities of some commercial bitter melon products (powder, packaged powder, capsule, paste in olive oil), and of unripe and ripe fruits were determined by spectrophotometric and chromatographic methods. The total antioxidant capacities of unripe and ripe bitter melon samples, determined by using the CUPRAC (cupric reducing antioxidant capacity assay) and ABTS (2,2'-Azinobis-(3-Ethylbenzthiazolin-6-Sulfonic Acid)/HRP (horseradish peroxidase) methods, were 42.5 and 36.3 μmol TRE (Trolox equivalent) g-1, and 8.7 and 7.0 μmol TRE g-1, respectively. The TAC (total antioxidant capacity) order of the studied samples using the same 2 methods were determined …


Structural Insights Of Two Novel N-Acetyl-Glucosaminidase Enzymes Through In Silico Methods, Ari̇f Sercan Şahutoğlu, Hati̇ce Duman, Steven Alex Frese, Sercan Karav Jan 2020

Structural Insights Of Two Novel N-Acetyl-Glucosaminidase Enzymes Through In Silico Methods, Ari̇f Sercan Şahutoğlu, Hati̇ce Duman, Steven Alex Frese, Sercan Karav

Turkish Journal of Chemistry

EndoBI-1 and EndoBI-2 are two endo-β-N-acetylglucosaminidase isoenzymes that cleave N-N'-diacetylchitobiosyl moieties found in various types of native N-glycans. These N-glycans are indigestible by human infants and adults due to the lack of responsible glycosyl hydrolases and they act as selective prebiotics for a probiotic microorganism, Bifidobacterium longum subsp. infantis, in the large intestine. The selectivity and the thermostability of EndoBI-1 and EndoBI-2 suggest that these enzymes may be useful for many scientific and industrial applications. In this study, the growing numbers of homologous sequences in different databases were exploited in a comparative approach to investigate structural properties of EndoBI-1 and …


Highly Luminescent Water-Dispersed Silicon Quantum Dots For Fluorometric Determination Of Oxytetracycline In Milk Samples, Hayri̇ye Eda Şatana Kara, Burak Demi̇rhan, Buket Er Demi̇rhan Jan 2020

Highly Luminescent Water-Dispersed Silicon Quantum Dots For Fluorometric Determination Of Oxytetracycline In Milk Samples, Hayri̇ye Eda Şatana Kara, Burak Demi̇rhan, Buket Er Demi̇rhan

Turkish Journal of Chemistry

A fluorescent probe based on silicon quantum dots (SiQDs) was developed for the selective and sensitive detection of oxytetracycline (OTC) via the inner filter effect (IFE). The water-soluble fluorescent SiQD was synthesized based on the reaction of 3-Aminopropyltriethoxysilane (APTES) and sodium citrate as precursors by the one-pot hydrothermal process. The strong fluorescence emission of quantum dots (QDs) was obtained at 440 nm when excited at 350 nm and OTC had a broad absorption band between 200 and 400 nm. The excitation spectrum of SiQDs was completely overlapped with the absorption spectrum of OTC. The light at an excitation wavelength of …


Fabrication And Characterization Of Boric Acid-Crosslinked Ethyl Cellulose And Polyvinyl Alcohol Films As Potential Drug Release Systems For Topical Drug Delivery, Nasrin Aliasgharlou, Farzin Asghari Sana, Saba Khoshbakht, Pezhman Zolfaghari, Hamed Charkhian Jan 2020

Fabrication And Characterization Of Boric Acid-Crosslinked Ethyl Cellulose And Polyvinyl Alcohol Films As Potential Drug Release Systems For Topical Drug Delivery, Nasrin Aliasgharlou, Farzin Asghari Sana, Saba Khoshbakht, Pezhman Zolfaghari, Hamed Charkhian

Turkish Journal of Chemistry

In this study, boric acid (BA) is employed as a crosslinking agent to improve the characteristics of two commonly used polymeric films, ethyl cellulose (EC) and polyvinyl alcohol (PVA), for topical drug delivery applications. The developed films are characterized by FTIR spectroscopy and SEM analysis. The results show that the surfaces of the prepared films are even and transparent, except for the BA-modified EC sample. The initial cumulative release for erythromycin (EM) is found to be 0.30 and 0.36 mg/mL for EC and PVA films, which drops to 0.25 and 0.20 mg/mL after BA crosslinking, respectively, after 1 h at …


Synthesis, Antioxidant And Antimicrobial Properties Of Novel Pyridyl-Carbonyl Thiazoles As Dendrodoine Analogs, Zafer Şahi̇n, Sevde Nur Bi̇lteki̇n, Leyla Yurttaş, Şeref Demi̇rayak Jan 2020

Synthesis, Antioxidant And Antimicrobial Properties Of Novel Pyridyl-Carbonyl Thiazoles As Dendrodoine Analogs, Zafer Şahi̇n, Sevde Nur Bi̇lteki̇n, Leyla Yurttaş, Şeref Demi̇rayak

Turkish Journal of Chemistry

Marine compound dendrodoine was first obtained from tunicate species (Dendrodo grossularia). It has a five-membered ring, namely, it is a heterocycle thiadiazole, which is found rarely in natural sources. Following its biological activities, novel analogs have been investigated recently. Synthesis of the analogs for this study is realized with uncommon thiazole closure, including methylene-carbonyl condensation. Structures are elucidated by NMR (1H, 13C) and HRMS spectrums. As an alkaloid derivative, antioxidant properties were evaluated with DPPH and FRAP assays and antimicrobial effect with microdilution method. Among the series, 3bc-3cf showed higher antioxidant activity than those having 3 or 4-pyridyl substituents. There …


An Insight Into The Therapeutic Potential Of Piperazine-Based Anticancer Agents, Kamran Walayat, Noor Ul Amin Mohsin, Sana Aslam, Matloob Ahmad Jan 2019

An Insight Into The Therapeutic Potential Of Piperazine-Based Anticancer Agents, Kamran Walayat, Noor Ul Amin Mohsin, Sana Aslam, Matloob Ahmad

Turkish Journal of Chemistry

The piperazine ring system is among the medicinally important nitrogen-containing heterocyclic ring systems and is exploited for the synthesis of various drug molecules. A number of FDA-approved anticancer drugs contain piperazine rings and thus it is considered as an attractive scaffold having extraordinary potential for the development of new anticancer agents. In recent decades there has been an alarming increase in the number of people suffering from cancerous diseases all over the world, which resulted in an extraordinary increase in research reports on new anticancer drug candidates. The aim of this article is to highlight the structural parameters imparting anticancer …


Why Protein Conformers In Molecular Dynamics Simulations Differ From Their Crystal Structures: A Thermodynamic Insight, Fi̇li̇ppo Pullara, Mao Wenzhi, Mert Gür Jan 2019

Why Protein Conformers In Molecular Dynamics Simulations Differ From Their Crystal Structures: A Thermodynamic Insight, Fi̇li̇ppo Pullara, Mao Wenzhi, Mert Gür

Turkish Journal of Chemistry

Conformers generally deviate structurally from their starting X-ray crystal structures early in molecular dynamics (MD) simulations. Studies have recognized such structural differences and attempted to provide an explanation for and justify the necessity of MD equilibrations. However, a detailed explanation based on fundamental physics and validation on a large ensemble of protein structures is still missing. Here we provide the first thermodynamic insights into the radically different thermodynamic conditions of crystallization solutions and conventional MD simulations. Crystallization solution conditions can lead to nonphysiologically high ion concentrations, low temperatures, and crystal packing with strong specific protein--protein interactions, not present under physiological …


Comparative Study On Physicochemical And Mechanical Characterization Of New Nanocarbon-Based Hydroxyapatite Nanocomposites, Reka Barabas, Dennis Deemter, Gabriel Katona, Gabriel Batin, Laszlo Barabas, Liliana Bizo, Oana Cadar Jan 2019

Comparative Study On Physicochemical And Mechanical Characterization Of New Nanocarbon-Based Hydroxyapatite Nanocomposites, Reka Barabas, Dennis Deemter, Gabriel Katona, Gabriel Batin, Laszlo Barabas, Liliana Bizo, Oana Cadar

Turkish Journal of Chemistry

This study evaluated the effect of different additives such as nanocarbon compounds (0.5, 1.0, and 2.0 wt.%) with different morphologies and gelatin (Gel) (10 wt.%) on the mechanical properties of hydroxyapatite (Hap)-based nanocomposites (NCs). The NCs were prepared using the innovation process "SmartBox" based on the Internet of things (IoT), which provides process control and reproducibility, and they were characterized by X-ray diffraction, particle size distribution, transmission electron microscopy, Fourier transform infrared spectroscopy, and thermal analysis. The compressive strength tests demonstrated that the use of grapheme oxide (Hap_ GO_ 2.0 - 133 N/mm$^{2})$, and/or Gel (Hap_ Gel - 152 N/mm$^{2})$ …


Synthesis And Characterization Of Polycaprolactone-Based Segmented Polyurethanes, Aysun Güney, Aysel Kiziltay, Nesri̇n Hasirci, Tuğba Endoğan Tanir Jan 2019

Synthesis And Characterization Of Polycaprolactone-Based Segmented Polyurethanes, Aysun Güney, Aysel Kiziltay, Nesri̇n Hasirci, Tuğba Endoğan Tanir

Turkish Journal of Chemistry

Segmented polyurethanes were synthesized by the reactions of poly($\varepsilon $-caprolactone) (PCL)-diol and 1,6-hexamethylene diisocyanate through bulk polymerization without using solvent, initiator, or catalyst. Phase separation and hydrogen bond formation between hard segments or between hard and soft segments were examined by Fourier transform infrared spectroscopy (FTIR)-ATR and X-ray diffraction (XRD), while physical and mechanical properties were studied by atomic force microscope, differential scanning calorimeter, dynamic mechanical analysis, and tensile tester. When the diisocyanate content was increased, deconvolution results of FTIR-ATR in C$=$O and N-H regions demonstrated better miscibility of the segments and XRD results showed a significant decrease in the …


Electrodeposition Of Tin(Ii) From Citrate Complexes, Yuliya Yapontseva, Valeriy Kublanovsky Jan 2019

Electrodeposition Of Tin(Ii) From Citrate Complexes, Yuliya Yapontseva, Valeriy Kublanovsky

Turkish Journal of Chemistry

This paper provides the calculation of the distribution of the concentrations of complex particles of the Sn(II) - citrate - water system in the solution volume, on the surface of the electrode, and in the diffusion layer for the tin citrate electrolyte containing an excess of the ligand. Based on the calculations for the electrodeposition of tin, an electrolyte containing [SnCit]$^{2-}$ complex at pH 8.0 was chosen. The kinetic parameters of the discharge stage, the diffusion coefficient of the electrochemical active ion, and the current efficiency of tin were determined by the methods of stationary voltammetry and chronovoltamperometry. It is …


Improvement Of The Mechanical And Thermal Properties Of Polyester Nonwoven Fabrics By Ptfe Coating, Fatemeh Ashrafi, Mohammad Reza Babaei Lavasani Jan 2019

Improvement Of The Mechanical And Thermal Properties Of Polyester Nonwoven Fabrics By Ptfe Coating, Fatemeh Ashrafi, Mohammad Reza Babaei Lavasani

Turkish Journal of Chemistry

Polyester (polyethylene terephthalate) is one of the most widely used polymers in textiles. Despite all the advantages of this polymer, its low thermal resistance limits its use in filters and protective textiles. On the other hand, polyester nonwovens are used in many products as wipes, filters, and padding. The surface properties of polyester nonwovens are often not perfect for a specific application and need to be modified. Different ways, including coating, have been developed to modify their surface properties. Therefore, in the present study attempts were made to investigate the improvement of the thermal resistance of a polyester nonwoven by …


Synthesis Of Smz Derivatives And Investigation Of Effects On Germination, Root, And Plant Growth Of \Textit{Arabidopsis Thaliana} L., Tuğba Güngör, Ferah Cömert Önder, Fati̇h Sezer, Aslihan Özbi̇len, Kemal Meli̇h Taşkin, Mehmet Ay Jan 2019

Synthesis Of Smz Derivatives And Investigation Of Effects On Germination, Root, And Plant Growth Of \Textit{Arabidopsis Thaliana} L., Tuğba Güngör, Ferah Cömert Önder, Fati̇h Sezer, Aslihan Özbi̇len, Kemal Meli̇h Taşkin, Mehmet Ay

Turkish Journal of Chemistry

A series of sulfonamide derivatives were synthesized by reactions with various functional groups containing benzenesulfonyl chlorides and aniline derivatives under different substitution reaction conditions. The structures of SMZ derivatives were confirmed with melting point, FT-IR, $^{1}$H NMR, $^{13}$C NMR, and LC-MS/MS techniques. In order to investigate the cytotoxic effects of these derivatives, we used a model plant species. The synthesized compounds (S1-S5) and sulfamethazine (SMZ) as a positive control were applied to Arabidopsis thaliana seeds. Our results indicated that S3 and S4 induced shorter roots and lower wet weight in plants. Plants treated with S2 and S5 showed no growth …


Synthesis And Bioactivity Of Sulfide Derivatives Containing 1,3,4-Oxadiazole And Pyridine, Gang Yu, Shunhong Chen, Feng He, Dexia Luo, Yu Zhang, Jian Wu Jan 2019

Synthesis And Bioactivity Of Sulfide Derivatives Containing 1,3,4-Oxadiazole And Pyridine, Gang Yu, Shunhong Chen, Feng He, Dexia Luo, Yu Zhang, Jian Wu

Turkish Journal of Chemistry

A series of novel sulfide derivatives containing 1,3,4-oxadiazole and pyridine were synthesized, characterized, and tested for their antibacterial activity against tobacco bacterial wilt and rice bacterial blight and for insecticidal activity toward diamondback moth. The results showed that some compounds had good insecticidal and bactericidal activity, e.g., the activities of compounds 6e and 6g-6j toward tobacco bacterial wilt were much better than those of commercial thiodiazole-copper, and some of the synthesized compounds possessed good insecticidal activity against Plutella xylostella. Compounds 6d, 6h, 6j, 6l, 6p, 6r, and 6p displayed over 93% activity at 500 mg L$^{-1}$.


Acetyl- And Butyrylcholinesterase Inhibitory Activity Of Selected Photochemically Synthesized Polycycles, Ivana Sagud, Irena Skoric, Dragana Vuk, Ana Ratkovic, Franko Burcul Jan 2019

Acetyl- And Butyrylcholinesterase Inhibitory Activity Of Selected Photochemically Synthesized Polycycles, Ivana Sagud, Irena Skoric, Dragana Vuk, Ana Ratkovic, Franko Burcul

Turkish Journal of Chemistry

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the main cause of dementia in the elderly population. Since the treatment of AD has been associated with the activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), their inhibitors remain the main focus of AD investigations. In this study we evaluated cholinesterase inhibitory activity of 14 bicyclo[3.2.1]octene/octadiene derivatives and naturally occurring sesquiterpene alcohol cedrol. These 14 compounds have been efficiently and ecologically prepared by a photochemical approach in batch photochemical reactors. Various compounds with the bicyclo[3.2.1]octene skeleton have already been successfully evaluated for treatment of central nervous system disorders and AD. Among …


A Novel Silver(I)-Selective Pvc Membrane Sensor And Its Potentiometric Applications, Ömer Işildak, Ni̇hal Deli̇gönül, Oğuz Özbek Jan 2019

A Novel Silver(I)-Selective Pvc Membrane Sensor And Its Potentiometric Applications, Ömer Işildak, Ni̇hal Deli̇gönül, Oğuz Özbek

Turkish Journal of Chemistry

Silver(I)-selective sensors were prepared from a solid-state contact polyvinyl chloride (PVC) membrane. ($Z)$-2-(2-((3-(2-hydroxyphenyl)-5-(p-tolyl)-1$H$-pyrrol-2-yl)imino)-5-(p-tolyl)-2$H$-pyrrol-3-yl)phenol was synthesized as an ionophore molecule and embedded in the silver(I)-selective PVC membrane composition. The optimum membrane composition was determined as 2.5% ionophore, 61.7% bis-(2-ethylhexyl)sebacate, 1.0% potassium tetrakis (p-chlorophenyl) borate, and 34.8% PVC. The developed sensor exhibited a linear potential change $E$ = 67.42 (-log [Ag$^{+}$]) $+$ 1152.9 and $R^{2}$ = 0.9960) in the varying concentration range of 1.0 $\times $ 10$^{-1}$ to 1.0 $\times $ 10$^{-5}$ mol L$^{-1}$ silver ions. This sensor shows a detection limit of 7.3 $\times $ 10$^{-7}$ mol L$^{-1}$. The proposed sensor …


Mwcnts-Fe$_{2}$O$_{3}$ Nanoparticle Nanohybrid-Based Highly Sensitive Electrochemical Sensor For The Detection Of Kaempferol In Broccoli Samples, Nomnotho Jiyane, Myalowenkosi I. Sabela, Suvardhan Kanchi, Phumlane S. Mdluli, Mavis Xhakaza, Olayide A. Arodola, Krishna Bisetty Jan 2019

Mwcnts-Fe$_{2}$O$_{3}$ Nanoparticle Nanohybrid-Based Highly Sensitive Electrochemical Sensor For The Detection Of Kaempferol In Broccoli Samples, Nomnotho Jiyane, Myalowenkosi I. Sabela, Suvardhan Kanchi, Phumlane S. Mdluli, Mavis Xhakaza, Olayide A. Arodola, Krishna Bisetty

Turkish Journal of Chemistry

This work reports an electrochemical sensor with a modified glassy carbon electrode for the detection of kaempferol. The method was tailored by the immobilization of multiwalled carbon nanotubes (MWCNTs) assimilated with Fe$_{2}$O$_{3}$ nanoparticles (NPs) onto the electrode surface to detect kaempferol using differential pulse voltammetry. Thermogravimetric, transmission electron microscopic, cyclic, and differential voltammetric techniques were employed to characterize the developed electrochemical sensor. The kaempferol produces an anodic quasireversible peak at pH 6.6 in phosphate buffer with Fe$_{2}$O$_{3}$NPs/MWCNTs/GCE. The current of the anodic peak at 0.32 V increases linearly upon addition of kaempferol standard, resulting in Ip($\mu $A) = 1.577($\mu $M) …


Silylation Of Epoxidized Soybean Oil With Triethoxysilanes, Synthesis And Characterization Of Their Polyurethanes, Aynur Özşeker, Kemal Karadeni̇z, Mustafa Yasi̇n Şen Jan 2019

Silylation Of Epoxidized Soybean Oil With Triethoxysilanes, Synthesis And Characterization Of Their Polyurethanes, Aynur Özşeker, Kemal Karadeni̇z, Mustafa Yasi̇n Şen

Turkish Journal of Chemistry

Silylation of epoxidized soybean oil (ESBO) was carried out by epoxy ring opening reaction of methoxy and ethoxy silane compounds. $^{1}$H NMR and FTIR spectra confirmed that two novel bio-based polyols, PSiTh and PSiAm, were obtained through the ring opening of epoxy by the mercapto and amino moieties of MPTMS and APTES, respectively. Polyurethanes of these polyols were prepared using 4,4'- methylene-bis(phenyl isocyanate) (MDI) to incorporate silanol groups into polymer network and were labeled as PUSiTh and PUSiAm, respectively. To see the impact of silanol and phosphorous groups on flame retardant properties, the chain extended polyurethanes, PUSiThCE and PUSiAmCE were …


Ionic Liquid-Based Graphene Oxide-Coated Fiber For Headspace-Solid Phase Microextraction Of Polycyclic Aromatic Hydrocarbons In Water Samples, Peli̇n Erdem, Paniz Tashakkori, Melek Merdi̇van, Serap Seyhan Bozkurt Jan 2019

Ionic Liquid-Based Graphene Oxide-Coated Fiber For Headspace-Solid Phase Microextraction Of Polycyclic Aromatic Hydrocarbons In Water Samples, Peli̇n Erdem, Paniz Tashakkori, Melek Merdi̇van, Serap Seyhan Bozkurt

Turkish Journal of Chemistry

Ionic liquid (IL) containing amino and vinyl terminated imidazolium cation and bis[(trifluoromethyl)sulfonyl] imide anion-functionalized graphene oxide (GO) coating material was prepared and coated on a stainless steel wire by a sol-gel technique for headspace-solid phase microextraction (HS-SPME). Its extraction performance was checked by HS-SPME of polycyclic aromatic hydrocarbons (PAHs) coupled to gas chromatography with mass spectrometry (GC-MS). The extraction capability of the IL-functionalized GO-coated fiber was comparable with that of the commercial fibers of polydimethylsiloxane (PDMS) and polydimethylsiloxane/carboxen/divinylbenzene (PDMS/CAR/DVB). Under the optimized conditions, such as extraction temperature, extraction time, and salting-out, the proposed HS-SPME-GC-MS method presented a wide working range …


Ann-Assisted Forecasting Of Adsorption Efficiency To Remove Heavy Metals, Magdi Buaisha, Şazi̇ye Balku, Şeni̇z Özalp Yaman Jan 2019

Ann-Assisted Forecasting Of Adsorption Efficiency To Remove Heavy Metals, Magdi Buaisha, Şazi̇ye Balku, Şeni̇z Özalp Yaman

Turkish Journal of Chemistry

In wastewater treatment, scientific and practical models utilizing numerical computational techniques such as artificial neural networks (ANNs) can significantly help to improve the process as a whole through adsorption systems. In the modeling of the adsorption efficiency for heavy metals from wastewater, some kinetic models have been used such as pseudo first-order and second-order. The present work develops an ANN model to forecast the adsorption efficiency of heavy metals such as zinc, nickel, and copper by extracting experimental data from three case studies. To do this, we apply trial-and-error to find the most ideal ANN settings, the efficiency of which …


Synthesis And Characterization Of Novel Indanone-Based Spiro-Dihydrobenzofuran Derivatives, Meli̇ha Burcu Gürdere, Neşe Dürü, Yakup Budak, Mustafa Ceylan Jan 2019

Synthesis And Characterization Of Novel Indanone-Based Spiro-Dihydrobenzofuran Derivatives, Meli̇ha Burcu Gürdere, Neşe Dürü, Yakup Budak, Mustafa Ceylan

Turkish Journal of Chemistry

In this study, the synthesis and characterization of novel indanone-based spiro-dihydrobenzofuran derivatives were examined. Firstly, chalcone-like compounds 4a-k, ($E)$-2-benzylidene-2,3-dihydro-1$H$-inden-1-one derivatives, were synthesized by the base-catalyzed addition of benzaldehyde derivatives to 2,3-dihydro-1$H$-inden-1-one. Then Mn(OAc)$_{3}$-mediated addition of dimedone (2) to the chalcone-like compounds gave two novel spiro-dihydrobenzofuran isomers: (3$S)$-6,6-dimethyl-3-aryl-6,7-dihydro-3$H$-spiro [benzofuran-2,2'-indene]-1',4(3'$H$,5$H)$-dione (5a-k) and (2'$S)$-6,6-dimethyl-2-aryl-6,7-dihydro-2$H$-spiro[benzofuran-3,2'-indene]-1',4(3'$H$,5$H)$-dione (6a-k) in good yields. The isomers were separated by column chromatography and their structures were elucidated on the basis of spectral data (NMR, IR) and elemental analysis.


Synthesis And Characterization Of Novel Mussel-Inspired Benzoxazines By Thiol-Benzoxazine Chemistry, Mustafa Arslan Jan 2019

Synthesis And Characterization Of Novel Mussel-Inspired Benzoxazines By Thiol-Benzoxazine Chemistry, Mustafa Arslan

Turkish Journal of Chemistry

A catechol-based benzoxazine copolymer is reported via a new approach using an oxazine-thiol reaction. The main chain benzoxazine precursor was obtained via the classic benzoxazine synthesis methodology using the raw chemicals catechol, formaldehyde, and 4,7,10-trioxa-1,13-tridecanediamine. The countercomponent was synthesized from poly(ethylene glycol) methyl ether via the Fischer esterification reaction. The obtained reactive catechol-based benzoxazine was then reacted in mild conditions with polymeric thiol precursor to obtain a copolymer structure. The precursors and the resulting structure were characterized by thermal and spectral analyses using DSC, TGA, FT-IR,$^{\, 1}$H NMR, and GPC. Film formation was also demonstrated with unreacted oxazine ring units …


Step-By-Step Optimization Of The Hilic Method For Simultaneous Determination Of Abacavir, Lamivudine, And Zidovudine From Dosage Form, Cem Erkmen, Mehmet Gümüştaş, Si̇bel Ayşil Özkan, Bengi̇ Uslu Jan 2019

Step-By-Step Optimization Of The Hilic Method For Simultaneous Determination Of Abacavir, Lamivudine, And Zidovudine From Dosage Form, Cem Erkmen, Mehmet Gümüştaş, Si̇bel Ayşil Özkan, Bengi̇ Uslu

Turkish Journal of Chemistry

Combined therapy for HIV treatment shows superior efficacy in comparison to single therapy. Furthermore, the separation and determination of the combined dosage forms hold a significant place in the pharmaceutical industry. Not only reverse phase high-performance liquid chromatography (HPLC) but also hydrophilic interaction liquid chromatography (HILIC) can be used for these purposes. Contrary to conventional RP systems, HILIC may be an alternative for the analysis of polar substances. The aim of this study was the step-by-step development of a simple, rapid, and reliable method for the simultaneous determination of antiviral compounds from their marketed formulation (Trizivir). In order to achieve …


Synthesis Of Hofmann-Type Zn(H$_2$O)$_2$Ni(Cn)$_4$.Ng (G = Water And 1,4-Dioxane) Clathrates And The Determination Of Their Structural Properties By Various Spectroscopic Methods, Zeki̇ Kartal, Onur Şahi̇n, Abdülkeri̇m Yavuz Jan 2019

Synthesis Of Hofmann-Type Zn(H$_2$O)$_2$Ni(Cn)$_4$.Ng (G = Water And 1,4-Dioxane) Clathrates And The Determination Of Their Structural Properties By Various Spectroscopic Methods, Zeki̇ Kartal, Onur Şahi̇n, Abdülkeri̇m Yavuz

Turkish Journal of Chemistry

Two new 2-dimensional cyanide-bridged coordination polymers [Zn(H$_{2}$O)$_{2}$Ni(CN)$_{4}$ 6(H$_{2}$O) and Zn(H$_{2}$O)$_{2}$ Ni(CN)$_{4}$ 3(C$_{4}$H$_{8}$O$_{2})$], which were similar to Hofmann-type clathrates, were synthesized based on [Ni(CN)$_{4}$]$^{2-}$ and Zn$^{2+}$ as building blocks. These substances were synthesized as compounds in crystalline form. Thes tructures of the crystalline compounds were characterized via their spectral analyses. General information about the structures of the newly obtained Hofmann-type clathrates was obtained from their vibration spectra by considering significant changes in the vibration peaks of the cyanide group, water ligand molecule, and guest molecules (water and 1,4-dioxane). The thermal behavior of the Hofmann-type clathrates was investigated in the range of …


Surface Modification Of Polyvinyl Chloride By Polyacrylic Acid Graftas A Polyelectrolyte Membrane Using Ar Plasma, Alaa Fahmy, Mouhamed Abu-Saied, Nasser Morgan, Walid Qutop, Hassan Abdelbary, Tarek Salama Jan 2019

Surface Modification Of Polyvinyl Chloride By Polyacrylic Acid Graftas A Polyelectrolyte Membrane Using Ar Plasma, Alaa Fahmy, Mouhamed Abu-Saied, Nasser Morgan, Walid Qutop, Hassan Abdelbary, Tarek Salama

Turkish Journal of Chemistry

This work reports the synthesis and properties of a new membrane based on polyvinyl chloride (PVC) grafting with polyacrylic acid (PAA) using argon (Ar) plasma. The membranes of PVC were synthesized by solution-casting method, where PAA was deposited as an ultrathin film onto PVC using dielectric barrier discharge at atmospheric pressure with Ar gas. The surface characteristics and chemical composition of the modified membranes were analyzed by water contact angle, scanning electron microscopy, and Fourier transform infrared spectroscopy. Moreover, the electrochemical properties of the membrane were investigated via ion exchange capacity for the purpose of using it as a polyelectrolyte …


Synthesis And Antitumor Activities Of 2-(Piperidin-4-Yl)-Thiazole-4-Carboxamides Analogues Of Tubulysins, Xiangfu Peng, Mingsha Shao, Shuchao Ma, Lei Yao Jan 2019

Synthesis And Antitumor Activities Of 2-(Piperidin-4-Yl)-Thiazole-4-Carboxamides Analogues Of Tubulysins, Xiangfu Peng, Mingsha Shao, Shuchao Ma, Lei Yao

Turkish Journal of Chemistry

}Tubulysins are a family of natural products that exhibit potent antitumor activities, which have attracted much attention from synthetic and medicinal chemists. Previous attempts to aromatize the Tuv part of tubulysin analogues led to a loss in antitumor activity, which suggested that the Ile and Tuv fragments of these analogues were adopting different conformations than the natural products. In this study, a series of 2-(piperidin-4-yl)-thiazole-4-carboxamides have been prepared to investigate whether an intramolecular H-bond between key NH and OH groups is responsible for the conformational control. The antitumor activities of these analogues have been screened using MDA-MB-231-breast, Siha-cervical, MCF7-breast, and …


A Fast And Convenient Analysis Method For The Determination Of Cations In Pomegranate Juices By Capillary Electrophoresis With Contactless Conductivity Detection, Veseli̇na Adimcilar, Nevi̇n Özteki̇n Jan 2019

A Fast And Convenient Analysis Method For The Determination Of Cations In Pomegranate Juices By Capillary Electrophoresis With Contactless Conductivity Detection, Veseli̇na Adimcilar, Nevi̇n Özteki̇n

Turkish Journal of Chemistry

Health beneficial effect of pomegranate is mainly due to its confirmed high antioxidant capacity and polyphenolic content. In recent years, experimental and clinical studies have shown that pomegranate intake lowers blood pressure. Potassium and other minerals such as calcium and magnesium may be responsible for this property. In this study, a rapid, economic, reliable, and applicable capillary electrophoresis method was proposed with contactless conductivity detection for the quantitative determination of six cations in different pomegranate juices. The correlation between these cation contents of eight different pomegranate juices was evaluated by using one-way ANOVA and Duncan's multiple-range test. The optimum buffer …