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Operator Index Of A Nonsingular Algebraic Curve, Anar Dosi̇ Nov 2023

Operator Index Of A Nonsingular Algebraic Curve, Anar Dosi̇

Turkish Journal of Mathematics

The present paper is devoted to a scheme-theoretic analog of the Fredholm theory. The continuity of the index function over the coordinate ring of an algebraic variety is investigated. It turns out that the index is closely related to the filtered topology given by finite products of maximal ideals. We prove that a variety over a field possesses the index function on nonzero elements of its coordinate ring iff it is an algebraic curve. In this case, the index is obtained by means of the multiplicity function from its normalization if the ground field is algebraically closed.


On The Existence Of $6$-Cycles For Some Families Of Difference Equations Of Third Order, Antonio Linero Bas, Daniel Nieves Roldán Nov 2023

On The Existence Of $6$-Cycles For Some Families Of Difference Equations Of Third Order, Antonio Linero Bas, Daniel Nieves Roldán

Turkish Journal of Mathematics

We prove that there are no $6$-cycles of the form $x_{n+3}=x_i f(x_j,x_k),$ with $i,j,k\in\{n,n+1,n+2\}$ pairwise distinct, whenever $f:(0,\infty)\times (0,\infty)\rightarrow (0,\infty)$ is a continuous symmetric function, that is, $f(x,y)=f(y,x)$, for all $x,y>0$. Moreover, we obtain all the $6$-cycles of potential form and present some open questions relative to the search of $p$-cycles whenever symmetry does not hold.


Dynamical Complexity Of A Predator-Prey Model With A Prey Refuge And Allee Effect, Jianping Gao, Jianghong Zhang, Wenyan Lian Nov 2023

Dynamical Complexity Of A Predator-Prey Model With A Prey Refuge And Allee Effect, Jianping Gao, Jianghong Zhang, Wenyan Lian

Turkish Journal of Mathematics

We consider a predator-prey model with a non-monotonic functional response encompassing a prey refuge and a strong Allee effect on the prey. The multiple existence and stability of interior equilibria are investigated. The bifurcation analysis shows this model can exhibit numerous kinds of bifurcations (e.g., saddle-node, Hopf-Andronov and Bogdanov-Takens bifurcations). It is found that there exist diverse parameter values for which the model exhibits a limit cycle, a homoclinic orbit, and even many heteroclinic curves. The results obtained reveal the prey refuge in the model brings rich dynamics and makes the system more sensitive to parameter values. The main purpose …


Inequalities Involving General Fractional Integrals Of P-Convex Functions, İlknur Yeşi̇lce Işik, Gülteki̇n Tinaztepe, Serap Kemali̇, Gabi̇l Adi̇lov Nov 2023

Inequalities Involving General Fractional Integrals Of P-Convex Functions, İlknur Yeşi̇lce Işik, Gülteki̇n Tinaztepe, Serap Kemali̇, Gabi̇l Adi̇lov

Turkish Journal of Mathematics

The Hermite-Hadamard type inequalities involving fractional integral operations for p-convex functions with respect to another function are studied. Then, the inequalities via Riemann-Liouville and Hadamard fractional integrals are presented specially. Using the obtained results, some inequality relations among special functions including beta and incomplete beta functions, gamma and incomplete gamma functions, and hypergeometric functions are presented.


Cover And Contents Oct 2023

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Phthalocyanines Prepared From 4,5-Dihexylthiophthalonitrile, A Popular Building Block, Derya Topkaya Taşkiran, Zeynel Şahi̇n, Ümi̇t İşci̇, Fabi̇enne Dumouli̇n Oct 2023

Phthalocyanines Prepared From 4,5-Dihexylthiophthalonitrile, A Popular Building Block, Derya Topkaya Taşkiran, Zeynel Şahi̇n, Ümi̇t İşci̇, Fabi̇enne Dumouli̇n

Turkish Journal of Chemistry

Phthalocyanines are tetrapyrrolic artificial porphyrinoids that play major roles in advanced biological and technological applications. Research on this family of dyes is particularly active in Türkiye, with many derivatives being prepared from 4,5-dihexyl-thiophthalonitrile DiSHexPN, which is one of the most popular noncommercially available building blocks for phthalocyanines. This review summarizes the phthalocyanines and their versatile properties and applications that have been published since 1994, when the synthesis of DiSHexPN was first described, to emphasize the importance of this building block in plentiful applications, all with bio-medical or technological impact.


Combination Of Smartphone Digital Image Colorimetry And Uv-Vis Spectrophotometry As Detection Systems With Solidified Floating Organic Drop Microextraction As Preconcentration Method For The Quantification Of Methyl Red In Wastewater Samples, Mi̇ray Bombom, Ayça Gi̇rgi̇n, Buse Tuğba Zaman, Fatma Turak, Sezgi̇n Bakirdere Oct 2023

Combination Of Smartphone Digital Image Colorimetry And Uv-Vis Spectrophotometry As Detection Systems With Solidified Floating Organic Drop Microextraction As Preconcentration Method For The Quantification Of Methyl Red In Wastewater Samples, Mi̇ray Bombom, Ayça Gi̇rgi̇n, Buse Tuğba Zaman, Fatma Turak, Sezgi̇n Bakirdere

Turkish Journal of Chemistry

In this study, a portable smartphone-based digital image colorimetric system (SDIC) was designed and integrated with a solidified floating organic drop microextraction method (SFODME) for the quantification of methyl red in textile wastewater samples. The RGB (red, green, and blue) data were evaluated for each captured image, and the green channel was selected for quantification due to its linear response for the analyte. Under optimal conditions, an acceptable linear range was recorded for the analyte. The proposed method recorded a limit of detection (LOD) value of 0.046 mg/L. The developed microextraction method was also combined with UVVis spectrophotometry, which recorded …


Amplifying The Dielectric Constant Of Shellac By Incorporating Natural Clays For Organic Field Effect Transistors (Ofets), Sunwoo Kim, Cigdem Yumusak, Cristian-Vlad Irimia, Mateusz Bednorz, Esma Yenel, Mahmut Kuş, Ni̇yazi̇ Serdar Sariçi̇ftçi̇, Bong Sup Shim, Mihai Irimia Oct 2023

Amplifying The Dielectric Constant Of Shellac By Incorporating Natural Clays For Organic Field Effect Transistors (Ofets), Sunwoo Kim, Cigdem Yumusak, Cristian-Vlad Irimia, Mateusz Bednorz, Esma Yenel, Mahmut Kuş, Ni̇yazi̇ Serdar Sariçi̇ftçi̇, Bong Sup Shim, Mihai Irimia

Turkish Journal of Chemistry

We demonstrate in this work the practical use of uniform mixtures of a bioresin shellac and four natural clays, i.e. montmorillonite, sepiolite, halloysite and vermiculate as dielectrics in organic field effect transistors (OFETs). We present a thorough characterization of their processability and film forming characteristic, surface characterization, elaborate dielectric investigation and the fabrication of field effect transistors with two classic organic semiconductors, i.e. pentacene and fullerene C60. We show that low operating voltage of approximately 4 V is possible for all the OFETs using several combinations of clays and shellac. The capacitance measurements show an improvement of the dielectric constant …


Metal-Organic Frameworks As Photocatalysts In Energetic And Environmental Applications, Eli̇f Özcan, Zeli̇ha Mermer, Yunus Zorlu Oct 2023

Metal-Organic Frameworks As Photocatalysts In Energetic And Environmental Applications, Eli̇f Özcan, Zeli̇ha Mermer, Yunus Zorlu

Turkish Journal of Chemistry

Metal-organic frameworks (MOFs) are an exciting new class of porous materials with great potential for photocatalytic applications in the environmental and energy sectors. MOFs provide significant advantages over more traditional materials when used as photocatalysts due to their high surface area, adaptable topologies, and functional ability. In this article, we summarize current developments in the use of MOFs as photocatalysts for a variety of applications, such as CO2 reduction, water splitting, pollutant degradation, and hydrogen production. We discuss the fundamental properties of MOFs that make them ideal for photocatalytic applications, as well as strategies for improving their performance. The opportunities …


A Multifunctional Thienothiophene Member: 4-Thieno[3,2-B]Thiophen-3-Ylbenzonitrile (4-Cnphtt), Recep İşçi̇, Turan Öztürk Oct 2023

A Multifunctional Thienothiophene Member: 4-Thieno[3,2-B]Thiophen-3-Ylbenzonitrile (4-Cnphtt), Recep İşçi̇, Turan Öztürk

Turkish Journal of Chemistry

Thieno[3,2-b]thiophene (TT) has been attracting significant attention in the field of organic electronics and optoelectronics. In this study, a useful building block of TT derivative 4-thieno[3,2-b]thiophen-3-ylbenzonitrile (4-CNPhTT), developed by our group and possessing a strong electron-withdrawing 4-CNPh moiety, is reviewed as it has been the source of the development of various organic electronic materials. Some optic and electronic properties are discussed based on electrochemical polymerization of 4-CNPhTT performed using cyclic voltammetry, and spectroelectrochemical measurements are conducted to investigate the optical variations of the polymer film upon doping. Moreover, 4-CNPhTT is clarified by scanning electron microscopy at different magnitudes ranging from …


Water-Soluble Phthalocyanine Photosensitizers For Photodynamic Therapy, İpek Ömeroğlu, Mahmut Durmuş Oct 2023

Water-Soluble Phthalocyanine Photosensitizers For Photodynamic Therapy, İpek Ömeroğlu, Mahmut Durmuş

Turkish Journal of Chemistry

Photodynamic therapy (PDT) is based on a photochemical reaction that is started when a photosensitizing process is activated by the light and results in the death of tumor cells. Solubility is crucial in PDT applications to investigate the physical and chemical characteristics of phthalocyanines, but, unfortunately, most phthalocyanines show limited solubility especially in water. To increase the solubility of phthalocyanines in polar solvents and water, ionic groups such as -SO3 - , -NR3 +, -COO- , and nonionic groups such as poly-oxy chains are frequently added to the peripheral or nonperipheral positions of the phthalocyanine framework. Since water-solubility and NIR-absorbing …


Fluid-Based Wearable Sensors: A Turning Point In Personalized Healthcare, Berfi̇n Vural, İnci̇ Uludağ, Bahar İnce, Canan Özyurt, Funda Öztürk, Mustafa Kemal Sezgi̇ntürk Oct 2023

Fluid-Based Wearable Sensors: A Turning Point In Personalized Healthcare, Berfi̇n Vural, İnci̇ Uludağ, Bahar İnce, Canan Özyurt, Funda Öztürk, Mustafa Kemal Sezgi̇ntürk

Turkish Journal of Chemistry

Nowadays, it has become very popular to develop wearable devices that can monitor biomarkers to analyze the health status of the human body more comprehensively and accurately. Wearable sensors, specially designed for home care services, show great promise with their ease of use, especially during pandemic periods. Scientists have conducted many innovative studies on new wearable sensors that can noninvasively and simultaneously monitor biochemical indicators in body fluids for disease prediction, diagnosis, and management. Using noninvasive electrochemical sensors, biomarkers can be detected in tears, saliva, perspiration, and skin interstitial fluid (ISF). In this review, biofluids used for noninvasive wearable sensor …


Green Catalyst For Clean Fuel Production Via Hydrodeoxygenation, Selva Bi̇lge Yücel, Yusuf Osman Donar, Samed Ergenekon, Beyza Özoylumlu, Ali̇ Sinağ Oct 2023

Green Catalyst For Clean Fuel Production Via Hydrodeoxygenation, Selva Bi̇lge Yücel, Yusuf Osman Donar, Samed Ergenekon, Beyza Özoylumlu, Ali̇ Sinağ

Turkish Journal of Chemistry

The development of new fuel sources to replace nonrenewable fossil fuels has received substantial attention due to the ongoing demand for fossil fuels. Biomass and raw waste materials are crucial sources to produce suitable alternative fuels instead of nonrenewable fuels and offer a greener approach. Therefore, improving the fuel properties of biooils produced from the thermochemical conversion of biomass and raw waste materials is critical as it is used as an alternative to nonrenewable fuel. Developing an economical and eco-friendly method to produce sustainable and renewable oil by improving biooil containing large amounts of phenolic compounds has become imperative. One …


Heterocyclic Molecules With Esipt Emission: Synthetic Approaches, Molecular Diversities, And Application Strategies, Nuretti̇n Mengeş Oct 2023

Heterocyclic Molecules With Esipt Emission: Synthetic Approaches, Molecular Diversities, And Application Strategies, Nuretti̇n Mengeş

Turkish Journal of Chemistry

Excited-state intramolecular proton transfer (ESIPT) is one of the most essential emission processes in most circumstances because of its dual emission band in most cases and its high Stokes shifts. These distinguishing properties make ESIPT-based probes more suitable for a variety of applications, including analyte sensors, solid-state sensing mechanisms, optical technologies, and biomarkers for endogenous or exogenous compounds in various settings. As a result, researchers around the world are working on ESIPT emissions and developing different scaffolds for various applications or industry demands. This field of study is rapidly expanding and there is a need for an up-to-date review of …


Arsenic Speciation By Using Emerging Sample Preparation Techniques: A Review, Muhammad Saqaf Jagirani, Mustafa Soylak Oct 2023

Arsenic Speciation By Using Emerging Sample Preparation Techniques: A Review, Muhammad Saqaf Jagirani, Mustafa Soylak

Turkish Journal of Chemistry

Arsenic is a hazardous element that causes environmental pollution. Due to its toxicological effects, it is crucial to quantify and minimize the hazardous impact on the ecology. Despite the significant advances in analytical techniques, sample preparation is still crucial for determining target analytes in complex matrices. Several factors affect the direct analysis, such as trace-level analysis, advanced regulatory requirements, complexity of sample matrices, and incompatible with analytical instrumentation. Along with the development in the sample preparation process, microextraction methods play an essential role in the sample preparation process. Microextraction techniques (METs) are the newest green approach that replaces traditional sample …


Electrochemical Dna Biosensors Developed For The Monitoring Of Biointeractions With Drugs: A Review, Kadri̇ye Arzum Erdem Gürsan, Muhammed Hüseyi̇n Şentürk, Esma Yildiz Göz, Meltem Maral, Ayla Yildirim, Ayşen Bozoğlu, Burak Kivrak, Nesli̇han Ceren Ay Oct 2023

Electrochemical Dna Biosensors Developed For The Monitoring Of Biointeractions With Drugs: A Review, Kadri̇ye Arzum Erdem Gürsan, Muhammed Hüseyi̇n Şentürk, Esma Yildiz Göz, Meltem Maral, Ayla Yildirim, Ayşen Bozoğlu, Burak Kivrak, Nesli̇han Ceren Ay

Turkish Journal of Chemistry

The interaction of drugs with DNA is important for the discovery of novel drug molecules and for understanding the therapeutic effects of drugs as well as the monitoring of side effects. For this reason, many studies have been carried out to investigate the interactions of drugs with nucleic acids. In recent years, a large number of studies have been performed to electrochemically detect drug-DNA interactions. The fast, sensitive, and accurate results of electrochemical techniques have resulted in a leading role for their implementation in this field. By means of electrochemical techniques, it is possible not only to demonstrate drug-DNA interactions …


Sonophotochemical And Photochemical Efficiency Of Thiazole-Containing Metal Phthalocyanines And Their Gold Nanoconjugates, Nazli Farajzadeh, Hacer Yasemi̇n Yeni̇lmez, Göknur Yaşa Atmaca, Ali̇ Erdoğmuş, Zehra Bayir Oct 2023

Sonophotochemical And Photochemical Efficiency Of Thiazole-Containing Metal Phthalocyanines And Their Gold Nanoconjugates, Nazli Farajzadeh, Hacer Yasemi̇n Yeni̇lmez, Göknur Yaşa Atmaca, Ali̇ Erdoğmuş, Zehra Bayir

Turkish Journal of Chemistry

This study presents the synthesis of some metal {M = Zn(II), Lu(III), Si(IV)} phthalocyanines bearing chlorine and 2-(4-methylthiazol-5-yl) ethoxy groups at peripheral or axial positions. The newly synthesized metal phthalocyanines were characterized by applying FT-IR, 1 H NMR, mass, and UV-Vis spectroscopic approaches. Additionally, the surface of gold nanoparticles was modified with zinc(II) and silicon(IV) phthalocyanines. The resultant nanoconjugates were characterized using TEM images. Moreover, the effect of metal ions and position of substituent, and gold nanoparticles on the photochemical and sonophotochemical properties of the studied phthalocyanines was investigated. The highest singlet oxygen quantum yield was obtained for the lutetium …


Influence Of Soft Segment Structure, Hydrogen Bonding, And Diisocyanate Symmetry On Morphology And Properties Of Segmented Thermoplastic Polyurethanes And Polyureas, Emel Yilgör, İskender Yilgör Oct 2023

Influence Of Soft Segment Structure, Hydrogen Bonding, And Diisocyanate Symmetry On Morphology And Properties Of Segmented Thermoplastic Polyurethanes And Polyureas, Emel Yilgör, İskender Yilgör

Turkish Journal of Chemistry

A comprehensive review of the structure-morphology-property relations in segmented thermoplastic polyurethanes and polyureas (TPU) is provided. Special emphasis is given to the influence of the soft segment structure, polarity, and molecular weight, diisocyanate symmetry and the nature, extent, and strength of hydrogen bonding on the morphology and thermal and mechanical properties of TPUs. Experimental results obtained on composition-dependent TPU morphology and properties by various techniques were also compared by the morphology profiles generated by computational methods such as quantum mechanical calculations and molecular dynamics simulations


Homoprotocatechuate Dioxygenase Active Site: Imitating The Secondary Sphere Base Via Computational Design, Muhammed Buyuktemiz, Yavuz Dede Oct 2023

Homoprotocatechuate Dioxygenase Active Site: Imitating The Secondary Sphere Base Via Computational Design, Muhammed Buyuktemiz, Yavuz Dede

Turkish Journal of Chemistry

Oxidative ring cleavage reactions have attracted great interest and various studies on the catechol ring-cleaving enzyme homoprotocatechuate dioxygenase (HPCD) have been reported in the literature. The available data on how the proton transfer takes place led us to design a potential HPCD model structure. A secondary sphere effect of utmost importance, the assistance of His200, which is critical for the catechol proton to migrate to dioxygen, was cautiously included on the first coordination shell. This was done mainly by modifying the axial ligands in the first coordination shell of HPCD such that the dual basic/acidic role in the proton transfer …


Advanced Tetra Amino (Ata-100) Cobalt(Ii) Phthalocyanine-Based Metallo-Covalent Organic Polymer For Sensitively Detecting Volatile Organic Compounds, Günseli̇ Güney, Gülay Altindemi̇r Kaplan, Ci̇hat Taşaltin, İlke Gürol Oct 2023

Advanced Tetra Amino (Ata-100) Cobalt(Ii) Phthalocyanine-Based Metallo-Covalent Organic Polymer For Sensitively Detecting Volatile Organic Compounds, Günseli̇ Güney, Gülay Altindemi̇r Kaplan, Ci̇hat Taşaltin, İlke Gürol

Turkish Journal of Chemistry

The synthesis and characterization of a novel covalent organic polymer cobalt (II) phthalocyanine (ATA-100) including tetra amino group is described for the first time. This covalent organic polymer (COP) is characterized by FTIR, TGA, RAMAN, PXRD, and SEM-EDS. The developed sensor is tested for acetone, ethyl butyrate, n-hexane, chloroform, and n-butyraldehyde in a range of 80-10,900 ppm. ATA-100 showed the highest sensitivity for ethyl butyrate. The results have confirmed the possibility of utilizing ATA-100 COP-based surface acoustic wave (SAW) sensors for a wide variety of applications, including indoor air quality and environmental monitoring of volatile organic compounds (VOCs).


Determination Of Ketamine Using Melamine-Modified Gold Nanoparticles, Güler Güneş, Zi̇ya Can, Ayşem Arda, Mustafa Reşat Apak Oct 2023

Determination Of Ketamine Using Melamine-Modified Gold Nanoparticles, Güler Güneş, Zi̇ya Can, Ayşem Arda, Mustafa Reşat Apak

Turkish Journal of Chemistry

Ketamine is used in medicine because of its anaesthetic and antidepressant effects at low doses. Unfortunately, due to its narcotic effect when used at high doses, its abuse among young people is increasing. It is also one of the most common drugs used in rape. Therefore, there is a need for fast and inexpensive tests that can be performed on-site. With the advancement of nanotechnology, nanoparticle-based approaches have found their place in selective analyses as in many fields. In the developed method, firstly gold nanoparticles were modified with melamine (AuNPs@Mel). Under optimized conditions, hydrogen bonds formed between ketamine and AuNPs@Mel …


Comparatively Sonophotochemical And Photochemical Studies Of Phthalocyanines With Cationic Substituents On Nonperipheral Positions, Mukaddes Özçeşmeci̇, Ceren Can Karanlik, Ali̇ Erdoğmuş, Esi̇n Hamuryudan Oct 2023

Comparatively Sonophotochemical And Photochemical Studies Of Phthalocyanines With Cationic Substituents On Nonperipheral Positions, Mukaddes Özçeşmeci̇, Ceren Can Karanlik, Ali̇ Erdoğmuş, Esi̇n Hamuryudan

Turkish Journal of Chemistry

The term sonophotodynamic therapy (SPDT) refers to a combination of sonodynamic therapy (SDT) and photodynamic therapy (PDT), in which the efficacy of the treatment is boosted by utilizing the proper amount of a sensitizer that is responsive to both light and ultrasound. Although it has been proven in photophysicochemical studies that SPDT enhances singlet oxygen production, related studies in the literature are very limited. Considering this situation, this study aims to investigate the efficacy of synthesized phthalocyanines in terms of PDT and SPDT. The singlet oxygen quantum values calculated as 0.13 for 5, 0.44 for 6, and 0.61 for 7 …


Synthesis Of New Imine-/Amine-Bearing Imidazo[1,2-A]Pyrimidine Derivatives And Screening Of Their Cytotoxic Activity, Tuğba Güngör, Hazal Nazlican Atalay, Yakup Berkay Yilmaz, Tuğba Tümer, Mehmet Ay Oct 2023

Synthesis Of New Imine-/Amine-Bearing Imidazo[1,2-A]Pyrimidine Derivatives And Screening Of Their Cytotoxic Activity, Tuğba Güngör, Hazal Nazlican Atalay, Yakup Berkay Yilmaz, Tuğba Tümer, Mehmet Ay

Turkish Journal of Chemistry

Imidazo[1,2-a]pyrimidine derivatives bearing imine groups (3a-e) were successfully synthesized in moderate to good yields using microwave-assisted heating. Corresponding amine derivatives (4a-e) were also obtained by the reduction reaction of the imine derivatives (3a-e). All synthesized products were characterized by FT-IR, 1 H NMR, 13C NMR, and LC-MS spectroscopic techniques. In silico ADMET, Lipinski, and drug-likeness studies of the compounds were conducted and all were found to be suitable drug candidates. The cytotoxicity of the potential drug molecules was screened against the breast cancer cell lines MCF-7 and MDA-MB-231 and the healthy model HUVEC by the sulforhodamine B method. According to …


Cibacron Blue F3ga Ligand Dye-Based Magnetic Silica Particles For The Albumin Purification, Nurhak Tatar, Semra Akgönüllü, Handan Yavuz Alagöz, Adi̇l Deni̇zli̇ Oct 2023

Cibacron Blue F3ga Ligand Dye-Based Magnetic Silica Particles For The Albumin Purification, Nurhak Tatar, Semra Akgönüllü, Handan Yavuz Alagöz, Adi̇l Deni̇zli̇

Turkish Journal of Chemistry

Dye-ligand affinity chromatography is among the increasingly popular affinity chromatography based on molecular recognition for the purification of albumin. This study focuses on the binding of Cibacron Blue F3GA ligand dye with magnetic silica particles and purification by separation. Mono-disperse silica particles with bimodal pore size distribution were employed as a high-performance adsorbent for human serum albumin (HSA) protein purification under equilibrium conditions. The synthesized ligand-dye affinity based magnetic silica particles were characterized by electron spin resonance, Fourier-transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer, elemental analysis, and dispersive X-ray analysis. The HSA purification performance of the proposed material …


The Chemical And Electrochemical Stimuli Viologen Substituted Phthalocyanine With Tunable Optical Features1, Özge Di̇lara Ateş, Gülenay Tunç, Ahmet Şenocak, Burcu Dedeoğlu, Mehmet Menaf Ayhan, Ayşe Gül Gürek Oct 2023

The Chemical And Electrochemical Stimuli Viologen Substituted Phthalocyanine With Tunable Optical Features1, Özge Di̇lara Ateş, Gülenay Tunç, Ahmet Şenocak, Burcu Dedeoğlu, Mehmet Menaf Ayhan, Ayşe Gül Gürek

Turkish Journal of Chemistry

In this study, viologen-tetrasubstituted Zn(II) phthalocyanines (PcV1 and PcV2) were designed and synthesized to achieve the tunable optical features via redox-active viologen groups. Several parameters relevant to the evaluation of the tunable optical features have been investigated: UV-Vis, cyclic voltammetry (CV), EPR, square wave voltammetry (SWV), and theoretical analyses. The results showed that upon reductions and oxidations of viologen groups either chemically or electrochemically, the optical features of PcV1 and PcV2 change drastically with switchable processes. These outcomes indicate that achieving control over optical features of large organic chromophores such as Pc with our rational design can be used for …


Phytochemical Analysis And Molecular Docking Studies Of Two Endemic Varieties Of Salvia Sericeotomentosa, Gülbahar Özge Ali̇m Toraman, Halil Şenol, Seçi̇l Yazici Tütüni̇ş, Nur Tan, Gülaçti Topçu Oct 2023

Phytochemical Analysis And Molecular Docking Studies Of Two Endemic Varieties Of Salvia Sericeotomentosa, Gülbahar Özge Ali̇m Toraman, Halil Şenol, Seçi̇l Yazici Tütüni̇ş, Nur Tan, Gülaçti Topçu

Turkish Journal of Chemistry

The use of medicinal plants for treating various diseases dates back thousands of years and has been a part of many cultures around the world. Various parts of plants, including roots, leaves, and flowers, and their extracts have been used to develop remedies to cure different ailments like fever, pain, inflammation, infections, among others. In this research, the aerial parts of both Salvia varieties were extracted with ethanol and water to obtain infusion and decoction, separately. S. sericeotomentosa var. hatayica Celep & Doğan (SH) and Salvia sericeotomentosa Rech. f. var. sericeotomentosa (ST) plants were chemically analyzed for polar compounds using …


Reducible Tungsten(Vi) Oxide-Supported Ruthenium(0) Nanoparticles: Highly Active Catalyst For Hydrolytic Dehydrogenation Of Ammonia Borane, Serdar Akbayrak, Yalçin Tonbul, Sai̇m Özkar Oct 2023

Reducible Tungsten(Vi) Oxide-Supported Ruthenium(0) Nanoparticles: Highly Active Catalyst For Hydrolytic Dehydrogenation Of Ammonia Borane, Serdar Akbayrak, Yalçin Tonbul, Sai̇m Özkar

Turkish Journal of Chemistry

Reducible WO3 powder with a mean diameter of 100 nm is used as support to stabilize ruthenium(0) nanoparticles. Ruthenium(0) nanoparticles are obtained by NaBH4 reduction of ruthenium(III) precursor on the surface of WO3 support at room temperature. Ruthenium(0) nanoparticles are uniformly dispersed on the surface of tungsten(VI) oxide. The obtained Ru0 /WO3 nanoparticles are found to be active catalysts in hydrolytic dehydrogenation of ammonia borane. The turnover frequency (TOF) values of the Ru0 /WO3 nanocatalysts with the metal loading of 1.0%, 2.0%, and 3.0% wt. Ru are 122, 106, and 83 min-1, respectively, in releasing hydrogen gas from …


Synthesis Of Alnustone-Like Diarylpentanoids Via A 4 + 1 Strategy And Assessment Of Their Potential Anticancer Activity, Nesli̇han Çelebi̇oğlu, Özlem Özdemi̇r Tozlu, Hasan Türkez, Hasan Seçen Oct 2023

Synthesis Of Alnustone-Like Diarylpentanoids Via A 4 + 1 Strategy And Assessment Of Their Potential Anticancer Activity, Nesli̇han Çelebi̇oğlu, Özlem Özdemi̇r Tozlu, Hasan Türkez, Hasan Seçen

Turkish Journal of Chemistry

Twelve compounds with a 1,5-diaryl-1-penten-3-one structure were synthesized and their cytotoxic activities were evaluated. The 1,5-diaryl-1-penten-3-one compounds were obtained via in situ enaminations of 4-phenyl-2-butanone and 4-(4-hydroxyphenyl)-2- butanone in the presence of pyrrolidine-AcOH, followed by condensation with six different benzaldehydes. The synthesized compounds were tested for their cytotoxic activity against human glioblastoma (U87-MG), breast (MCF-7), and prostate (PC-3) cancer cell lines. Some of the novel compounds exhibited remarkable cytotoxic action, especially against MCF-7 cancer cells.


Innovative Polymer Engineering For The Investigation Of Electrochemical Properties And Biosensing Ability, Sila Can Osmanoğullari, Sani̇ye Söylemez, Oğuzhan Karakurt, Şeri̇fe Özdemi̇r Hacioğlu, Ali̇ Çirpan, Levent Kami̇l Toppare Oct 2023

Innovative Polymer Engineering For The Investigation Of Electrochemical Properties And Biosensing Ability, Sila Can Osmanoğullari, Sani̇ye Söylemez, Oğuzhan Karakurt, Şeri̇fe Özdemi̇r Hacioğlu, Ali̇ Çirpan, Levent Kami̇l Toppare

Turkish Journal of Chemistry

Subtle engineering for the generation of a biosensor from a conjugated polymer with the inclusion of fluorine-substituted benzothiadiazole and indole moieties is reported. The engineering includes the electrochemical copolymerization of the indole-6-carboxylic acid (M1) and 5-fluoro-4,7-bis(4-hexylthiophen-2-yl)benzo[c][1,2,5]thiadiazole (M2) on the indium tin oxide and graphite electrode surfaces for the investigation of both their electrochemical properties and biosensing abilities with their copolymer counterparts. The intermediates and final conjugated polymers, Poly(M1) [P-In6C], Poly(M2) [P-FBTz], and copoly(M1 and M2) [P-In6CFBTz], were entirely characterized by 1 H NMR, 13C NMR, CV, UV-Vis-NIR spectrophotometry, and SEM techniques. HOMO energy levels of electrochemically obtained polymers were calculated …


Benzimidazol-2-Ylidene Ruthenium Complexes For C-N Bond Formation Through Alcohol Dehydrogenation, Zahid Nawaz, Nevi̇n Gürbüz, Muhammed Naveed Zafar, Namik Özdemi̇r, Beki̇r Çeti̇nkaya, İsmai̇l Özdemi̇r Oct 2023

Benzimidazol-2-Ylidene Ruthenium Complexes For C-N Bond Formation Through Alcohol Dehydrogenation, Zahid Nawaz, Nevi̇n Gürbüz, Muhammed Naveed Zafar, Namik Özdemi̇r, Beki̇r Çeti̇nkaya, İsmai̇l Özdemi̇r

Turkish Journal of Chemistry

A low temperature hydrogen borrowing approach to generate secondary amines using benzimidazole-based N-heterocyclic carbene (BNHC) ruthenium complexes is reported. A series of the piano-stool complexes of the type [(η6 -p-cymene)(BNHC)RuCl2 ] (1a-g) were synthesized via one-pot reaction of the NHC salt precursor, Ag2 O, and [RuCl2 (p-cymene)]2 and characterized using conventional spectroscopic techniques. The geometry of two precursors, [(η6 -p-cymene)(Me4BnMe2 BNHCCH2OxMe)RuCl2 ] (1f) and [(η6 -p-cymene)(Me5BnMe2 BNHCCH2OxMe)RuCl2 ] (1g), was studied by single crystal X-ray diffraction. These catalysts were found to dehydrogenate alcohols efficiently at temperatures as low as 50 °C to allow Schiff-base condensation and subsequent …