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VII. Ulusal Analitik Kimya Kongresi3
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ELSEVIER2
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International Eurasian Conference on Biological and Chemical Sciences (EurasianBioChem 2018)2
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2nd International Conference on Engineering, Natural and Social Sciences ICENSOS1
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5th International Eurasian Conference on Biological and Chemical Sciences (EurasianBioChem 2022)1
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8th Black Sea Basin Conference on Analytical Chemistry (8th BBCAC)1
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ACADEMIC PRESS INC ELSEVIER SCIENCE1
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Elsevier1
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Manisa Celal Bayar Üniversitesi1
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Turkish Chemical Society1
Determination of Formation Constants of Some Metal Complexes of Naphthoquinone Derivatives
Efeoglu, Cagla | Kocagöz, Gülçin | Nural, Yahya | Dincer Kaya, Fadime Nazlı
2025-12-29
Synthesis, biological properties, and acid dissociation constant of novel naphthoquinone–triazole hybrids
Nural, Yahya | Özdemir, Sadin | Demir, Bünyamin | Yalçın, Mustafa Serkan | Erat, Selma
A series of novel 1,4-naphthoquinone–triazole hybrids, N-(3-amino-1,4-dioxo-1,4-dihydronaphthalen-2-yl)-2-(4-R-1H-1,2,3-triazol-1-yl)acetamide, was synthesized by click chemistry in the presence of sodium ascorbate and copper(II) sulfate pentahydrate in 81–94% yield. Various biological properties of the synthesized compounds including DNA binding/cleavage, antioxidant, antibacterial and antifungal properties were evaluated. The DNA binding study was performed using dsDNA and G-quadruplex DNA. All of the compounds showed fluorescence increase in the presence of DNA, regardless of the structure. Up to 2.9 and 2.5 times fluorescence increase upon incubation with double stranded or G-quadruplex DNA was detected for 5f and 5g, respectively. The docking studies performed on dsDNA and G-quadruple...
Novel 1,4-naphthoquinone N-aroylthioureas: Syntheses, crystal structure, anion recognition properties, DFT studies and determination of acid dissociation constants
Gemili, Müge | Nural, Yahya
In this paper, five novel 1,4-naphthoquinone N-aroylthiourea derivatives were synthesized, by the reaction of 2,3-diaminonaphthalene-1,4-dione and aroylisothiocyanates, in excellent yield (88-96%) and characterized by using FT-IR, H-1/C-13 NMR and HRMS. In addition, the molecular structure of one of the 1,4-naphthoquinone N-aroylthiourea compounds was characterized by single crystal X-ray diffraction studies. The absorption spectra of the compounds were determined in DMSO and the dyes have absorption in visible region in the range of 464-477 nm. The chemosensing ability of each of the prepared dyes was assessed by titrating them towards the anions; F-, Cl-, Br-, I- AcO-, CN-, CIO4-, H2PO4-, HSO4-, and NO3-, using spectrophotometric and H-1 NMR titration techniques in DMSO, experimentally. ...
Potentiometric Determination of Acid Dissociation Constants of 2-(pyrrolidin-1-yl)thiazole Derivatives
Nural, Yahya | Gemili, Müge
Physicochemical parameters provide critical information for scientists in the many scientific fields such as drug research studies, the development of analysis methods, etc [1]. The acid dissociation constant (pKa) is one of the most important physicochemical parameters [1-3]. In this study [4], acid dissociation constants of the potential bioactive 2-(pyrrolidin-1-yl)thiazole derivatives were potentiometrically determined at 25.0 ± 0.1 ºC in a 30% (v/v) DMSO-water mixture. The potentiometrically obtained data were used for the calculation of the pKa values using the HYPERQUAD computer program. Three different pKa values were found for the compounds and the pKa1, pKa2 and pKa3 values were obtained in a range of 2.46 (±0.10) - 3.78 (±0.10), 5.61 (±0.07) - 6.77 (±0.08) and 8.50...
Acid dissociation constants of 4-aryl-2-(pyrrolidin-1-yl)thiazole derivatives in dimethyl sulfoxide-water hydroorganic solvent”,
Gemili, Muge | Nural, Yahya
Acid dissociation constants (pKa) are among the important parameters having critical significance in the field of pharmacy, chemistry, biology, medicine etc. due to providing information related to acidity, solubility, lipophilicity, bonding to receptors, transport behavior properties of pharmaceutically important molecules, determining the optimum conditions in the development of analytical methods, and understanding the interactions between ligands and metal ions in complexes [1-3]. The thiazole and pyrrolidine scaffolds are intensively studied in drug research, and both of these pharmacophore groups exhibited a wide range of pharmacological activities such as antimicrobial, anticancer activities [3-6]. As a continuation of our previous work [3], in this study, three acid dissoci...
Synthesis of Bis-Thiourea Derivatives and Their Acid Dissociation Constants
Efeoglu, Cagla | Tiken, Şit | Nural, Yahya
2025-12-31
Potentiometric Determination of Stability Constants of Co(II), Cu(II), Ni(II) and Zn (II) Complexes of Methyl 5-methyl-4,6-dioxo-2-(5-(2-oxo-2H-chromene-3-carbonyl)-4-phenylthiazol-2-yl)-3,3-diphenyl-octahydro pyrrolo[3,4-c]pyrrole-1-carboxylate
Gemili, Muge | Nural, Yahya
The stability constant parameters have an important place in drug research and development studies. The stability constant provides information to understand the formation and stability of bonds in a complex and to understand the bonding mechanisms, and to determine the concentration of the components present in a mixture in equilibrium [1-3]. In this study, stability constants of Co(II), Cu(II), Ni(II) and Zn(II) complexes of methyl 5-methyl-4,6-dioxo-2-(5-(2-oxo-2H-chromene-3-carbonyl)-4-phenylthiazol 2-yl)-3,3-diphenyl-octahydropyrrolo[3,4-c]pyrrole-1-carboxylate were potentiometrically determined at 25.0 ± 0.1 ºC in a 40% (v/v) DMSO-water mixture. The potentiometrically obtained data were used for the calculation of the stability constants values using the HYPERQUAD comput...
Fused yapıda pirolidin-pirolidindion halka sistemi sübstitüentli N-karbamotiyolbenzamid türevlerinin Pt(II) ve Ni(II) komplekslerinin oluşum sabitlerinin belirlenmesi
Gemili, Müge | Nural, Yahya | Döndaş, Hacı Ali
Kompleks kararlılık sabiti olarak bilinen kompleks oluşum sabitteri, ınetallerin ve ligandlann kompleks oluşturma istekleri, koordinasyonlan, kompleks molekiillerin çöziiniirliikleri gibi birçok özellikleri hakkında bilgi vermehcdirı. Metal-ligand kararlılık sabitleri potansiyomelrik, spektrofotomctrik ve kondiiltometrik gibi farktı birçok yöntemle bclirlenebitmektedir'. Geçiş mctali komplckslerinin biyolojik §isteırıleldcki farmakolojik özelliklerinden dolay farmasötik kimyada önemli bir role sahiptir3. Bıınırnta biılikte, geniş spektrum biyotojik özelliktere sahip olduğu bilinen y'y'-Karbamotiyolbenza mid tiirevlerinin sensör ve saflaşürma için uygunluklanndan dolayı analitik kimyada ve komplekslcşmeye yatkınlıklanndan dolay kooıdinasyon kimyasında da gün geçtikçe ...
New naphthoquinone thiazole hybrids as carbonic anhydrase and cholinesterase inhibitors: Synthesis, crystal structure, molecular docking, and acid dissociation constant
Efeoğlu, Çağla | Selçuk, Özge | Demir, Bünyamin | Nural, Yahya
In this study, N-[3-(3-amino-1,4-dioxo-1,4-dihydronaphthalen-2-yl)-4-R-thiazol-2(3H)-ylidene]-2,6-difluorobenzamide derivatives as new 1,4-naphthoquinone thiazole hybrids were synthesized by reacting of N-[(3-amino-1,4-dioxo-1,4-dihydronaphthalen-2-yl)carbamothioyl]-2,6-difluorobenzamide with various α-bromoketones in 76–92% yields. Their molecular structures were characterized by 1H NMR, 13C NMR, 19F NMR, FT-IR, and HRMS, and the stereochemistry of one of the hybrids was determined by single crystal x-ray diffraction study. These synthesized new compounds (3a–e) were found to be effective inhibitor molecules for cholinesterases (butyrylcholinesterase (BChE) and acetylcholinesterase (AChE)), and carbonic anhydrase I and II (hCA I and hCA II) enzymes. KI values were found to be in the range...
Tetrahidropirolo[3,4-b]pirol-4,6-dion halka sistemi sübstitüentli N-karbamotiyolbenzamid türevlerinin asit iyonlaşma sabitlerinin belirlenmesi
Belveren, Samet | Nural, Yahya | Döndaş, Hacı Ali
İlaç sanayisinde çok fazla sayıda orijinal bileşiğin geliştirilmesi ve bu alandaki ihtiyacın karşılanması için hızla gelişen bilgisayar destekli ilaç dizaynı ve kombinatoryal kimya metotları için kritik bilgiler taşıyan iyonlaşma sabitleri ile ilgili yapılan çalışmalar gün geçtikçe artmaktadır. İlacın vücudun değişik ortamlarındaki davranışları hakkında önemli bilgiler veren iyonlaşma sabiti, ilaçların analizinde optimum koşulların belirlenmesinde de kritik bir öneme sahiptir1. Heterosiklik yapıda olan ve bir azot atomu bulunduran pirolidin ile pirolidin halkasında iki karbonil grubu bulunduran pirolidindionlar biyolojik öneme sahip çok sayıda bileşiğin yapısında yer almaktadırlar. Bunların potansiyel biyoaktif yapılar olmalarından dolayı, bu iki yapıyı da içerecek moleküllerin sen...
New naphthoquinone thiazole hybrids as carbonic anhydrase and cholinesterase inhibitors: Synthesis, crystal structure, molecular docking, and acid dissociation constant
Efeoğlu, Çağla | Selçuk, Özge | Demir, Bünyamin | Nural, Yahya
In this study, N-[3-(3-amino-1,4-dioxo-1,4-dihydronaphthalen-2-yl)-4-R-thiazol-2(3H)-ylidene]-2,6-difluorobenzamide derivatives as new 1,4-naphthoquinone thiazole hybrids were synthesized by reacting of N-[(3-amino-1,4-dioxo-1,4-dihydronaphthalen-2-yl)carbamothioyl]-2,6-difluorobenzamide with various α-bromoketones in 76–92% yields. Their molecular structures were characterized by 1H NMR, 13C NMR, 19F NMR, FT-IR, and HRMS, and the stereochemistry of one of the hybrids was determined by single crystal x-ray diffraction study. These synthesized new compounds (3a–e) were found to be effective inhibitor molecules for cholinesterases (butyrylcholinesterase (BChE) and acetylcholinesterase (AChE)), and carbonic anhydrase I and II (hCA I and hCA II) enzymes. KI values were found to be in the range...
Acid Dissociation Constants of 5,5-Diphenylpyrrolidine NAroylthioureas and Stability Constants of their Pt(II) and Ni(II) Complexes in Acetonitrile-Water Hydroorganic Solvent
Ersen, Duygu | Gemili, Muge | Nural, Yahya
In this study, acid dissociation constants of 5,5-diphenylpyrrolidine N-aroylthiourea derivatives, exhibiting anti(myco)bacterial activity, were determined by potentiometric titration in 30% (v/v) acetonitrile-water hydroorganic solventat 25 ± 0.1 °C, at an ionic background of 0.1 mol / L of NaCl using the HYPERQUAD computer program. Three acid dissociation constants were determined for each compound 1a-e and we suggest that these acid dissociation constants are related to the carboxyl, enol and enthiol groups. Stability constants of their Pt(II) and Ni(II) complexes were also determined by potentiometric titration under the same conditions stated above using the HYPERQUAD computer program. The ligands behave as bidentate and bind to the metal atom via the S and O atoms. In various p...
Synthesis and Determination of Acid Dissociation Constants of Bis-Acyl Thiourea Derivatives
Efeoglu, Cagla | Tiken, Şit | Nural, Yahya
N,N'-((dodecane-1,12-diylbis(azanediyl))bis(carbonothioyl))bis(4-nitrobenzamide) 5 and N,N'-((dodecane-1,12-diylbis(azanediyl))bis(carbonothioyl))bis(3-nitrobenzamide) 6 as bis acyl thiourea derivatives were synthesized and their molecular structures were characterized using 1H NMR, 13C NMR, COSY, DEPT, HMQC, FT-IR, and HRMS techniques. The acid dissociation constants (pKa) of the bis-acyl thiourea derivatives 5, 6 were determined potentiometrically and spectrophotometrically. The pKa values of products 5, 6 were determined in 50% (v/v) dimethyl sulfoxide–water hydro-organic solvent in the presence of 0.1 molL1 ionic strength of NaCl and in the acidic medium at 25±0.1 °C, and two pKa values were calculated for each compound with the HYPERQUAD computer program using the data obtai...
Potansiyometrik Titrasyon Metoduyla Etanol-Su Çözücü Sisteminde Tiyohidantoin Türevi Bileşiklerin İyonizasyon Sabitlerinin İncelenmesi
Nural, Yahya | Döndaş, Hacı Ali
Bir maddeıiı izikokimyasal özelliklerini! belirleımesinde önemli biı yere sahip olan iyonizasyon sabitinin [1, 2], steıeokimyasal ve konformasyon yapı beliılenmesi, biyiıkimyarla eızimieliı aktif merkezlerinin belirlenmesi [2], saflaştrma plosesleri, biieşiklerin kimyasal ıeakiviteleri ve komatograik ay:mıalar heklonila da önemlli bi]gileI verdiğ literatilıde yer ı'lmektadg [3]. Bununla birlikte, iyoıizasyon sabiti, bir ilacm biyolojik sistem içrisinde etki edeceği bölgeye taşEmasl, bölgedeki deı§imi ve metabolizmasu ilacıı, genellikle iyonize formda" iyonik ve iyon_dipol bağlan yapaıak leseptüle etkilştiğ ilikkate ılındığnda" biyolojik si§eıılerle etkileşmesinde de rol alan öıemli fzikokimyasal özelliklerinden biri olduğu da literatijıde yeı nlrnaktadıı [4]. Tiyohidantoin ve...
Determination of Acid Dissociation Constants (pKa) of Bicyclic Thiohydantoin-Pyrrolidine Compounds in 20% Ethanol-Water Hydroorganic Solvent
Nural, Yahya | Dondas, Haci Ali | Belveren, Samet | Gemili, Muge
The acid dissociation constants of potential bioactive fused ring thiohydantoin- pyrrolidine compounds were determined by potentiometric titration in 20% ( v/ v) ethanol- water mixed at 25 +/- 0.1(0) C, at an ionic background of 0.1 mol/ L of NaCl using the HYPERQUAD computer program. Proton affinities of potential donor atoms of the ligands were calculated by AM1 and PM3 semiempiric methods. We found, potentiometrically, three different acid dissociation constants for 1a- f. We suggest that these acid dissociation constants are related to the carboxyl, enol, and amino groups.
Polisübstitüe metil 2-(benzoilkarbamotiyol)-4,6-diksooktahidropirolo[3,4-c]pirol-1-karboksilat türevlerinin asit iyonlaşma sabitlerinin belirlenmes
Gemili, Müge | Nural, Yahya | Döndaş, Hacı Ali
Asit iyonlaşrna sabiti (pK.), molekiili.in asitliği, çtizünebilirliği, lipofilikliğ ile birlikte birçok özelliğ hakhnda bilgiler veren önemli bir parametredirl. Ayrıca, biı ilacın eıki edeceği bölgeye taşınması, bölgedeki derişiıni gibi bilgilerin yaıı sır4 ilaçlaruı iyonik ve iyon{ipol bağlan yaparak reseptörle etkileştiğ dikkate alınüğında asitlik sabilinin önemi düa da artmaktadır'. Biyoaktif özellik gösteren bileşiklerin çok büyük bir krsmı yapılannda azot atomu bulundurmakta ve ilaç Aı{e çalışmalannda azot atomu bulunduıan bileşikler önemli bir yer teşkil etmektedir. Yapısında bir azot atomu bu[unduran beş üyeli heterosiklik bir yapıda olan pirolidin halkası ve tiirevleri ilaç araştırmalannuı en önerıli aıaştırma alanlanndan biridir]. Bu çalışmada daba önceki çatışmalanmı...