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Öğe DBU-catalyzed synthesis of novel 2-amino-3-nitrile-4H-chromenes(Walter De Gruyter Gmbh, 2017) Koz, Gamze; Koz, ÖmerA simple method via the base-catalyzed Michael addition of nitroalkanes to 2-iminochromenes was developed, which leads to the production of highly functionalized 2-amino-3-nitrile-4H-chromenes in good yields.Öğe Design and Synthesis of ?-O-Glucosylated 5-(Arylidene)-6-Aminouracils: Towards Water-Soluble 8-Aryl Xanthines as Effective Enzyme Inhibitors(Wiley-V C H Verlag Gmbh, 2024) Poslu, Ayse Halic; Ertik, Onur; Abul, Nurgul; Telli, Fatma Cetin; Gulcin, Ilhami; Koz, Omer; Koz, Gamze8-Aryl xanthines are selective enzyme inhibitors modified from naturally occurring methylxanthines. However, the low water solubility of substituted xanthines restricts their clinical applications. We developed a strategy to improve the water solubility of biologically privileged 8-aryl xanthines. A series of glucosylated 5-(arylidene)-6-aminouracil was synthesized as 8-aryl-1,3-dimethyl xanthine precursors and fully characterized with spectroscopic methods. Koenigs-Knorr reaction was used to synthesize beta-O-glucosylated aromatic aldehydes which were then reacted with 5,6-diamino-1,3-dimethyluracil to obtain the corresponding 5-(arylidene)-6-aminouracils. The strategy was validated by the ring-closing reaction of a beta-O-glucosylated 5-(arylidene)-6-aminouracil derivative with iodine (I-2) in dimethoxyethane. The water solubility of the glucosylated 8-aryl-1,3-dimethyl xanthine and its non-glycosylated counterpart was compared. Glucosylation improved the water solubility of the compound. The effect of glucosylation on the bioactivity of the compounds was investigated by measuring their inhibition effect on some common enzymes. The glucosylated 8-aryl xanthine demonstrated significantly better efficiency. Molecular docking was performed to elucidate the ligand-protein interactions. Since the target enzymes are primarily related to brain disorders, the blood-brain barrier (BBB) penetration ability of 8-aryl xanthine partners was investigated. According to adsorption, distribution, metabolism, excretion, and toxicity (ADMET) predictions, glucosylated 8-aryl xanthine was found to be BBB permeable.Öğe Discovery of a Uracil-Derived Small Organic Ligand with Cytotoxic Effect on Human PC-3 Cell Lines via Apoptosis(Wiley-V C H Verlag Gmbh, 2024) Poslu, Ayse Halic; Balaban, Rumeysa; Nalbantsoy, Ayse; Ertik, Onur; Cecener, Gulsah; Koz, Omer; Koz, GamzeA series of novel 6-amino-5-salicylidene uracils (1-19) were efficiently synthesized from the condensation reaction of 5,6-diamino-1,3-dimethyluracil with substituted salicylaldehydes. The structural characterization of the compounds was performed with spectroscopic methods and elemental analysis. All compounds were evaluated for their in vitro cytotoxic activity against PC-3 (human prostate adenocarcinoma), A549 (human alveolar adenocarcinoma) and SHSY-5Y (human neuroblastoma) cancer cell lines. 3,5-di-tert-Butylsalicylaldehyde derived salicylideneuracil (6ASU-8) showed promising cytotoxic activity against PC-3 cells with an IC50 value of 1.53 +/- 1.01 mu M, compared to doxorubicin, which had an IC50 value of 3.77 +/- 1.34 mu M. 6ASU-8 induced cell cycle arrest at the G2/M phase and promoted apoptosis in PC-3 cells (p<0.05*). Molecular docking results supported the experimental data, indicating that 6ASU-8 is more effective than doxorubicin. Additionally, in silico ADME analysis revealed that 6ASU-8 possesses acceptable predictive physicochemical properties.Öğe Electrochemical Performance of a New Triazole Functionalized Ferrocene in Aqueous Redox Flow Batteries(Wiley, 2025) Eken, Taha Yasin; Gonzalez, Gabriel; Peljo, Pekka; Koz, GamzeA new 1,2,3-triazole functionalized ferrocene (1,2,3-TAFc) produced by Cu(I)-catalyzed click reaction was investigated as positive electrolyte for aqueous organic flow batteries (AOFBs). The molecule is highly soluble in 1 M hydrochloric acid and displays high electrochemical reversibility. 1,2,3-TAFc demonstrated good stability during cycling with a low capacity decay (0.011%/cyc, 3.0%/day) and high Coulombic efficiency (99.4%) over 280 cycles when tested in a flow battery at low concentration. This low capacity decay was attributed to the instability of ferrocene. These findings indicate that a stable and water-soluble catholyte for AOFBs can be obtained with structural modifications of 1,2,3-TAFc. A new type of ferrocene catholyte for AOFBs based on a 1,2,3-triazole moiety was introduced. 1,2,3-TAFc was prepared easily via click chemistry with a one-pot, two steps reaction sequence with 73% overall yield. The CV and flow battery experiments demonstrated the reversible and stable nature of the material. The cycling battery tests show a high stability of 1,2,3-TAFc in acidic electrolyte with low capacity decay (0.011%/cyc) and high Coulombic efficiency (99.4%).imageÖğe Enantioselective synthesis of 2-amino-4-(nitromethyl)-4H-chromene-3-carbonitriles from 2-iminochromenes(Taylor & Francis Inc, 2016) Koz, Gamze; Koz, Ömer; Coskun, NecdetA series of medicinally important 2-amino-4-(nitromethyl)-4H-chromene-3-carbonitriles were synthesized using enantioselective conjugate addition of nitromethane to 2-iminochromenes. The reactions were performed using L8-Cu (II) catalytic system and moderate to good enantioselectivities (62-88%) and yields (66-96%) were obtained.Öğe GC-MS Analysis of n-Hexane Extract of Saponaria prostrata WILLD. subsp. anatolica HEDGE(2018) Koz, GamzeThe chemical constituents of n-hexane extract of S. prostrata WILLD. subsp. anatolica HEDGE which is an endemic species to Turkey was determined using GC-MS analysis. Twenty six components were identified with alpha-linolenic acid methyl ester and palmitic acid methyl ester as the most abundant components.Öğe GC-MS Analysis of N-Hexane Extracts of Turkish Ankyropetalum Species(2017) Koz, Gamze; Koz, ÖmerThe chemical constituents of crude n-hexane extracts of three Ankyropetalum species, Ankyropetalum gypsophiloides Fenzl, Ankyropetalum arsusianum Kotschy Ex Boiss. and Ankyropetalum reuteri Boiss. Et Hausskn. from Turkey was determined using GC-MS analysis. Thirty three components were identified with Palmitic Acid Methyl Ester and Oleic Acid Methyl Ester as the most abundant components.Öğe L-(+)-Tryptophan methyl ester derived polymeric microbeads as an efffiicient heterogeneous catalyst for green synthesis of 2-amino-4-(nitromethyl)-4H-chromene-3-carbonitriles(Tubitak Scientific & Technological Research Council Turkey, 2022) Poslu, Ayse Halic; Osman, Bilgen; Kaya, Yunus; Koz, Omer; Koz, GamzeThe cross-linked microbeads with average diameter of 106-300 mu m, [poly(EGDMA-MATrp)], were obtained by copolymerization reaction of N-methacryloyl-L-(+)-tryptophan methyl ester (MATrp) with ethylene glycol dimethacrylate (EGDMA) and successfully applied as a heterogeneous catalyst in conjugate addition reaction of nitromethane to substituted 2-iminochromenes in aqueous media. A variety of 2-amino-4-(nitromethyl)-4H-chromene-3-carbonitriles has been synthesized in good yields. Polymeric microbeads were very durable and reused 5 times without a significant loss of activity. DFT calculations and experimental results revealed the significant role of Tr-Tr interactions as well as hydrogen bonding in the reaction mechanism.Öğe N-Boc-Amino Acid Mediated Morita-Baylis Hillman reaction of methylphenyl glyoxylate(2023) Koz, Gamze; Coskun, NecdetThe organocatalyzed Morita-Baylis Hillman (MBH) reaction of ?-keto esters is a challenging carbon-carbon bond-forming reaction. We developed a catalytic system for the MBH reaction of methylphenyl glyoxylate with methyl vinyl ketone in a polar aprotic solvent. We used N-Boc-L-pipecolinic acid as a proton transfer mediator and 4-dimethylaminopyridine as the tertiary amine catalyst. We obtained the MBH adduct with a 66% yield in 48h. We proposed a detailed reaction mechanism involving a transition state that includes the hydrogen transfer by the acid functional group of N-Boc-L-pipecolinic acid.Öğe Regio- and diastereoselective synthesis of (E)-3-(2-aminochromen-4-yl)-6-aryl-substituted fulvenes(Verlag der Zeitschrift fur Naturforschung, 2016) Koz, Gamze; Şahin, O.; Coşkun, N.A practical base-catalyzed route was developed for the regio- and diastereoselective synthesis of (E)-3-aminochromene-6-aryl-disubstituted fulvenes in high yields up to 94% starting with the Michael addition of cyclopentadiene to 2-iminochromenes in the key step. © 2016, Verlag der Zeitschrift fur Naturforschung. All rights reserved.Öğe Structural characterization and biological evaluation of uracil-appended benzylic amines as acetylcholinesterase and carbonic anhydrase I and II inhibitors(Elsevier, 2023) Bulut, Zafer; Abul, Nurgul; Poslu, Ayse Halic; Gulcin, Ilhami; Ece, Abdulilah; Ercag, Erol; Koz, GamzeA series of novel uracil-appended benzylic amines were synthesized through reductive amination with moderate to good yields (30-84% yields). In situ prepared 5-(arylidene)-6-aminouracils with the condensation reaction between 5,6-diamino-1,3-dimethyluracil and substituted salicylaldehydes were reduced by excess sodium borohydride. All of the compounds were characterized using FT-IR, H-1 NMR, C-13 NMR spectroscopy and elemental analysis. The inhibition abilities of novel uracil-appended benzylic amines (1-9) were evaluated against acetylcholinesterase (AChE) and human carbonic anhydrase I and II (hCA I and II) isoenzymes that are linked to some global disorders such as Alzheimer's disease (AD), epilepsy, diabetes and glaucoma. The compounds exhibited inhibition profiles with K-i values ranging from 2.28 +/- 0.41 nM to 5.25 +/- 0.75 nM for AChE, 36.10 +/- 5.22-110.31 +/- 54.81 nM for hCA I and 16.33 +/- 4.91-72.03 +/- 28.86 for hCA II. Tacrine was used as a reference inhibitor for AChE and exhibited a K-i value of 2.59 +/- 0.92 nM against the AChE enzyme. On the other hand, Acetazolamide was used as a standard inhibitor towards hCA I and hCA II isoforms with K-i values of 31.38 +/- 8.56 nM and 18.72 +/- 1.67 nM, respectively. The results of enzyme inhibition associated with some global metabolic diseases indicate that novel uracil-appended benzylic amines may have the potential to develop new drugs to treat some common diseases such as Alzheimer's disease (AD), epilepsy and glaucoma. Molecular docking simulations were conducted to explain the binding interactions of compounds with AChE, hCA I and hCA II. Pharmacokinetic profiles were predicted to be within the acceptable ranges. (c) 2023 Elsevier B.V. All rights reserved.Öğe Structural characterization, cytotoxic and enzyme inhibitory profile of a novel triazole-linked ferrocene hybrid of 18?-glycyrrhetinic acid(Pergamon-Elsevier Science Ltd, 2025) Ozturk, Zehra; Yildiz, Yaren; Abul, Nurgul; Ertik, Onur; Ari, Ferda; Gulcin, Ilhami; Koz, Gamze18 beta-Glycyrrhetinic acid (GA) is a pentacyclic triterpene which was obtained from the roots of Glycyrrhiza glabra known for its diverse pharmaceutical applications. The primary aim of this study is to enhance the pharmaceutical properties of GA by modifying it with a 1,2,3-triazole-functionalized ferrocene moiety. The hybrid compound 3 was synthesized by amide functionalization of GA at the C-30 position with ferrocene, linked via a 1,4-disubstituted 1,2,3-triazole bridge. Additionally, the C-3 hydroxyl group of GA was converted into an acetyl ester. The hybrid compound 3 was characterized using FT-IR, NMR (1H and 13C) and HR-MS. The aim of the modification was to enhance the cytotoxic and enzyme inhibitory effects of GA. 1,2,3,-Triazole substituted ferrocene (1), C-3 acetylated GA and the hybrid compound 3 were tested on A549, MCF-7, HCT-116, and PC-3 cancer cell lines. MCF-7 and HCT-116 cells showed the highest sensitivity to the compounds. Compound 3 showed more cytotoxicity than both GA and compound 1 with IC50 values of 23.97 and 50 mu M in MCF-7 and HCT-116 cells, respectively. Morphological analysis indicated that compound 3 induced apoptotic cell death. In addition, the inhibitory effect of compounds on carbonic anhydrase I-II isoenzymes (hCAI-II), acetylcholinesterase/butyrylcholinesterase (AChE/BChE) enzymes, and alpha-glucosidase was tested. According to the results, compound 3, exhibited the strongest inhibitory properties for all enzymes tested with IC50 values of 0.0323, 0.3058, 0.0078, 0.0090 and 0.0120 mu M, respectively. Molecular docking studies were performed to investigate the ligand-target protein interactions. Incorporating an organometallic sandwich-like compound ferrocene into GA via a 1,2,3-triazole bridge appears to be an effective strategy for modifying and enhancing its bioactivity.Öğe Surface Decoration of Cellulose With Trifluoromethylphenyl Substituted Thiourea: A Robust Hydrogen-Bonding Catalyst in Conjunction With L-Proline for the Asymmetric Direct Mannich Reaction(Wiley, 2024) Poslu, Ayse Halic; Koz, GamzeCellulose is one of the most abundant biopolymers in nature. Despite being the subject of research in various fields, it is not as famous as chitosan in catalyst design. Herein, a novel thiourea-functionalized cellulose (CTU-6) was synthesized as a robust hydrogen bonding catalyst with the degree of substitution (DS) of 0.84. CTU-6 was characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), x-ray powder diffraction (XRD), proton nuclear magnetic resonance spectroscopy (1HNMR), solid-state cross-polarization magic angle spinning carbon-13 nuclear magnetic resonance (CP/MAS 13C-NMR), thermal gravimetric analysis (TGA) and elementel analysis. CTU-6 catalyzed the direct asymmetric Mannich reaction between acetone, aniline, and various aromatic aldehydes in cooperation with L-proline. The reaction exhibited excellent enantioselectivity, achieving up to 98% enantiomeric excess (ee) at room temperature. Incorporating trifluoromethylphenyl-substituted thiourea into the cellulose framework leverages its ability to form hydrogen bonds, thereby enabling precise control over the asymmetric induction. This study highlights the potential of cellulose-based catalysts in advancing asymmetric synthesis and their versatility in various organic reactions in cooperation with small chiral ligands. This synergy not only facilitates the efficient catalytic process but also improves the stereochemical outcomes of the reactions. This method underscores the importance of utilizing renewable and versatile cellulose materials in combination with chiral auxiliaries to achieve high levels of enantioselectivity.Öğe Synthesis and biological evaluation of novel salicylidene uracils: Cytotoxic activity on human cancer cell lines and inhibitory action on enzymatic activity(John Wiley and Sons Inc, 2024) Poslu, Ayşe Halıç; Aslan, Şafak Esra; Koz, Gamze; Şentürk, Esra; Koz, Omer; Şentürk, Murat; Nalbantsoy, A. Ş.A series of salicylidene uracil (1–18) derived from 5-aminouracil and substituted salicylaldehydes were analyzed for cytotoxic activity and enzyme inhibitory potency. Nine out of eighteen derivatives (6–8, 10, 12–15, 18) are novel molecules synthesized for the first time in this work, and other derivatives were previously synthesized by our group. The compounds were characterized by Proton nuclear magnetic resonance, carbon nuclear magnetic resonance, fourier transform infrared spectroscopy, and elemental analysis. All compounds were tested for their in vitro cytotoxicity against PC-3 (human prostate adenocarcinoma), A549 (human alveolar adenocarcinoma), and SHSY-5Y (human neuroblastoma) cancer cell lines and the nontumorigenic HEK293 (human embryonic kidney cells) cell line. The 3,5-di-tert-butylsalicylaldehyde derived compound (8) was toxic to PC-3 human prostate adenocarcinoma cells, showing a promising IC50 value at 7.05 ± 0.76 ?M. The present study also aimed to evaluate the inhibitory effects of the compounds against several key enzymes, namely carbonic anhydrase I and II (CA I and CA II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and glutathione reductase (GR), which are implicated in various global disorders, such as Alzheimer's disease, epilepsy, cancer, malaria, diabetes, and glaucoma. The inhibitory profiles of the tested compounds were assessed by determining their Ki values, which ranged from 2.96 to 9.24 nM for AChE, 3.78 to 12.57 nM for BChE, 8.42 to 25.74 nM for CA I, 7.24 to 19.74 nM for CA II, and 0.541 to 1.124 ?M for GR. Molecular docking studies were also performed for all compounds. Most derivatives exhibited much more effective inhibitory action compared with clinically used standards. Thus, our findings indicate that the salicylidene derivatives presented in this study are promising drug candidates that need further evaluation. © 2023 The Authors. Archiv der Pharmazie published by Wiley-VCH GmbH on behalf of Deutsche Pharmazeutische Gesellschaft.Öğe Synthesis and Molecular Docking Studies of Novel 5-Arylideneaminouracils(Maik Nauka/Interperiodica/Springer, 2019) Koz, GamzeA series of novel 5-arylideneaminouracils is synthesized from 5-aminouracil and substituted salicylaldehydes, and characterized by spectroscopic methods. DNA interactions of model molecules are explored using molecular docking simulations that reveal that these types of molecules can act as DNA groove binders.Öğe Synthesis, spectroscopic analysis, quantum chemical calculations and in silico biological activity studies of a new series of 8-aryl xanthine(Elsevier, 2024) Bilkan, Mustafa Tugfan; Najeeb, Hamsa Abdullah; Poslu, Ayse Halic; Bilkan, Cigdem; Koz, GamzeXanthines and its derivatives are important bronchodilator agents in treating asthma and bronchitis. In this work, four new 8 -aryl xanthine derivatives were synthesized and characterized using spectroscopic techniques (FT-IR, NMR) and elemental analysis. Density Functional Theory (DFT) approach is a reliable way to predict the physicochemical and biological properties of the structures. Investigations on the molecular structure, electronic and vibrational characteristics, UV -visible absorption bands, molecular electrostatic potential maps, and frontier molecular orbital analysis of 8 -aryl xanthines were performed using DFT/B3LYP level of theory with 6-311++G (d,p) basis set. The theoretical data and experimental observations were in good agreement. In addition, druglikeness, ADME, and toxicity parameters were calculated to reveal the biological potential of the compounds.Öğe Synthesis, Structural Calculations and Molecular Docking Studies of a Novel Uracil Derived Organic Molecule(2018) Koz, GamzeAnovel uracil derived compound, (E)-5-((3-chloro-2-hydroxybenzylidene)amino) pyrimidine-2,4(1H,3H)- dione, was synthesized and characterized using spectroscopic techniques. The interaction of the molecule with DNA was explored using computational methods which revealed that the molecule could act as a groove binder. The physicochemical properties of the molecule such as frontier molecule orbitals and chemical reactivity parameters were also investigated.Öğe Yeni Urasil Türevlerinin Aktivite Yönlendirmeli Sentezi(2021) Koz, Gamze; Koz, Ömer; Telli, Fatma; Doğan, Berkay; Bulut, ZaferGrubumuzda yapılan güncel çalışmalar, in silico molekül modellemeleri ile DNA?ya bağlanma potansiyellerinin yüksek olduğu belirlenen küçük organik moleküllerin sentez, yapı tayini ve anti kanser aktivite çalışmalarını içermektedir. Son projemizde, bu yaklaşımla tasarlanan yeni urasil türevi Schiff bazlarının (5AAU) sentez ve yapı tayini gerçekleştirilmiştir. 5-aminourasil ve 5,6-diamino-1,3-dimetilurasil kullanılarak hazırlanan 38 adet yeni urasil türevinin anti kanser aktivite taraması tamamlanmış ve prostat kanser hücresi (PC3) üzerinde doksorubisinden yaklaşık 4 kat daha etkili olan ve sağlıklı hücrelere (HEK293) 5 kat daha az zarar veren öncü bir molekül belirlenmiştir. Diğer türevlerin de farklı kanser hücre hatlarında değişen oranlarda aktivite gösterdiği saptanmıştır. Bu araştırmadan elde ettiğimiz sonuçlara göre, anti kanser aktivitesi en yüksek olan bileşiğin, aynı zamanda organik çözücülerdeki çözünürlüğü en yüksek türev olduğu belirlenmiştir. Bu proje kapsamında, anti kanser aktivite çalışmalarından elde ettiğimiz verilerin yönlendirmesi ile benzer moleküllerin, su ve yaygın organik çözücülerde daha yüksek çözünürlüğe sahip olması beklenen yeni 5,6-diamino-1,3-dimetilurasil türevlerinin hazırlanması ve yapı tayininin yapılması planlanmıştır. Bu plan dâhilinde 2 farklı bileşik grubunun sentezi gerçekleştirilmiştir. Hedef urasil türevleri Proje kapsamında 14 adet şeker türevi ariliden urasil ve 10 adet urasil amin bileşiği hazırlanmıştır. Spektroskopik yöntemler ve elementel analiz ile bileşiklerin yapı tayini gerçekleştirilmiştir. Yapılan çözünürlük taramalarında sentezlenen türevlerin yaygın organik çözücüler ve suda, 5AAU türevlerinden daha yüksek oranda çözündüğü belirlenmiştir. Sentezlenen moleküllerin her biri, alt yapısı kendi laboratuvarımızda oluşturulan yeni moleküllerdir. İleri aktivite çalışmalarına yön verecek çeşitlilikte sübstitüentlere sahip küçük ligandlardır. Bileşiklerin biyolojik aktivite çalışmaları devam etmektedir.
