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Öğe Coumarin bearing asymmetrical zinc(II) phthalocyanine functionalized SWCNT hybrid nanomaterial: Synthesis, characterization and investigation of bifunctional electrocatalyst behavior for water splitting(Elsevier B.V., 2021) Akyüz D.; Şenocak A.; Köksoy, BaybarsA novel asymmetrical zinc(II) phthalocyanine (Coum-Pc) bearing three 7-ethynyl-3-(3,4,5-trimethoxyphenyl) coumarin and one ethyloxy azido groups was synthesized and characterized for the first time. This novel asymmetric Coum-Pc was covalently attached to single walled carbon nanotube (SWCNT) containing terminal ethynyl groups via the azide-alkyne Huisgen cycloaddition (Click) reaction for preparation of coumarin bearing zinc(II) phthalocyanine functionalized SWCNT hybrid nanomaterial (SWCNT-Coum-Pc). Hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalyst for water splitting behavior of SWCNT-Coum-Pc hybrid nanomaterial were evaluated. The SWCNT-Coum-Pc hybrid reduced the onset potential required for HER by approximately 200 mV compared to SWCNT catalyst in acidic medium. The SWCNT-Coum-Pc catalyst reduced the HER overpotential of 570 mV at a current density of 10 mA cm−2 in alkaline medium. It also exhibited outstanding activity in OER, required only an overpotential of 330 mV at a current density of 10 mA cm−2. Heterogeneous rate constants of the electrodes from impedance analysis were used to calculate the value of charge transfer resistance and the conductivity of the composite film. The presence of Coum-Pc groups on the SWCNT surface increased for both the conductivity and electron transfer rate of the SWCNT. Therefore, SWCNT-Coum-Pc hybrid significantly improved the performance of OER and HER for water splitting. The present work provided a promising ground for the of SWCNT-Coum-Pc hybrid as a bifunctional electrocatalyst for water splitting.Öğe Design and in silico study of the novel coumarin derivatives against SARS-CoV-2 main enzymes(Taylor & Francis Inc, 2022) Ozdemir, Mucahit; Köksoy, Baybars; Ceyhan, Deniz; Sayin, Koray; Ercag, Erol; Bulut, MustafaThe novel coronavirus (SARS-CoV-2) causes severe acute respiratory syndrome and can be fatal. In particular, antiviral drugs that are currently available to treat infection in the respiratory tract have been experienced, but there is a need for new antiviral drugs that are targeted and inhibit coronavirus. The antiviral properties of organic compounds found in nature, especially coumarins, are known and widely studied. Coumarins, which are also metabolites in many medicinal drugs, should be investigated as inhibitors against coronavirus due to their pharmacophore properties (low toxicity and high pharmacokinetic properties). The easy addition of substituents to the chemical structures of coumarins makes these structures unique for the drug design. This study focuses on factors that increase the molecular binding and antiviral properties of coumarins. Molecular docking studies have been carried out to five different proteins (Spike S1-subunit, NSP5, NSP12, NSP15, and NSP16) of the SARS-CoV-2 and two proteins (ACE2 and VKORC1) of human. The best binding scores for 17 coumarins were determined for NSP12 (NonStructural Protein-12). The highest score (-10.01 kcal/mol) in the coumarin group is 2-morpholinoethan-1-amine substituted coumarin. Molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) analyses of selected ligand-protein complexes were performed. The binding energies in each 5 ns were calculated and it was found that the interaction between ligand and target protein were stable. Communicated by Ramaswamy H. SarmaÖğe In silico study and structure-activity relations of glucose-bound coumarin derivatives against the NSP12 protein of SARS-CoV-2(Atatürk Üniversitesi, 2021) Çelik, Esra; Özdemir, Mücahit; Yalçın, Bahattin; Köksoy, BaybarsIn this study, designs of antiviral drug candidates that may be effective against SARS-CoV-2 virus were performed. Molecular docking was used to explore the effect of coumarin and its derivatives, which have antiviral action, on RNA polymerase NSP12, one of the key proteins of the coronavirus. The sugar group on coumarins was selected to increase hydrophilicity, and the amide groups were diversified to investigate selectivity. Coumarins containing 3-(p-phenylamidomorpholine), 3-(p-phenylamidopiperazine), and 3-(p-phenylamidopiperidine) groups had the best docking scores, with binding affinities of -10.1 kcal/mol, -10.1 kcal/mol, and -10.0 kcal/mol, respectively. The pharmacokinetic and toxicokinetic properties of compounds were estimated close to reality using various databases, and their values were close to the target values needed for a compound to become a drug. This study is also thought to give insight to scientists working for the design of SARS-CoV-2 antiviral drugs in terms of the structure activity relationship between coumarin and its functional groups.Öğe In silico, 6lu7 protein inhibition using dihydroxy-3-phenyl coumarin derivatives for SARS-CoV-2(Turkish Chemical Society, 2020) Özdemir, M.; Köksoy, Baybars; Ceyhan, D.; Bulut, M.; Yalçın, B.The new emerging coronavirus (SARS-CoV-2) has become a global health problem with very rapid transmission from person to person, causing severe acute respiratory problems. In the circumstance, the discovery of vaccines or drugs to eradicate or reduce the impact of the COVID-19 has made it imperative to develop new approaches. In the current situation, many drugs on the drug bank have been researched computationally, and there has not been an emphasis on synthetic effort. We tested 42 coumarin derivatives (1a-14c) containing 14 different substituents, which are secondary metabolites of plants, and the anticoagulant Coumadin (warfarin) drug as a reference by Molecular Docking calculation technique on 6LU7 main protease of the coronavirus. Optimized geometries, electron motions and energy values of all coumarins were also determined using the Density Functional Theory (DFT) method. The drug properties of coumarins were estimated using the ADME-Tox test method. Coumarins formed strong interactions with HIS41, CYS145, and other amino acids in the active site of the main protease. In general, 6,7-dihydroxy-3-phenylcoumarin derivatives gave relatively higher scores, and for all coumarins, biphenyl (for 10a,-8.6 kcal/mol; 10b,-8.3 kcal/mol; 10c,-7.9 kcal/mol) and 4-trifluoromethylphenyl (for 13a,-8.1 kcal/mol; 13b,-8.1 kcal/mol; 13c-8.3 kcal/mol) substituted coumarin had the highest score. The coumarins data reported in this study serves as a stepping stone for in vitro and in vivo experimental research for vaccine development purposes. © 2020, Turkish Chemical Society. All rights reserved.Öğe Novel lanthanide metallophthalocyanines bearing iodine group and their singlet oxygen generation ability(Turkish Chemical Society, 2022) Köksoy, BaybarsIn this study, five novel mono rare earth metallo phthalocyanine derivatives (1a-e) were synthesized by cyclotetramerization of 4-iodophthalonitrile and corresponding metal salts. These novel compounds were characterized by IR, elemental analyses, UV–vis, and MALDI-TOF spectral data. Moreover, the ability of singlet oxygen generation and aggregation behaviour of these phthaloyanines were investigated in dimethyl sulfoxide using UV-Vis spectroscopy. Gadolinium metallo phthalocyanine has the best singlet oxygen quantum yield and it can be a potential candidate for the photodynamic therapy (PDT) of cancer.Öğe Novel lutetium(III) phthalocyanine-coumarin dyads; synthesis, characterization, photochemical, theoretical and antioxidant properties(Elsevier S.A., 2020) Özdemir, M.; Köksoy, Baybars; Yalçın, B.; Taşkın, T.; Selçuki, N.A.; Salan, Ü.; Durmuş, M.In this study, novel 7-oxy-3-ethyl-6-hexyl-4-methylcoumarin substituted lutetium(III) phthalocyanine compounds were synthesized, characterized and their photochemical, theoretical, and antioxidant properties were examined. All complexes were characterized by common spectroscopic methods such as FT-IR, UV–vis, 1H NMR, MALDI-TOF-MS and elemental analysis as well. Geometry optimization of phthalocyanine compounds was calculated in the B3LYP functional using 6-31G (d, p) + SDD basis set of the Density Functional Theory. Aggregation, singlet oxygen generation, and photodegradation behavior under light irradiation of the complexes (1–4) were investigated in dimethylformamide. The three phthalocyanine compounds (1, 2, and 4) showed a high level of singlet oxygen efficiency were compared with the unsubstituted zinc(II) and lutetium(III) phthalocyanine compounds because their quantum yield values were found to be over 0.80. The radical cation scavenging activities of the compounds 3 (120.344 mM trolox/mg) and 4 (188.733 mM trolox/mg) are quite remarkable in 2,2?-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid analysis according to butylated hydroxyanisole (52.63 mM trolox/mg). © 2020 Elsevier B.V.Öğe Novel SWCNT-hybrid nanomaterial functionalized with subphthalocyanine substituted asymmetrical zinc (II) phthalocyanine conjugate: Design, synthesis, characterization and sensor properties for pesticides(Elsevier Science Sa, 2021) Köksoy, Baybars; Akyuz, Duygu; Senocak, Ahmet; Durmus, Mahmut; Demirbas, ErhanThe novel asymmetric zinc (II) phthalocyanines containing one ethyloxy azido and three iodine (Iodo-Pc) or subphthalocyanine (SubPc-Pc) groups were designed and synthesized for the first time. These novel phthalocyanines were chemically characterized by common spectral methods such as FT-IR, UV-vis, H-1-NMR,C- 13-NMR and MALDI-TOF mass spectroscopy and elemental analyses as well. Furthermore, a novel hybrid carbon nanomaterial (SWCNT-SubPc-Pc) bearing subphthalocyanine substituted zinc (II) phthalocyanine conjugate on the single walled carbon nanotube (SWCNT) surface was also prepared via azide-alkyne Huisgen cycloaddition (click) reaction. This novel hybrid carbon nanomaterial was chemically characterized by UV-vis, FT-IR and Raman spectroscopies. The thermal behaviour of the prepared SWCNT-SubPc-Pc was characterized by thermogravimetric analysis. Surface morphologies of the hybrid material were also investigated by scanning and transmission electron microscopies. SWCNT-SubPc-Pc hybrid nanomaterial was successfully modified on glassy carbon electrode (GCE) by using drop cast method. Then, the GCE/SWCNT-SubPc-Pc electrode was tested as pesticide sensor via electrochemical methods. The electrochemical responses were recorded using differential pulse (DPV) and cyclic voltammetries. The modified electrode acted as selectively to methyl parathion among the used pesticides (methyl parathion, acetamiprid and chlorantraniliprole). The electrochemical sensor behaviour exhibited a broad linear range (2.5 nM and 3.75 x 10(-8) M) and low detection limit (1.78 nM) for methyl parathion. Moreover, high performance liquid chromatography was used to validate the results obtained from orange and cherry juice samples with respect to the DPV results.Öğe Sensitive, simple and fast voltammetric determination of pesticides in juice samples by novel BODIPY-phthalocyanine-SWCNT hybrid platform(Pergamon-Elsevier Science Ltd, 2021) Köksoy, Baybars; Akyuz, Duygu; Senocak, Ahmet; Durmus, Mahmut; Demirbas, ErhanThe present work describes the first synthesis of novel asymmetric zinc (II) phthalocyanine (ZnPc) including three boron dipyrromethene (BODIPY) and one ethyloxy azido moieties. Moreover, single walled carbon nanotube (SWCNT) surface was functionalized by this ZnPc containing BODIPY; using the azide-alkyne Huisgen cycloaddition (Click) reaction to obtain SWCNT-ZnPc hybrid material. Structural, thermal and morphological characterizations of both ZnPc and SWCNT-ZnPc hybrid were carried out in-depth by spectroscopic, thermal and microscopic techniques. In this study, the synthesized SWCNT-ZnPc material was decorated on composite glassy carbon electrode (GCE) by means of an easy and a practical drop cast method. The modified electrode was tested as a non-enzymatic electrochemical sensor in various common pesticides such as methyl parathion, deltamethrin, chlorpyrifos and spinosad. Electrochemical behavior of non-enzymatic electrode (GCE/SWCNT-ZnPc) was determined via cyclic voltammetry and differential pulse voltammetry. The non-enzymatic sensor demonstrated high selectivity for methyl parathion in a wide linear range (2.45 nM-4.0 x 10(-8) M), low limit of detection value (1.49 nM) and high sensitivity (0.1847 mu A nM(-1)). Also, the developing non-enzymatic sensor exhibited good repeatability (RSD = 2.3% for 10 electrodes) and stability (85.30% for 30 days). Validation guidelines by HPLC and statistical analysis showed that the proposed voltammetric method were precise, accurate, sensitive, and can be used for the routine quality control of methyl parathion determination in juice samples.Öğe Symmetrical and Asymmetrical Thiophene-Coumarin-Based Organic Semiconductors(American Chemical Society, 2023) Altınışık, Sinem; Özdemir, Mücahit; Kortun, Arzu; Zorlu, Yunus; Yalçın, Bahattin; Köksoy, Baybars; Koyuncu, SermetOrganic semiconductors are a valuable material class for optoelectronic applications due to their electronic and optical properties. Four new symmetric and asymmetric thiophene-coumarin derivatives were designed and synthesized via Pd-catalyzed Suzuki and Stille Cross-Coupling reactions. Single crystals of all synthesized thiophene-coumarin derivatives were obtained, and π···π interactions were observed among them. The π···π interactions were supported by UV-vis, transmission electron microscopy, and atomic force microscopy analyses. The photophysical and electrochemical properties of the coumarins were investigated and supported by density functional theory studies. Fluorescence quantum yields were recorded between 36 and 66%. Moreover, mega Stokes shifts (175 nm or 8920 cm) were observed in these new chromophore dyes. The emission and absorption colors of the thiophene-coumarin compounds differed between their solution and film forms. Electrochemically, the highest occupied molecular orbital levels of the coumarins increased with the 3,4-ethylenedioxythiophene group, leading to a narrowing of the band gap, while the phenyl bridge weakened the donor-acceptor interaction, expanding the band gap.Öğe Synthesis and photovoltaic properties of novel ferrocene-substituted metallophthalocyanines(Royal Society of Chemistry, 2021) Özdemir, Mücahit; Köksoy, Baybars; Kuruca, Halid; Altindal, Ahmet; Durmus, Mahmut; Koyuncu, Sermet; Yalcin, Bahattin; Bulut, MustafaIn this paper, a series of new metallophthalocyanines, including ferrocene groups, were designed, synthesized and, characterized, and their photovoltaic properties were investigated as alternative electron-donor materials in bulk heterojunction (BHJ) solar cells. These products were synthesized by a Sonogashira cross-coupling reaction between tetraiodophthalocyanine and ethynyl ferrocene. The newly synthesized phthalocyanines (4-6) were characterized by FT-IR, UV-Vis, H-1 NMR, and MALDI-TOF spectroscopic methods and elemental analysis. The electrochemical characterizations were carried out by cyclic voltammetry as well as differential pulse voltammetry. Density functional theory calculations were realized to prove the charge separation between ferrocene as an electron-donor and the phthalocyanine ring as an acceptor. According to UV-Vis measurements, a 25 nm red-shift was observed for complex 4 compared with complexes 5 and 6. Finally, the photovoltaic performance of these compounds used as an electron-donor moiety in a BHJ device were investigated. A function of different blend ratios was tested by fabricating a series of BHJ devices with the architecture of FTO/PEDOT:PSS/4-6: PCBM blend/Ag with an identical thickness of the active layer. The results indicated that the photovoltaic conversion efficiency of BHJ devices exhibited a strong blend-ratio dependence. The maximum power conversion efficiency was obtained by 5-based devices, as 3.65%, with a blend ratio of 1.5 : 1.0 under standard AM 1.5 illumination.Öğe The Role of Electron-Donating Subunits in Cross-Linked BODIPY Polymer Films(John Wiley and Sons Inc, 2024) Özdemir, Mücahit; Köksoy, Baybars; Yalcin, B.; Koyuncu, SermetA new method for synthesizing cross-linked 4,4-difluoro-4-bora-3a,4a-diaza-s-indacenes (BODIPYs) using a radical-based thiol-ene click reaction is developed. This method is simple, efficient, and cost-effective, and it produces polymers with unique optical, electrochemical, and surface morphology properties. Significant blue shifts in absorption and photoinduced electron transfer in emissions are observed in the cross-linked BODIPY thin films. Cross-linking also leads to the restriction of conjugation, which results in the breakage of the terminal vinyl group, an increase in the oxidation potential, and a slight upshift in the HOMO position. As a result, the electrochemical band gap is widened from 1.88 to 1.94 eV for polymer bearing N,N-dimethylamino-BODIPY and from 1.97 to 2.02 eV for polymer bearing N,N-diphenylamino-BODIPY moieties. Monomer thin films form planar surfaces due to crystallinity, while amorphous cross-linked BODIPY polymers form more rough surfaces. Additionally, photopatterning on the film surface is successfully performed using different patterned masks. This new method for synthesizing cross-linked BODIPYs has the potential to be used in a variety of applications, including organic electronics, bioimaging, and photocatalysis. © 2023 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH.
