Zekeriya Bıyıklıoğlu
Karadeniz Technical University
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Featured researches published by Zekeriya Bıyıklıoğlu.
Dyes and Pigments | 2008
Halit Kantekin; Zekeriya Bıyıklıoğlu
Abstract Novel, tetrasubstituted metal-free phthalocyanine and metallophtalocyanines bearing four 13-membered dithiadiaza macrocycle peripheral groups were synthesized by cyclotetramerization of the phthalonitrile derivative in a multi-step reaction sequence. The new compounds were characterized by a combination of IR, 1 H NMR, 13 C NMR, UV–vis, elemental analysis and MS spectral data.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy | 2012
Zekeriya Bıyıklıoğlu; Dilek Çakır
This paper describes the synthesis, spectroscopic characterization of a range of new axially-disubstituted silicon phthalocyanines with 2-[2-(dimethylamino)ethoxy] or 2-[2-(1,4,7,10,13-pentaoxa-16-azacyclooctadecan-16-yl)ethoxy] groups as axial ligands. 2-[2-(Dimethylamino)ethoxy]ethanol 2, 2-[2-(1,4,7,10,13-pentaoxa-16-azacyclooctadecan-16-yl)ethoxy]ethanol 4 are reacted with silicon phthalocyanine 1, to give an axially-disubstituted silicon phthalocyanines 3 and 5. Axially-disubstituted silicon phthalocyanine complexes were synthesized at the first time. Newly synthesized silicon phthalocyanines were characterized by UV-Vis, IR, (1)H NMR, (13)C NMR spectroscopy, ESI mass spectrometry. These new silicon(IV) phthalocyanines 3 and 5 showed excellent solubility in organic solvents such as CHCl(3), CH(2)Cl(2), acetone, DMF, DMSO, THF, EtOAc. The aggregation behavior of these compounds were investigated in different concentrations of DMSO. The effect of solvents on absorption spectra were studied in various organic solvents. The thermal stabilities of the silicon(IV) phthalocyanines 3 and 5 were determined by thermogravimetric analysis.
Journal of Photochemistry and Photobiology B-biology | 2016
Arzu Özel; Burak Barut; Ümit Demirbaş; Zekeriya Bıyıklıoğlu
The binding mode of water soluble peripherally tetra-substituted titanium(IV) phthalocyanine (Pc) compounds Pc1, Pc2 and Pc3 with calf thymus (CT) DNA was investigated by using UV-Vis spectroscopy and thermal denaturation studies in this work. The results of DNA binding constants (Kb) and the changes in the thermal denaturation profile of DNA with the addition of Pc compounds indicated that Pc1, Pc2 and Pc3 are able to bind to CT-DNA with different binding affinities. DNA photocleavage studies of Pc compounds were performed in the absence and presence of oxidizing agents such as hydrogen peroxide (H2O2), ascorbic acid (AA) and 2-mercaptoethanol (ME) using the agarose gel electrophoresis method at irradiation 650 nm. According to the results of electrophoresis studies, Pc1, Pc2 and Pc3 cleaved of supercoiled pBR322 DNA via photocleavage pathway. The Pc1, Pc2 and Pc3 compounds were examined for topoisomerase I inhibition by measuring the relaxation of supercoiled pBR322 DNA. The all of Pc compounds inhibited topoisomerase I at 20 μM concentration. A series of antioxidant assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, superoxide radical scavenging (SOD) assay and metal chelating effect assay were performed for Pc1, Pc2 and Pc3 compounds. The results of antioxidant assays indicated that Pc1, Pc2 and Pc3 compounds have remarkable superoxide radical scavenging activities, moderate 2,2-diphenyl-1-picrylhydrazyl activities and metal chelating effect activities. All the experimental studies showed that Pc1, Pc2 and Pc3 compounds bind to CT-DNA via minor groove binding, cleave of supercoiled pBR322 DNA via photocleavage pathway, inhibit topoisomerase I and have remarkable superoxide radical scavenging activities. Thanks to these properties the Pc1, Pc2 and Pc3 compounds are suitable agents for photo dynamic therapy.
Separation Science and Technology | 2007
Hakan Alp; Zekeriya Bıyıklıoğlu; Miraç Ocak; Ümmühan Ocak; Halit Kantekin; Gülsev Dilber
Abstract Two new macrocyclic ligands, containing nitrogen and sulfur donor atoms were designed and synthesized in a multi‐step reaction sequence. The macrocycles with amide group were used in solvent extraction of picrates of metals such as Ag+, Hg2+, Cd2+, Zn2+, Cu2+, Ni2+, Mn2+, Co2+ and Pb2+ from aqueous phase to the organic phase. The metal picrate extractions were investigated at 25±0.1°C by using UV‐visible spectrometry. The extractability and selectivity of the mentioned metal picrates were evaluated according to the organic solvents. The values of the extraction constants (log Kex) and the complex compositions were determined for the extracted complexes.
Journal of Coordination Chemistry | 2010
Hülya Karadeniz; İrfan Acar; Zekeriya Bıyıklıoğlu; Fatma Ağın; Halit Kantekin
The synthesis of octakis(4,5-bis{2-[2-(1-naphthyloxy)ethoxy]ethoxy}) metal-free (4) and metallophthalocyanines (5–8) were carried out by the cyclotetramerization of a 4,5-bis{2-[2-(1-naphthyloxy)ethoxy]ethoxy}phthalonitrile (3). Newly substituted octakisphthalocyanines showed enhanced solubility in organic solvents. The new compounds were characterized by IR, 1H-NMR, 13C-NMR, UV-Vis, and MS spectral data.
Journal of Inclusion Phenomena and Macrocyclic Chemistry | 2016
Ayşe Aktaş; İrfan Acar; Ece Tuğba Saka; Zekeriya Bıyıklıoğlu; Halit Kantekin
In this study, phthalocyanine complexes (Co and Fe) bearing (2-{2-[3-(trifluoromethyl)phenoxy]ethoxy}ethoxy) groups at peripheral position were synthesized using the phthalonitrile derivative and characterized by IR, 1H-NMR, UV–Vis and mass spectrometry. Catalytic activity of Co(II) and Fe(II) phthalocyanines were investigated in the oxidation of benzyl alcohol with different oxygen sources. Determination of the optimal conditions for oxidation of benzyl alcohol, the catalytic reactions were carried out change the reaction temperature, oxidant/cat ratio, types of oxidants and subst./catalyst ratio.
Journal of Inclusion Phenomena and Macrocyclic Chemistry | 2014
Volkan Çakır; Dilek Çakır; Zekeriya Bıyıklıoğlu; Halit Kantekin
In this study, a new phthalonitrile derivative 3 bearing 1,3-bis[3(dimethylamino)phenoxy]propan-2-ol 1, metal-free phthalocyanine (Pc) 4, metallophthalocyanines (MPcs) 5–7 and their quaternized derivatives 4a–7a were synthesized. Metal-free Pc 4 was prepared by cyclotetramerization of phthalonitrile derivate 3 and MPcs 5–7 were synthesized by heating 3 with NiCl2, CoCl2 and CuCl2 in n-pentanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, respectively. Quaternization of the dimethylamino functionality produced quaternized octacationic water soluble metal-free, Ni, Co and Cu Pcs which were soluble in water, DMF, DMSO. The aggregation behaviour of these compounds were investigated in different concentrations of chloroform for metal-free, Ni, Co and Cu Pcs. The effect of solvents on absorption spectra were studied in various organic solvents. The novel compounds were characterized using IR, 1H-, 13C NMR, UV–vis and MS spectral data.
Journal of Coordination Chemistry | 2017
Zekeriya Bıyıklıoğlu; Hakan Alp
Abstract In this study, 3-(4-{3-[3-(dimethylamino)phenoxy]propoxy}phenyl)propan-1-ol, 3-(4-{3-[3-(diethylamino)phenoxy]propoxy}phenyl)propan-1-ol and axially disubstituted silicon naphthalocyanines (SiNc) bearing electropolymerizable bis-[(4-{3-[3-(dimethylamino)phenoxy]propoxy}phenyl)propanoxy] and bis-[(4-{3-[3-(diethylamino)phenoxy]propoxy}phenyl)propanoxy] units were synthesized for the first time. Aggregation behavior of SiNcs was examined in different solvents and concentrations in DMSO. In all solvents and concentrations, SiNcs were non-aggregated. Also, electrochemical studies of SiNcs were investigated by cyclic and square wave voltammetry. While SiNcs gave only naphthalocyanine-based reduction process during the cathodic potential scans, they were electropolymerized on the working electrode during the anodic potential scan because of the oxidative electropolymerization of (4-{3-[3-(dimethylamino)phenoxy]propoxy}phenyl)propanoxy and (4-{3-[3-(diethylamino)phenoxy]propoxy}phenyl)propanoxy groups on the substituents of the complexes.
Journal of Biological Inorganic Chemistry | 2017
Meltem Göksel; Zekeriya Bıyıklıoğlu; Mahmut Durmuş
Two novel silicon(IV) phthalocyanines bearing 1,3-bis[3(dimethylamino)phenoxy]propan-2-ol or 1,3-bis[3(diethylamino)phenoxy]propan-2-ol groups at their axial positions were synthesized. These phthalocyanines were converted into their water soluble derivatives by the quaternization reaction with methyl iodide. The quaternized phthalocyanines show excellent solubility aqueous solutions without any aggregation which makes them potential photosensitizers for use in photodynamic therapy (PDT). For this reason, the photophysical and photochemical properties such as fluorescence quantum yields, lifetimes, singlet oxygen generation and photodegradation of both non-ionic (3 and 5) and quaternized cationic silicon(IV) phthalocyanines were investigated. Furthermore, the cytotoxicity of PDT was determined by colorimetric proliferation assay against to hepatocellular carcinoma (HuH-7) cancer cells. In this study, the cells were incubated with a novel water soluble silicon(IV) phthalocyanine derivatives and thereafter the cells were illuminated using broad-band incoherent light source.Graphical abstract
Journal of Coordination Chemistry | 2016
Zekeriya Bıyıklıoğlu; İpek Ömeroğlu; Hakan Alp
Abstract The new 2-[2-(6-tert-butyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol 1 and 2-[2-(6-pentyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol 2 have been synthesized. Axially disubstituted silicon phthalocyanines 3 and 4 have been synthesized by introducing 2-[2-(6-tert-butyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol and 2-[2-(6-pentyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol at the axial positions of silicon(IV) phthalocyanine, respectively. The electrochemical properties of silicon phthalocyanines 3 and 4 were also investigated by cyclic voltammetry (CV) and square wave voltammetry. Voltammetric studies show that while 3 showed two reversible reduction and one irreversible oxidation couples, 4 showed two quasi-reversible reduction and one irreversible oxidation couples.