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    Metal or metal-free phthalocyanines containing morpholine substituents: synthesis, spectroscopic and photophysicochemical properties
    (Taylor & Francis Ltd, 2022) Demirbas, Umit; Piskin, Mehmet; Durmus, Mahmut; Kantekin, Halit
    The phthalonitrile (3) and its peripherally tetra 4-(3-morpholinophenoxy) substituted metal-free (4), lead(II) (5) and zinc(II) (6) phthalocyanine derivatives were synthesized. The structures of 3-6 were confirmed by FT-IR, H-1-NMR, MALDI-TOF mass, UV-vis and fluorescence spectral data. The solubility and aggregation behaviors of 4-6 were determined in dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), tetrahydrofuran (THF), chloroform (CHCl3) and dichloromethane (CH2Cl2). The observed sharp absorptions were evidence of formation of non-aggregated phthalocyanine species at the studied concentration. The effects of the substituent and central metal ions (metal-free, zinc or lead) on spectroscopic and photophysicochemical properties were determined. Their photophysicochemical properties such as fluorescence quantum yields and lifetimes, singlet oxygen generation and photodegradation quantum yields were investigated in DMSO. The fluorescence spectra of metal-free (4) and lead(II) (5) phthalocyanines were not recorded due to negligible fluorescence emissions of these phthalocyanines. The zinc(II) phthalocyanine (6) had 0.17 fluorescence quantum yield (phi(F)) and 1.42 fluorescence lifetime (tau(F)). The phthalocyanines (4-6) had 0.18, 0.41, 0.52 singlet oxygen quantum yields (phi(Delta)) and 0.51, 3.90, 0.46 photodegradation quantum yields (phi(Delta)), respectively. The zinc(II) phthalocyanine (6) in particular could be a potential Type II photosensitizer candidate for photodynamic therapy in cancer treatment.
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    Öğe
    Metal-free, zinc(II) and lead(II) phthalocyanines functioning with 3-(2H-benzo[d][1,2,3]triazol-2-yl)-4-hydroxyphenethyl methacrylate groups: Synthesis and investigation of photophysical and photochemical properties
    (Elsevier Science Sa, 2016) Demirbas, Umit; Piskin, Mehmet; Barut, Burak; Bayrak, Riza; Durmus, Mahmut; Kantekin, Halit
    In this study, the synthesis and characterization of 3-(2H-benzo[d][1,2,3]triazol-2-yl)-4-hydroxyphenethyl methacrylate substituted novel phthalonitrile compound and its peripherally substituted zinc(II) lead(II) and metal-free phthalocyanine derivatives were performed for the first time. This novel compounds were characterized by obtained data from general spectroscopic methods such as FT-IR, H-1 NMR, C-13 NMR and mass. The photophysical and photochemical properties of these phthalocyanines were investigated in N,N-dimethylformamide solutions for determination of their photosensitizing abilities in photocatalytic applications such as photodynamic therapy. The lead(II) phthalocyanine complex did not produce any fluorescent in N,N-dimethylformamide because of the heavy atom effect of bigger lead atom. The fluorescence quantum yields of studied zinc(II) and metal-free phthalocyanines were found to quite higher than unsubstituted zinc(II) phthalocyanine due to substitution of the phthalocyanine skeleton. The influence of substituent and variety of the central metal ions on spectroscopic, photophysical and photochemical properties were also determined and compared. (C) 2016 Elsevier B.V. All rights reserved.
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    Öğe
    New peripherally and non-peripherally tetra-substituted metal-free, magnesium(II) and zinc(II) phthalocyanine derivatives fused chalcone units: Design, synthesis, spectroscopic characterization, photochemistry and photophysics
    (Elsevier Science Sa, 2018) Kantekin, Halit; Yalazan, Halise; Kahriman, Nuran; Ertem, Beytullah; Serdaroglu, Vildan; Piskin, Mehmet; Durmus, Mahmut
    Chalcone containing new peripherally and non-peripherally tetra-substituted metal-free and metallophthalo-cyanine derivatives were designed and synthesized (Schemes 1 and 2). The structures of chalcone-phthalocyanines were characterized by a combination of common spectroscopic techniques such as LC-MS/MS (for new phthalonitrile derivative 3a), ground state electronic absorption spectra (for all new phthalocyanines), H-1 NMR spectroscopy (for all new compounds), C-13 NMR spectroscopy (for new phthalonitrile and metal-free phthalocyanine derivatives), Fourier transform infrared (FT-IR with ATR sampling accessory) (for all new compounds) and MALDI-TOF mass spectral data (for all new phthalocyanines and new phthalonitrile derivative 3b) as well as elemental analysis. In addition, the effects of the presence of different kinds of metal ions [magnesium(II) or zinc (II)] in the phthalocyanine core and the effects of the introduction of (3,4-dimethoxyphenyl)-3-oxoprop-1en-1-yl)phenoxy units at both peripheral and non-peripheral positions of the phthalocyanine skeleton on photophysical and photochemical properties of the new substituted magnesium(II) and zinc(II) phthalocyanines have also been examined in DMF. The obtained results were compared with each other and with unsubstituted magnesium(II) and zinc(II) phthalocyanines. All newly synthesized phthalocyanines are soluble in common organic solvents as well as no type of aggregation was observed in these solvents. Moreover; the chalcone fused magnesium(II) and zinc(II) phthalocyanines also showed excellent fluorescence properties. Specifically, the new non-peripheral zinc(II) and magnesium(II) chalcone-phthalocyanines have the remarkable potential to be used as Type II photosensitizers for the treatment of cancer in PDT owing to their good singlet oxygen and appropriate photodegradation quantum yields. Since chalcones and their derivatives show a broad range of biological and pharmaceutical activities, these products are promising candidates for various applications, particularly as photosensitizers for photodynamic therapy in combination with fluorescence imaging.
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    Synthesis, characterisation, photophysical and photochemical properties of free-base tetra-(5-chloro-2-(2,4-dichlorophenoxy) phenoxy)phthalocyanine and respective zinc(II) and lead(II) complexes
    (Elsevier Science Sa, 2017) Demirbas, Umit; Piskin, Mehmet; Akcay, Hakki Turker; Barut, Burak; Durmus, Mahmut; Kantekin, Halit
    In this study, novel peripherally tetra-(5-chloro-2-(2,4-dichlorophenoxy)phenol) substituted metal-free (4), zinc(II) (5) and lead(II) (6) phthalocyanine derivatives were synthesised. The novel phthalocyanines (4-6) were characterised by general spectroscopic methods such as IR, H-1 NMR, UV-vis, mass spectrometry and elemental analysis. Once the solubilities of the compounds were investigated, it was noticed that they have excellent solubility and did not tend to aggregation behaviour in common solvents. The photophysical and photochemical properties of novel phthalocyanines (4-6) were investigated in dimethysulfoxide. The effects of substituted 5-chloro-2-(2,4-dichlorophenoxy)phenoxy group and central metal ion [zinc(II)/lead(II)] on photophysical and photochemical properties of the novel phthalocyanines have also been examined, and the results were compared with unsubstituted zinc (II) phthalocyanine. According to photophysical and photochemical investigation results, it was observed that the novel phthalocyanines (4-6) have a potential for PDT application. (C) 2016 Elsevier B.V. All rights reserved.
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    Öğe
    The determination of photophysical and photochemical parameters of novel metal-free, zinc(II) and lead(II) phthalocyanines bearing 1,2,4-triazole groups
    (Elsevier Science Sa, 2016) Demirbas, Umit; Piskin, Mehmet; Bayrak, Riza; Unluer, Dilek; Dugdu, Esra; Durmus, Mahmut; Kantekin, Halit
    In this study the synthesis and characterization of novel phthalonitrile compound (3) and its metal-free (4), zinc(II) (5), and lead(II) (6) phthalocyanines bearing four 4-(4-methoxyphenylethyl)-5-propyl-2,4-dihydro-3H-1,2,4-triazol-3-one groups at peripheral positions were synthesized for the first time. These novel compounds were fully characterized by FT-FT-IR, H-1 NMR, UV-vis and MALDI-TOF mass spectroscopic techniques. Their photochemical and photophysical properties were also investigated in N, N-dimethylformamide solutions. In addition, the effect of 4(4-methoxyphenylethyl)-5-propyl-2,4dihydro-3H-1,2,4-triazol-3-one groups as substituents and central metal ions (without metal, zinc(II) or lead(II)) in the phthalocyanine cavity on these properties were also compared. The studied zinc(II) or lead (II) phthalocyanines can be potential Type II photosensitizers for photodynamic therapy in cancer applications because these phthalocyanines showed good singlet oxygen generation and appropriate photodegradation. (C) 2016 Elsevier B.V. All rights reserved.
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    Zinc(II) and lead(II) phthalocyanines bearing thiadiazole substituents: Synthesis, characterization, photophysical and photochemical properties
    (Elsevier, 2019) Demirbas, Umit; Piskin, Mehmet; Bayrak, Riza; Durmus, Mahmut; Kantekin, Halit
    In this study; phthalonitrile compounds 4-((5-methyl-1,3,4-thiadiazol-2-yl)thio)phthalonitrile (4) and 3-((5-methyl-1,3,4-thiadiazol-2-yl)thio)phthalonitrile (5) were synthesized. These compounds were converted to their respective peripherally and non-peripherally tetra-substituted zinc(II) (6 and 7) and lead(II) (8 and 9) phthalocyanine derivatives. The novel phthalocyanine complexes were characterized by using different spectroscopic techniques including FT-IR, UV-Vis, H-1 NMR and mass. The spectroscopic, photochemical and photophysical properties of the phthalocyanines were investigated for determination of their potential as photosensitizers for photodynamic therapy. In addition, the effects of the substituent, binding position and the variety of central metal ions in phthalocyanine core on photochemical and photophysical properties were determined. (C) 2019 Elsevier B.V. All rights reserved.