Person: SALAN, ÜMİT
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SALAN
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ÜMİT
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Publication Metadata only Synthesis, characterization, and electrochemical and in-situ spectroelectrochemical properties of novel peripherally and non-peripherally 7-oxy-3-(3,4-dimethoxyphenyl) coumarin substituted phthalocyanines(ELSEVIER SCI LTD, 2019) ÖZKAYA, ALİ RIZA; Feridun, Seda Gureli; Orman, Efe Baturhan; Salan, Umit; Ozkaya, Ali Riza; Bulut, MustafaNovel metal-free (4 and 9), Zn(II) (5 and 10) and Co(II) (6 and 11) phthalocyanines (Pcs) bearing four 7-oxy-3(3,4-dimethoxyphenyl)coumarin (1) substituents at peripheral (13) and non-peripheral (a) positions have been prepared by cyclotetramerization reactions of 4-(3-(3,4-dimethoxyphenyl)coumarin-7-oxy)phthalonitrile (3) or 3-(3-(3,4-dimethoxy-phenyl)coumarin-7-oxy)phthalonitrile (8), respectively, in the presence of relevant metal acetate salts in N,N-dimethylaminoethanol. The compounds have been characterized by elemental analysis, FTIR, UV-Vis and MALDI-TOF mass spectroscopies. Thermal properties of the compounds were evaluated by thermogravimetric analysis and differential scanning calorimetry. Electrochemical redox properties of all compounds were investigated by voltammetric and in-situ spectroelectrochemical measurements in dimethylsulfoxide including tetrabutyl ammonium perchlorate as the supporting electrolyte. The metal-free and Zn(II)Pc compounds displayed Pc ring-based redox processes whereas both Pc ring-based and metal-based electron transfer processes were observed for Co(II)Pc complexes. H-aggregation tendency of peripherally substituted compounds was found to be much higher than that of non-peripherally substituted ones. It was observed that there have been systemmatic redox potential and aggregation behaviour differences between the peripherally and non-peripherally substituted Pc compounds. These differences were attributed to different sterical and conformational effects of these substitution patterns. In-situ spectroelectrochemical and in-situ electrocolorimetric measurements suggested that peripherally substituted Co(II)Pc is a multi-coloured chromophore material displaying distinct spectral and colour changes during the first reduction and oxidation processes, and thus, being suitable for electrochromic applications.Publication Metadata only The synthesis and fluorescence properties of novel chromenone-crown ethers(TAYLOR & FRANCIS LTD, 2010) SALAN, ÜMİT; Gunduz, Cihan; Salan, Uemit; Bulut, Mustafao-Dihyroxy-3-phenylchromenone derivatives, namely, 6,7-dihydroxy-3-(3',4'-dimethoxyphenyl)chromenone and 6,7-dimethoxy-3-(3',4'-dihydroxyphenyl)chromenone, were obtained from 2,4,5-trihydroxybenzaldehyde/3,4-dimethoxyphenylacetic acid and 2-hydroxy-4,5-dimethoxybenzaldehyde/3,4-dihydroxyphenylacetic acid, respectively, in the presence of acetic anhydride and sodium acetate under an inert atmosphere, after treatment with MeOH/HCl(aq). The chromenone-crown ethers were prepared from cyclic condensation of o-dihydroxy-3-phenylchromenones with poly(ethylene glycol) ditosylates in the presence of CH3CN/alkali metal carbonates. The chromatographically purified novel chromenone-crown ethers were identified by 1H NMR, MALDI-TOF mass spectrometry and elemental analysis. The fluorescence and UV-vis spectroscopic properties of the obtained chromenone-crown ethers and their complexes with Li+, Na+ and K+ perchlorate salts were estimated in acetonitrile. The quantum yields of novel chromenone-crown ethers were determined by the comparative method. [image omitted].Publication Metadata only Synthesis and characterization of novel 7-oxy-3-ethyl-6-hexyl-4-methylcoumarin substituted metallo phthalocyanines and investigation of their photophysical and photochemical properties(ROYAL SOC CHEMISTRY, 2019) YALÇIN, BAHATTİN; Ozdemir, Mucahit; Karapinar, Begumhan; Yalcin, Bahattin; Salan, Umit; Durmus, Mahmut; Bulut, MustafaIn this study, the synthesis of novel 7-hydroxy-3-ethyl-6-hexyl-4-methylcoumarin (1), four respective phthalonitriles; 4-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (2), 3-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (3), 4-chloro-5-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (4), and 4,5-bis(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (5) and their corresponding alpha tetra, beta tetra and beta octa 7-oxy-3-ethyl-6-hexyl-4-methylcoumarin and beta octa 4-chloro-5-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin) substituted Zn(ii) (6a-9a) and In(iii) Cl (6b-9b) phthalocyanines has been performed. The novel purified compounds were characterized by standard characterization techniques such as elemental analysis, thermal analysis, FT-IR, UV-vis, H-1-NMR and MALDI-TOF mass spectrometry. All of the obtained phthalocyanines showed lipophilic behaviour with excellent solubility in organic solvents such as acetone, dichloromethane, chloroform, pyridine and ethyl acetate. The fluorescence quenching behaviour was investigated using 1,4-benzoquinone and potassium iodide as quenchers. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties of these novel phthalocyanines (6a-9a and 6b-9b) were studied in DMF. They produced high singlet oxygen (for example phi(Delta) = 0.99 for 7b) and showed appropriate photodegradation (in the order of 10(-5)) which is very important for photodynamic therapy (PDT), and thus these phthalocyanines can be used as Type II photosensitizers in PDT applications.Publication Metadata only Synthesis, characterization and electrochemical properties of tetra 7-oxy-3-biphenylcoumarin substituted metal-free, zinc(II), cobalt(II) and indium(III) phthalocyanines(ELSEVIER SCI LTD, 2016) ÖZKAYA, ALİ RIZA; Gok, Asiye; Orman, Efe Baturhan; Salan, Umit; Ozkaya, Ali Riza; Bulut, MustafaA novel coumarin, 7-hydroxy-3-biphenylcoumarin 1, was prepared by Perkin reaction of 4-biphenylacetic acid with 2,4-dihydroxybenzaldehyde in the presence of NaOAc/Ac2O. In addition, two respective phthalonitril derivatives, 7-(2,3-dicyanophenoxy)-3-biphenylcoumarin 2/7-(3,4-dicyanophenoxy)-3-biphenylcoumarin 3, were synthesized by nucleophilic aromatic substitution reactions of 3-nitro/4-nitrophthalonitrile with 7-hydroxy-3-biphenylcoumarin 1. The synthesis of corresponding novel zinc(II) phthalocyanines (Pcs) 4 and 8, cobalt(II) Pcs 5 and 9, indium(III)(Cl) Pcs 6 and 10, and metal-free Pcs 7 and 11, carrying 7-oxy-3-biphenylcoumarins in the non-periphery/periphery was performed by cyclotetramerization of compounds 2 or 3. The novel chromogenic coumarin 1, phthalonitriles (2 and 3) and Pcs (4-11) were characterized by elemental and spectroscopic analysis, including H-1 NMR, FT-IR, UV-vis spectral and MALDI-TOF mass data. The redox properties of these compounds were also investigated by voltammetry and in situ spectroelectrochemistry on Pt in dimethylsulfoxide/tetrabutylammonium perchlorate. Furthermore, the electrocatalytic performances of the compounds for the oxygen reduction reaction were also studied. (C) 2016 Elsevier Ltd. All rights reserved.Publication Metadata only EVALUATION OF ANTIOXIDANT, RADICAL-SCAVENGING AND ACETYLCHOLINESTERASE INHIBITORY ACTIVITIES OF VARIOUS CULINARY HERBS CULTIVATED IN SOUTHERN TURKEY(WILEY, 2014) OGAN, AYŞE; Danis, Ozkan; Yuce-Dursun, Basak; Cimen, Talin; Demir, Serap; Salan, Umit; Yalcin, Guler; Ogan, AyseThe purpose of this study was to determine the antioxidant, radical-scavenging, and acetylcholinesterase inhibitory capabilities of water and methanol extracts of Rhus coriariaL., Ocimum basilicumL., Rosmarinus officinalisL., Salvia officinalisL. and Thymbra spicataL., which are grown in the Hatay province of Turkey. Total antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (22-782.6g/mL EC50),OH scavenging (3.93-33.43g/mL EC50), ferric (0.143-3.083mmol trolox equivalent (TE)/g), and cupric-reducing antioxidant power (0.143-3.083mmol TE/g) assays. The phenolic composition of the methanolic extract of R.coriaria leaves was also investigated, and the active compound was identified as 4-O-methylgallic acid. The highest IC50 value of acetylcholinesterase inhibitory activity (1.170.04mg/mL) was observed in R.coriaria leaves. Principal component analysis showed that R.coriaria leaves possessed greater antioxidant and anti-acetylcholinesterase potential as compared with the other evaluated plants. Practical ApplicationsAntioxidants are widely used in the food industry to prevent the formation of toxic oxidation products and prolong shelf life. Because of increasing concern among consumers about the use of synthetic antioxidants, there has been a great interest in the identification and use of natural antioxidants. The present study reveals that Rhus coriaria leaves, which are not commonly used in Mediterranean cuisine, are a promising source of natural antioxidants and could be considered as a potential source of anti-acetylcholinesterase agents and food preservatives. Both the antioxidant and anti-acetylcholinesterase effects of R.coriaria leaves may be beneficial in the treatment of Alzheimer's disease.Publication Metadata only Photovoltaic and electrocatalytic properties of novel ball-type phthalocyanines bridged with four dicumarol(ROYAL SOC CHEMISTRY, 2012) ÖZKAYA, ALİ RIZA; Salan, Umit; Altindal, Ahmet; Ozkaya, Ali Riza; Salih, Bekir; Bekaroglu, OzerThe new ball-type metallo bisphthalocyanines (Co2Pc2 and Zn2Pc2) were synthesized from the corresponding [4,4'-bis(dicoumaroylphthalonitrile)] which can be obtained from the reaction of 3,3'-methylenebis(4-hydroxy-2H-chromen-2-one) and 4-nitrophthalonitrile. The structures of the newly synthesized compounds have been confirmed and characterized by elemental analysis, UV/Vis, IR and H-1 NMR spectroscopies and MALDI-TOF mass spectrometry. Solar cells of the configuration ITO/Co2Pc2/C60/Al and ITO/Zn2Pc2/C60/Al were fabricated. The effect of the thickness of the active Pc layer - the thickness of the Pc layer was varied from 15 to 80 nm - on solar cells parameters has been investigated. A nearly thickness independent open circuit voltage was observed in both structures. The maximum photovoltaic conversion efficiency, short circuit current and fill factor were observed in ITO/Zn2Pc2/C60/Al cell with 80 nm Pc layer to be 0.255%, 1 mA cm(-2) and 0.38, respectively. The redox properties of the ball-type complexes were investigated by cyclic voltammetry, controlled-potential coulometry and in situ spectroelectrochemistry in DMSO-TBAP. The electrochemical measurements showed that the complexes form ring-based and/or metal-based mixed-valence species, due to the remarkable intramolecular interactions between the two metal phthalocyanine units. The Vulcan XC-72 (VC)/Nafion(Nf)/Co2Pc2 modified glassy carbon electrode showed much higher catalytic performance towards oxygen reduction, compared to the VC/Nf/Zn2Pc2 modified one. It was found that the VC/Nf/Co2Pc2 catalyst is nearly insensitive to the presence of methanol. In the presence of 1 M methanol in the electrolyte, the catalytic performance of the Co2Pc2-based catalyst in oxygen reduction was much better than that of the Pt-based one. Thus, it was shown that the VC/Nf/Co2Pc2 catalyst can be a good alternative to VC/Nf/Pt as a cathode catalyst in direct methanol fuel cells.Publication Metadata only 7-Oxy-3,4-cyclohexenecoumarin Carrying Novel Zinc(II) and Indium(III) Acetate Phthalocyanines: Synthesis, Characterization, Photophysical and Photochemical Properties(WILEY-V C H VERLAG GMBH, 2019) YALÇIN, BAHATTİN; Karapinar, Beguemhan; Oezdemir, Muecahit; Salan, Uemit; Durmus, Mahmut; Yalcin, Bahattin; Bulut, MustafaIn this study, 7-hydroxy-3,4-cyclohexenecoumarin (1), two new phthalonitriles, 7-(2,3-dicyanophenoxy)-3,4-cyclohexene-coumarin (2), 7-(3,4-dicyanophenoxy)-3,4-cyclohexenecoumarin (3), were prepared. The phthalonitrile derivatives 2 and 3 were converted to the respective non-peripheral tetra, peripheral tetra 7-oxy-3,4-cyclohexenecoumarin substituted zinc(II) (4,6) and indium(III)acetate phthalocyanine (5,7) derivatives. All novel purified compounds (2-7) were characterized by elemental analysis, FT-IR, UV-vis, (HNMR)-H-1, 13CNMR, MALDI-TOF mass data. The spectral, photophysical (fluorescence quantum yields and lifetimes), and photochemical (singlet oxygen generation and photodegradation under light irradiation) properties of the synthesized Pcs (4-7) were studied in DMF, and the results were compared to determine the effects of the locations of substituents and the diversity of the central metal atom on these properties. The 7-oxy-3,4-cyclohexenecoumarin bearing phthalocyaninatozinc(II) and indium(III)acetate complexes showed good solubility in organic solvents such as chloroform, dichloromethane, tetrahydrofuran, acetone, DMF and DMSO. The fluorescence quenching behavior were investigated using 1,4-benzoquinone as a quencher. They have an acceptable level of singlet oxygen production, which determines the usability of phthalocyanines in photodynamic therapy applications and demonstrated appropriate photodegradation. The thermal properties of Pcs (4-7) were also investigated.