Person: YALÇIN, BAHATTİN
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YALÇIN
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BAHATTİN
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Publication Metadata only 4-Fenil-2H-Kromen-2-On içeren periferal ve nonperiferal Cu ve Zn ftalosiyaninlerin sentezi ve fotostabilitelerinin incelenmesi(2021-12-20) GÖRGÜLÜ, AHMET ORHAN; YALÇIN, BAHATTİN; DİCLE C., ÖZDEMİR M., GÖRGÜLÜ A. O., YALÇIN B.Publication Metadata only Yeni metil (7-Hidroksi-8-Metil-2-Okso-2HBenzopiran-4-Yl) asetat kumarin içeren ftalosiyaninin kimyasal özelliklerinin incelenmesi(2022-09-28) DİCLE, CANSU; GÖRGÜLÜ, AHMET ORHAN; YALÇIN, BAHATTİN; ÖZDEMİR, MÜCAHİT; DOĞAN Y., DİCLE C., GÖRGÜLÜ A. O., YALÇIN B., BULUT M., ÖZDEMİR M.Halkasında karbon dışında atomlar olan ve oksijen bileşiklerinden meydana gelen büyük heterosiklik aromatik yapılar Kumarin (Coumarine) olarak tanımlar. Kumarin, adını 1820 yılında August Vogel tarafından izole edildiği tonka fasulyesinin (Dipteryx odorata Willd, Fabaceae) sınıf adı olan “coumarou” kelimesinden almıştır. IUPAC adı, 2H-kromen-2-on veya 2H-1-benzopiron-2-on’dur [1,2]. Kumarin ve türevleri doğada yaygın olarak; lavanta, tatlı yonca otu ve meyan kökü gibi bitkilerde; çilek, kiraz, kayısı ve tarçın gibi yiyeceklerde bulunmaktadır [3]. Kapalı formülü C9H6O2’dir. Mol kütlesi 146,14 g/mol, erime noktası 69- 71 °C ve kaynama noktası 301 °C’dir [4]. Kumarinler, absorbsiyon spektrumu ile iyi tanımlanırlar ve ultraviyole ışıkla uyarılınca karakteristik bir floresans gösterir. Ayrıca geniş bir fizyolojik aktiviteye sahiptirler [5]. Kumarin türevleri; yüksek floresans kuantum verimi, büyük kayma, mükemmel ışık stabilitesi ve düşük toksisite gibi birçok avantaja sahiptir [6]. Kumarin sentezlemede kullanılan metodlardan en yaygın olanları; Perkin, Pechmann, Knoevenagel, Reformatsky ve Witting Kondenzasyon reaksiyonlarıdır [7]. Yüksek simetriye sahip dört iminoizoindol ünitesi içeren 18 π elektronlu aromatik makrosiklik yapılar olan ftalosiyaninler, sahip oldukları bu π-elektron delokalizasyonu özelliği nedeni ile olağanüstü optik ve elektriksel davranışlar gösteren kimyasal ve termal olarak dayanıklı bileşiklerdir. İlk sentezlenen bakır ftalosiyanin molekülü merkez metale bağlı klor atomu sayısının arttırılması ile maviden yeşile doğru giden bir renk değişimi göstermiştir. Çoğu ftalosiyanin bileşiği yüksek vakumda buharlaştırılabilip, süblimleştirilebilen bileşiklerdir. Öte yandan termal kararlılıkları sebebiyle çoğunun erime noktası yoktur [8]. Bugüne kadar ftalosiyaninlerde merkez atom olarak 70‘den fazla farklı element kullanılmıştır. Ftalosiyanin ligandı metallerin hemen hepsiyle koordine edilebilir.Publication Metadata only Novel lutetium(III) phthalocyanine-coumarin dyads; synthesis, characterization, photochemical, theoretical and antioxidant properties(ELSEVIER SCIENCE SA, 2021) YALÇIN, BAHATTİN; Ozdemir, Mucahit; Koksoy, Baybars; Yalcin, Bahattin; Taskin, Turgut; Selcuki, Nursel Acar; Salan, Umit; Durmus, Mahmut; Bulut, MustafaIn 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).Publication Metadata only Sars-cov-2 omicron varyantinin spi̇ke protei̇ni̇ne karşı doğal kumari̇nleri̇n taranması: in silico bi̇r hesaplama yaklaşımı(2022-02-27) ÖZDEMİR, MÜCAHİT; YALÇIN, BAHATTİN; Özdemir M., Yalçın B., Öztürkkan F. E., Akbaba G. B., Sertçelik M., Necefoğlu H.In this study, the interactions of coumarin derivatives with the spike protein of the coronavirus Omicron variant were investigated with the help of Molecular Docking studies. When the substrate effects of the compounds against the SARS-CoV-2 Omicron variant Spike protein are examined in silico, it has been determined that the compounds exhibit moderate antagonistic effect. There are some interactions such as hydrogen bonding, carbon-hydrogen bonding, π-π stacking, π-anion, π cation, π-alkyl and alkyl interactions between coumarin derivatives and against Omicron variant’s spike protein of Sars-CoV-2.Publication Metadata only Nutrient dynamics and eutrophication in the Sea of Marmara: Data from recent oceanographic research(ELSEVIER SCIENCE BV, 2017) YALÇIN, BAHATTİN; Yalcin, Bahattin; Artuz, M. Levent; Pavlidou, Alexandra; Cubuk, Soner; Dassenakis, ManosThis work was implemented to study the physicochemical and biological characteristics of the Sea of Marmara and the Turkish straits (TSS: Bosporus and Dardanelles straits) for the period 2010-2013 and to calculate winter and summer fluxes of nutrients (nitrates, phosphates) between the Aegean and Black Seas through the TSS. The brackish Black Sea waters reach the Dardanelles Strait with modified biochemical properties. The salinity and phosphates of the surface waters increased westwards. Biologically labile nutrients of Black Sea origin are utilized through biological processes in the Marmara Sea. On the other hand, increase of nutrients due to land based sources has led to eutrophication problems in the area. The sub surface water layer of Mediterranean origin is oxygen depleted (saturation < 30%) and rich in nutrients. Higher oxygen values indicated water mixing of the Sea of Marmara during winter 2012. Ammonium was the predominant form of inorganic nitrogen. The study area has been classified from Moderate to Bad trophic status. Izmit Bay also faced serious eutrophication problems together with hypoxic conditions below the halocline. Nutrient fluxes through the TSS showed temporal variation in the upper and lower layers related to changes in both nutrient concentrations and the water mass volume fluxes. Surface nitrates and phosphates outflux from the Sea of Marmara to the Aegean Sea was higher than the influx from the Black Sea through Bosporus strait, indicating high enrichment of nutrients in the Sea of Marmara from anthropogenic sources. (C) 2017 Elsevier B.V. All rights reserved.Publication Metadata only Keto-Kumarin grubu içeren ftalosiyaninlerin sentezi ve elektrokimyasal özelliklerinin incelenmesi(2021-10-08) YALÇIN, BAHATTİN; ABLİATİPOVA A., ÖZDEMİR M., YALÇIN B., BULUT M.Publication Metadata only Synthesis and characterization of Cu(II) complexes of pyrazine-2,3-dicarboxylicacid(PERGAMON-ELSEVIER SCIENCE LTD, 2011) YALÇIN, BAHATTİN; Tascioglu, Sulin; Aydin, Adnan; Yalcin, Bahattin; Kaki, Esra; Andac, Omer; Buyukgungor, Orhan; Kosar, BasakFour copper(II) coordination polymers, {[Cu(pz(COO)(2))(H2O)](4)center dot HBr}(n) (1). {[Cu(pz(COO)(2))(NH3)(2)]center dot H2O}(n) (2), {[Cu3H2(pz(COO)(2))(4)(H2O)(3)]center dot 2H(2)O}(n) (3) and {[Cu-2(pz(COO)(2))(2)(NH3)(2)(H2O)(3)][Cu(pz(COO)(2))(NH3) (H2O)(2)][Cu(pz(COO)(2))(NH3)(H2O)]center dot 2H(2)O}(n) (4) were synthesized using pyrazine-2,3-dicarboxylic acid, CuBr2, 2-(2-aminoethylamino)ethanol/triethanol amine/ammonia in a methanol:water (1:1) solution, and the mixed ligand complexes were characterized by spectroscopic methods, thermal and elemental analysis, and magnetic susceptibility. Complexes 2 and 4 were also characterized by means of single crystal X-ray crystallography. The characterizations show that the complexes have polynuclear molecular structures, except for complex 2, and all of the complex structures form polymeric chains. Complex 4 has a pseudo-merohedral twin structure. (C) 2011 Elsevier Ltd. All rights reserved.Publication Metadata only 1,2,3-Triazole incorporated coumarin carrying metal-free, Zn(II), Mg(II) phthalocyanines: Synthesis, characterization, theoretical studies, photophysical and photochemical properties(ELSEVIER SCIENCE SA, 2020) YALÇIN, BAHATTİN; Ozdemir, Mucahit; Abliatipova, Aziza; Benian, Sueda; Yalcin, Bahattin; Salan, Umit; Durmus, Mahmut; Bulut, MustafaIn this study, the preparation of two novel phthalonitrile compounds, 7-(propargyloxy)-3-(3,4-dicyanophenoxyphenyl)coumarin (1), and 7-(propargyloxy)-3-(2,3-dicyanophenoxy-phenyl)coumarin (2) were performed. Two new coumarinyl-1,2,3-triazole hybrids, (1-phenethy1-1H41,2,A-triazole 4 yl) 7 methyleneoxy 3 [F. (3,4 dicya nophenoxy)phenyl]-coumarin (3), and (1-phenethy1-1H-[1,2,3]-triazole 4 yl) 7 methyleneoxy 3 [F. (2,3 dicya nophenoxy)phenyl]-coumarin (4), were synthesized by the copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reaction of 2-(azidoethyl)benzene with terminal ethynyl bearing coumarin derivatives (1 or 2). These novel phthalonitrile derivatives (3 and 4) were converted into their peripheral (5-7) and non-peripheral (8-10) metal-free, zinc(II) and magnesium(II) phthalocyanine counterparts. The synthesized phthalocyanine derivatives are first examples on the phthalocyanine-coumarin derivatives bearing triazole ring. The structures of all these novel compounds were characterized by variety of spectroscopic techniques including FT-IR, UV-vis, H-1 NMR, MALDI-TOF MS and elemental analysis. The photophysicochemical properties of all studied Pcs (5-10) were determined in dimethyl sulfoxide. The zinc(II) and magnesium(II) phthalocyanines bearing triazole containing coumarin substituents appear to be useful as Type II photosensitizers because the singlet oxygen quantum yields ranged in acceptable values from 0.17 to 0.49 confirmed that these phthalocyanines can be suggested as photosensitizers in Photodynamic Therapy applications. Geometry optimization, frequency analysis and molecular orbital energy values of coumarin/triazole substituted phthalocyanine were performed in Density Functional Theory method using the B3LYP/LANL2DZ level of theory.Publication Metadata only Synthesis in water-free DMF, characterization, electrical, and gas sensing properties of bis[2-(2-aminoethylamino)ethanol]copper(II) dibromide(SPRINGER INTERNATIONAL PUBLISHING AG, 2013) YALÇIN, BAHATTİN; Tascioglu, Sulin; Yalcin, Bahattin; Dumludag, Fatih; Kaki, Esra2-(2-Aminoethylamino)ethanol (L) reacts with cupric bromide in dimethylformamide to give a mononuclear complex of Cu(II) [L2Cu]Br-2, with six-coordinate distorted octahedral geometry, in which two molecules of tridentate (N,N,O) ligand are involved. The structure was confirmed by spectroscopic methods, elemental and thermogravimetric analyses, and magnetic measurements. Optimization of possible configurations indicated the formation of the trans structure of the complex. Experimental results indicate that the investigated complex, bis[2-(2-aminoethylamino)ethanol] copper(II) bromide, behaves as a semiconductor in the studied temperature range of 298-388 K. Gas sensing properties of the film for the volatile organic compounds (VOCs): acetone, tetra-chloromethane, chloroform, ethanol, and methanol, were also investigated as a function of vapor concentration and temperature in dark. The film showed maximum sensitivity to tetrachloromethane and ethanol vapors at room temperature. Responses of the film to the tested gases are reversible.Publication Metadata only Synthesis, characterization, crystal structure, electrochemical studies and biological evaluation of metal complexes with thiosemicarbazone of glyoxylic acid(PERGAMON-ELSEVIER SCIENCE LTD, 2018) ÖZKAYA, ALİ RIZA; Huseynova, Mansura; Taslimi, Parham; Medjidov, Ajdar; Farzaliyev, Vagif; Aliyeva, Mahizar; Gondolova, Gulnar; Sahin, Onur; Yalcin, Bahattin; Sujayev, Afsun; Orman, Efe Baturhan; Ozkaya, Ali Riza; Gulcin, IlhamiCobalt and nickel nitrates form with thiosemicarbazone of glyoxylic acid (H(2)GAT) complexes of empirical composition Co(C3H4N3O2S)(2)center dot 2H(2)O, Ni(C3H4N3O2S)(2)center dot 2H(2)O and Ni(C3H6N3O2S)(2). X-ray diffraction studies have shown that the Co(HGAT)(2)center dot 2H(2)O, Ni(HGAT)(2)center dot 2H(2)O complexes are mononuclear, in which the coordination around the metal is octahedral, made up of two sulfur atoms, two nitrogen atoms and two oxygen atoms from two ligands. By the interaction of NiCl2 center dot H2O with 2-[2-(aminothioxomethyl)hydrazinyl] acetic acid (H(2)TAA) instead of the expected the metal thiosemicarbazonate complex with the hydrogenated on the azomethine group ligand was obtained. The redox properties of these compounds were also investigated by voltammetry on Pt in dimethylsulfoxide/tetrabutylammonium perchlorate. These thiosemicarbazone of glyoxylic acid derivatives had effective inhibition against alpha-glycosidase, cytosolic carbonic anhydrase I and II isoenzymes, butyrylcholinesterase and acetylcholinesterase. K-i values were found as 26.12-36.58 nM for hCA I, 20.73-40.78 nM for hCA II, 184.30-642.18 nM for AChE, 123.67-342.37 nM for BChE, and 14.66-45.62 nM for alpha-glycosidase. (C) 2018 Elsevier Ltd. All rights reserved.