Kenan Koran

Coumarin Based Highly Selective “off-on-off” Type Novel Fluorescent Sensor for Cu 2+ and S 2− in Aqueous Solution

AbstractSolvent free synthesis of 6,7-dihydroxy-3-(3-chlorophenyl) coumarin (CFHC) was designed and obtained by the interaction of 2-(2,4,5-trimethoxyphenyl)-1-(3-chlorophenyl)acrylonitrile with pyridinium hydrochloride in the presence of silica gel by using microwave irradiation. The characterization of CFHC was confirmed by FT-IR, 1H, 13C, 13C–APT and 2D HETCOR spectroscopy methods. The optical behavior of CFHC towards metal ions was investigated by UV-visible and fluorescence spectroscopy. CFHC showed “on–off” type fluorescence response towards Cu2+ with high selectivity in aqueous solution (CH3CN/H2O, 9/1, v/v). Once binding with Cu2+, CFHC-Cu2+ complex also displayed high selectivity for sulfide, resulting in “off–on” type sensing of sulfide anion. Graphical abstractVisual fluorescence changes upon addition of various metal ions (5.0 eq.) to CFHC in CH3CN/H2O (90:10, v/v) under UV excitation (365 nm)

Structural, electrical and photoresponse properties of si-based diode with organic interfacial layer containing novel cyclotriphosphazene compound

The electrical and photoresponse properties of Al/p-Si/organic layer/Al diode were investigated. Organic layer containing novel 2,2-bis[spiro(7,8-dioxy- 4-methylcoumarin)]-4,4,6,6-bis[spiro(2’,2”-dioxy-1’,1”- biphenylyl)]cyclotriphosphazene compound was coated by drop casting method on p-Si having ohmic contact. The structural characterization of novel cyclotriphosphazene compound was confirmed by using 1H, 13C and 31P-NMR, elemental analysis and FT-IR spectroscopic techniques. The diode exhibits a photoconducting and photodiode behavior under solar light illumination. The electrical parameters such as ideality factor, barrier height and series resistance of the diode were determined from I-V characteristics. It is seen that the photocurrent of the diode under illumination is higher than dark current. Also, the frequency dependence of capacitance (C) and conductance (G) was explained on the basis of interface states. It is evaluated that the hybrid photodiode can be used as a photosensor in organic photodetector applications.

Synthesis, structural and thermal characterizations and in vitro cytotoxic activities of new cyclotriphosphazene derivatives

GRAPHICAL ABSTRACT ABSTRACT We investigated the cytotoxic effects of the newly synthesized cyclotriphosphazene derivatives on A2780 (ovarian), PC-3 and LNCaP (prostate) cancer cell lines. 4′-hydroxy-substituted-chalcone compounds (2–8) were reacted with diphenyl-cyclotriphosphazene (DPP) in the presence of acetone/K2CO3 in order to obtain novel cyclotriphosphazene compounds (DPP 2–8). The structures of DPP 2–8 were characterized by MALDI-TOF mass spectrometry, FT-IR, elemental analysis, 1H, 13C-APT, and 31P NMR measurements. The thermal properties of all phosphazene compounds have been studied after synthesis and characterization procedure. The cytotoxic effects of DPP 2–8 were examined primarily by applying the MTT method based on the measurement of mitochondrial activity. In this regard, several phosphazene compounds have shown high chemotherapeutic effect at low dose (p < 0.05). When the cytotoxic effects of DPP 2–8 at doses of 1, 5, 25, 50 and 100 µM on A2780 cells were examined, it was observed that DPP-3, DPP-4, DPP-5 and DPP-7 were more effective than other derivatives suggested by their high Log IC50 values (p < 0.05). The compounds DPP 2–8 possess cytotoxic activity against PC-3 and LNCaP cells (especially compounds DPP-4 and DPP-5, p < 0.05).

Synthesis, structural and thermal characterizations, dielectric properties and in vitro cytotoxic activities of new 2,2,4,4-tetra(4′- oxy-substituted-chalcone)-6,6-diphenylcyclotriphosphazene derivatives

In this study, we aimed to investigate the relationship between the cytotoxic and dielectric properties of newly synthesized 2,2,4,4-tetra(4′-oxy-substituted-chalcone)-6,6-diphenylcyclotriphosphazene derivatives (3–10). Firstly, 2,2,4,4-tetrachloro-6,6-diphenyl cyclotriphosphazene (2) was obtained through Friedel Crafts alkylation in the presence of hexachlorocyclotriphosphazene, benzene and triethylamine and anhydrous AlCl3. The compounds 3–10 were synthesized from the reaction of the hydroxychalcone compounds (1a–h) with 2 in the presence of K2CO3 and within the acetone solvent for the first time and their dielectric constant, dielectric loss factor and ac conductivity of compounds 3–10 were examined through the impedance analyzer as a function of frequency. The in vitro cytotoxic activities of compounds 3–10 in five different concentrations (1, 5, 25, 50, and 100 µM) were analyzed by colorimetric MTT assay which is based on reduction of MTT salt by mitochondria of alive cells over the human ovarian cancer (A2780) and human prostate cancer (PC-3 and LNCaP) cell lines. The LogIC50 values of 3–10 were calculated by using a Graphpad prism 6 programs on a computer. The obtained results suggests that the compounds have a powerful cytotoxic activity (especially A2780, p < 0.05).

Selective and sensitive fluorescent and colorimetric chemosensor for detection of CO 3 2- anions in aqueous solution and living cells

A new colorimetric and fluorescent chemosensor for visual determination of carbonate ions was developed by the microwave assisted solvent free synthesis of 7,8-dihydroxy-3-(4-methylphenyl) coumarin (DHMC). The structural characterization of DHMC was confirmed by microanalysis and spectroscopy methods (MALDI-TOF, FT-IR, 1H NMR, 13C NMR, and 2D HETCOR). The binding behaviors of DHMC were investigated towards various anions by UV-vis and fluorescence spectroscopy. DHMC showed a selective and sensitive fluorometric and colorimetric responses towards carbonate ion over other anions. The detection limit of CO32- was found to be 1.03 µM. Moreover, the fluorescence imaging in living cells suggests that DHMC has a great potential in the biological imaging application. It has been demonstrated that DHMC can be used as a rapid and reliable sensor for the determination of carbonate anion in a variety of practical applications.

Metallo-Phthalocyanines Based Photocapacitors

The novel metallo-phthalocyanines (4–6) were obtained from the reactions of gereniol substituted phthalonitrile compound (3) with corresponding metal salts (Co (II), Cu (II) and Zn (II) acetates). The electrical and photoconductive properties of Al/p-Si/organic complex/Al devices with cobalt (4), copper (5) and zinc (6) phthalocyanines complexes containing geraniol as side groups were studied by using optoelectrical measurements at various sunlight intensites. The transient photocurrent and photocapacitance were measured as a function of time. Experimental results indicate that the prepared diodes exhibit both photodiode and photocapacitive behavior. Consequently, it is evaluated that the studied devices can be used as a photocapacitor in optical applications.

Erratum to: Synthesis, characterization, and biological evaluation of new oxime-phosphazenes

Erratum to: Res Chem Intermed (2013) 39:1109–1124DOI 10.1007/s11164-012-0670-2We have discerned that, in our work, one of the authors made mistakes in thebiological result tables (Tables 1, 2). Because discussions and conclusions weremade by evaluation of data that was presented in these tables, the discussions andconclusions, abstract, and sections of the article also contain mistakes. We apologiseto the Publisher, scientific world, Editorial Board of Research on ChemicalI˙ntermediates, and all readers for these great mistakes. The tables, and the relatedparts of abstract, discussions and conclusions sections of the article are corrected inthis erratum.Tables 1 and 2 are corrected as below: