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91.
Duygu nci Rahmiye Aydn
zgür Vatan Huzeyfe Huriyet Yunus Zorlu Bünyemin out Nilüfer inkl 《应用有机金属化学》2019,33(1)
In this paper, three new copper (II) complexes, [Cu(4‐mphen)(tyr)(H2O)]ClO4 (1) , [Cu(5‐mphen)(tyr)(H2O)]ClO4·1.5H2O (2) and [Cu (tmphen)(tyr)(NO3)]0.5H2O (3) (4‐mphen: 4‐methyl‐1,10‐phenanthroline, 5‐mphen: 5‐methyl‐1,10‐phenanthroline, tmphen: 3,4,7,8‐tetramethyl‐1,10‐phenanthroline and tyr: L‐tyrosine), were synthesized and characterized using elemental analyses, FT‐IR, ESI‐MS, cyclic voltammetry and single‐crystal X‐ray diffraction. It was found that the complexes adopt a distorted five‐coordinate square pyramidal geometry. The interaction of the three complexes with calf thymus DNA was also investigated using UV–visible absorption spectra, ethidium bromide and Hoechst 33258 displacement assay and thermal denaturation. The DNA cleavage activity of the complexes, monitored using gel electrophoresis, showed significant damage of the pUC19 plasmid DNA. Binding activity of bovine serum albumin (BSA) reveals that these complexes can strongly quench the fluorescence of BSA through a static quenching mechanism. The results suggested that interaction of the complexes with DNA occurred through a partial intercalation into the minor grooves of DNA. In addition, interaction of the complexes with bovine serum albumin quenched the fluorescence emission of the tryptophan residues of the protein binding constants and thermodynamic parameters were obtained from the fluorescence quenching experiments at different temperatures. Free radical scavenging activities of the complexes were determined by various in vitro assays such as 1,1‐diphenyl‐2‐picryl‐hydrazyl free radicals (DPPH˙) and H2O2 scavenging methods. In addition, the cytotoxicity of these complexes in vitro on tumor cell lines (Caco‐2 and MCF‐7) was examined by XTT and showed better antitumor effect on the tested cells. ROS (reactive oxygen species) and comet experiments are consistent with each other and these complexes lead to DNA damage via the production of ROS. The effect of the hydrophobic properties of the synthesized complexes on DNA and BSA binding activities were discussed. 相似文献
92.
Three novel water‐soluble copper(II) complexes – {[Cu(phen)(trp)]ClO4·3H2O}n ( 1 ), {[Cu(4‐mphen)(trp)]ClO4·3H2O}n ( 2 ) and [[Cu(dmphen)(trp)(MeOH)][Cu(dmphen)(trp)(NO3)]]NO3 ( 3 ) (phen: 1,10‐phenanthroline; 4‐mphen: 4‐methyl‐1,10‐phenanthroline; dmphen: 4,7‐dimethyl‐1,10‐phenanthroline; trp: l ‐tryptophan) – have been synthesized and characterized using various techniques. Complexes 1 and 2 are isostructural, and exist as one‐dimensional coordination polymers. Complex 3 consists of two discrete copper(II) complexes containing [Cu(trp)(dmphen)(MeOH)]+, [Cu(trp)(dmphen)(NO3)] and one nitrate anion. The binding interaction of the complexes with calf thymus DNA (CT‐DNA) was investigated using thermal denaturation, electronic absorption and emission spectroscopic methods, revealing that the complexes could interact with CT‐DNA via a moderate intercalation mode. The binding activity of the complexes to CT‐DNA follows the order: 3 > 2 > 1 . The pUC19 DNA cleavage activity of the complexes was investigated in the absence and presence of external agents using the agarose gel electrophoresis method. Especially, in the presence of H2O2 as an activator, the pUC19 DNA cleavage abilities of the complexes are clearly enhanced at low concentration. Addition of hydroxyl radical scavenger dimethylsulfoxide shows a marked inhibition of the pUC19 DNA cleavage activity of the complexes. In vitro cytotoxic effect of the complexes was examined on human tumor cell lines (Caco‐2, A549 and MCF‐7) and healthy cells (BEAS‐2B). The potent cytotoxic effect of complex 3 , with IC50 values of 1.04, 1.16 and 1.72 μM, respectively, is greater relative to clinically used cisplatin (IC50 = 22.70, 31.1 and 22.2 μM) against the Caco‐2, A549 and MCF‐7 cell lines. 相似文献
93.
Dursun Ali Köse Birgül Zümreoglu‐Karan Prof. Dr. Tuncer Hökelek Ertan Sahin 《无机化学与普通化学杂志》2009,635(3):563-566
The structure of [B6H9NaO14, H3BO3, 6H2O] was determined by single‐crystal X‐ray diffraction and further analyzed by FTIR spectroscopy and differential thermal/thermogravimetric analysis. The asymmetric unit contains Na–O polyhedra (distorted octahedron), [B6O8(OH)3]– fundamental building blocks, one free water molecule and one free H3BO3 molecule. In the hexaborate anion, three B3O3 rings are linked by a common oxygen atom with five trigonal and one tetrahedral boron atoms. The hexaborate group is also linked to the oxygenated environment of the sodium atom by three other six‐membered rings, each of which involve two boron atoms, three oxygen atoms, and sodium as the joint atom. 相似文献
94.
In this study, the electrical, optical and mechanical properties of polystyrene (PS) thin films added graphene nanoplatelet (GNP) have been investigated. Surface conductivity (σ), absorbance intensity (A) and tensile modulus of these composite films have increased with increasing the content of GNP in the composite. The increase in the electrical and optical properties of the PS/GNP composite films has been interpreted by site and classical percolation theory, respectively. The electrical and the optical percolation thresholds of PS/GNP composite films were determined as Rσ?=?23.0?wt.% and Rop?=?13.0?wt.%, respectively. While the conductivity results have been attributed to the classical percolation theory, the optical results have attributed to the site percolation theory. The electrical (βσ) and the optical (βop) critical exponents were calculated as 2.54 and 0.40, respectively. The tensile modulus and the tensile strength of the PS/GNP composites increased with the increasing of GNP content in the PS. But, the toughness of the composites fluctuated with GNP addition. 相似文献
95.
Benzonorbornadiene and heterobenzonorbornadiene were reacted with dimedone/acetylacetone and Mn(OAc)3 in the presence and absence of Cu(OAc)2. The reaction of benzonorbornadiene with dimedone gave mainly the dihydrofuran addition product, whereas the reaction with acetylacetone produced a rearranged product in addition to the dihydrofuran derivative. On the other hand, oxanorbornadiene gave unusual products such as the cycloproponated compound and a product arising from the incorporation of 2 mol of dimedone. The reaction of azanorbornadiene with 1,3-dicarbonyl compounds and Mn(OAc)3 always produced rearranged products. The mechanism of formation of the products is discussed. We generally observe that the cyclization reaction takes place after the oxidation of the initially formed radical. 相似文献
96.
Ilter EE Asmafiliz N Kiliç Z Isiklan M Hökelek T Caylak N Sahin E 《Inorganic chemistry》2007,46(23):9931-9944
The reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6, with N/O donor-type N-alkyl-o-hydroxybenzyl- and o-hydroxynaphthylamines result in novel mono- (3a, 4a and 4b), di- (5a and 5b), and tri- (3b, 6a, and 6b) spirocyclic phosphazene derivatives. The tetrakis-pyrrolidinophosphazene, 3b, has been obtained from the reaction of partly substituted compound 3a with the excess pyrrolidine in tetrahydrofuran. The relationship between the endocyclic NPN (alpha) and exocyclic NPO (alpha') bond angles of the analogous spirocyclic phosphazenes with the deltaP shifts of NPO phosphorus atoms have been presented. It was observed that there is a linearity between alpha angles and deltaP shifts, while no linear relationship has been observed for alpha' angles. In addition, we have found the correlation between Delta(P-N) and deltaNPO shifts, which implies a linear relationship. Delta(P-N)=(a-b), where a and b are the average lengths of two adjacent P-N bonds. The structural investigations of all of the compounds have been made by elemental analyses; mass spectrometry; Fourier transform infrared spectroscopy; one-dimensional 1H, 13C, and 31P NMR; distortionless enhancement by polarization transfer; and two-dimensional correlation spectroscopy, heteronuclear shift correlation, and heteronuclear multiple-bond correlation homo- and heteronuclear correlation techniques. The solid-state structures of 3a, 4a, 4b, and 5a have been determined by X-ray crystallographic techniques. The asymmetric units of compounds 3a and 4a contain two independent molecules, and 3a has strong intermolecular N-H...N hydrogen bonds linking three phosphazene rings. The molecular structure of 6a looks like a propeller where the chemical environment of P1 is different from that of P2 and P3. On the other hand, compounds 5a and 5b are expected to exist as cis- or trans-geometric isomers and to be in cis (meso) or trans (racemic) configurations. The crystallographic and preliminary chiral solvating agents results show that both of them are trans (racemic). In addition, 6a and 6b are also expected to exist as cis-trans-trans- and cis-cis-cis-geometric isomers; both of them are found to be in cis-trans-trans geometries. According to the two-dimensional spectroscopic data, the possible conformations of 3a and 4a in CDCl3 are the same with the solid-state structures. 相似文献
97.
Caliskan Suleyman Yildirim Ertan Anakok Deniz Akin Cete Servet 《Journal of Solid State Electrochemistry》2022,26(2):549-557
Journal of Solid State Electrochemistry - In this study, a new amperometric biosensor for creatinine determination was developed. For this purpose, a polypyrrole-polyvinylsulfonate film was... 相似文献
98.
Filiz Maden Yücel Ertan Yildirim Tuncer Caykara 《Journal of polymer science. Part A, Polymer chemistry》2019,57(10):1140-1146
2‐Hydroxyethyl acrylamide was successfully polymerized via single‐electron transfer initiation on the silicon surface and propagation through the reversible addition–fragmentation chain transfer (SET‐RAFT) polymerization at ambient temperature for different polymerization times. This work is the first time application of the surface‐initiated SET‐RAFT mechanism to afford the preparation of well‐defined poly(2‐hydroxyethyl acrylamide) [poly(HEAAm)] brushes at ambient temperature. The polymerization was well controlled and produced poly(HEAAm) brushes on the silicon surface with a well‐defined target molecular weight. The controlled nature of the polymerization was further demonstrated in the presence of sulfur atoms at the chain ends in X‐ray photoelectron spectroscopy experiments. The grafting density (σ, chains nm?2) and the average distance between grafting points (D, nm) were found to be 0.42 chains nm?2 and 1.74 nm, respectively, indicating moderate grafting density. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1140–1146 相似文献
99.
Synthesis,Characterization and Unusual Reactivity of Vinylbenziodoxolones—Novel Hypervalent Iodine Reagents 下载免费PDF全文
Elin Stridfeldt Alexandra Seemann Dr. Marinus J. Bouma Dr. Chandan Dey Dr. Anne Ertan Prof. Berit Olofsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(45):16066-16070
A novel type of hypervalent iodine(III) reagents, vinylbenziodoxolones (VBX), has been synthesized in a one-pot reaction from 2-iodobenzoic acid. VBX is bench stable, has been thoroughly characterized and the cyclic structure is supported by X-ray analysis. The reactivity of VBX was investigated in vinylation of nitrocyclohexane, and delivered vinylated products with opposite regioselectivity compared to acyclic vinyl(aryl)iodonium salts. The reagents could become a powerful tool in vinylation reactions under both metal-free and metal-catalyzed conditions. 相似文献
100.
Effects of multiwall carbon nanotube (MWCNT) addition on the electrical conductivities, optical transparencies and fluorescence emissions of poly(vinyl acetate-co-butyl acrylate) (P(VAc-co-BuA))/MWCNT composite films were studied. Optical transmission, fluorescence emission and two point probe resistivity techniques were used to determine the variations of the optical, fluorescence and electrical properties of the composites, respectively. Transmitted photon intensity (I tr), fluorescence emission intensity (I fl) and surface resistivity (ρ s) of the composite films were monitored as a function of MWCNT mass fraction (M) at room temperature. All these measured quantities of the composites were decreased by increasing the content of MWCNT in the composite. The conductivity and the optical results were attributed to the classical and site percolation theories, respectively. The fluorescence results, however, possessed both the site and classical percolation theories at low and high MWCNT content regions, respectively. 相似文献