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61.
Elif Ece İlter Nuran Asmafiliz Zeynel Kılıç Leyla Açık Makbule Yavuz E. Burcu Bali Ali Osman Solak Fevziye Büyükkaya Hakan Dal Tuncer Hökelek 《Polyhedron》2010
The reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6, with N-alkyl-N-ferrocenylmethylethylene diamines, FcCH2NH(CH2)2NHR1 [R1 = Me (1) and Et (2)], and sodium [3-(N-ferrocenylmethylamino)-1-propanoxide] (3) produce spirocyclic monoferrocenyl tetrachlorophosphazenes (1a–3a). The tetrapyrrolidinophosphazenes (1b–3b) are prepared from the reactions of corresponding phosphazenes (1a–3a) with excess pyrrolidine. The reaction of 1a with excess morpholine affords geminal-morpholino phosphazene (1c), whilst the reactions of 2a and 3a give diethylaminotrimorpholino (2c) and fully substituted morpholino products (3c), respectively. The structural investigations of the compounds are examined by Fourier transform IR, MS, 1H, 13C, 31P NMR, DEPT, HETCOR, and HMBC techniques. The crystal structures of 3b and 3c are determined using X-ray crystallography. Cyclic voltammetric and chronoamperometric data show that compounds 1a–3a, 1b–3b, and 1c–3c exhibit electrochemically reversible one-electron oxidation of Fc redox centers which are hardly affected by the substituents on the phosphazene ring. The compounds 1b, 2b, 3b, and 3c are screened for antibacterial activities against Gram-positive and Gram-negative bacteria and for antifungal activities against yeast strains. In addition, the antituberculosis activities (in vitro) of these compounds are evaluated against INH-susceptible reference strain M. tuberculosis H37Rv, and six multi-drug resistant clinical M. tuberculosis isolates. Compound 2b is found to be the most active against the susceptible the reference strain. In addition, 1b, 2b, and 3c are active against all the multidrug-resistant clinical isolates at the highest concentrations. Gel electrophoresis data indicate that the compounds promote the formation of strand breaks in plasmid DNA. Almost all the concentrations lost of supercoiled DNA suggests that the compound 3b is very efficient plasmid-modifier. The compounds inhibit BamHI cleavage of pUC18 DNA while restricting HindIII. 相似文献
62.
Nadir Kiraz Ömer Kesmez Esin Burunkaya Leyla Budama Burçin Acar Meltem Asiltürk H. Erdem Çamurlu Ertuğrul Arpaç 《Journal of Sol-Gel Science and Technology》2010,56(3):227-235
This paper describes the preparation and characterization of glass films consisting of SiO2, Li2O, Na2O, K2O or MgO in varying compositions on stainless steel and aluminum substrates by sol–gel method. Silver phosphate or silver
incorporated zeolite was also introduced into the sols for obtaining antibacterial effect. The SiO2/Li2O/Na2O system having the composition of 85:5:10 wt% was found as the optimum for obtaining a stable sol and film formation. The
films were investigated by scanning electron microscopy (SEM) and electron dispersive analysis by X-ray (EDX), Fourier transformed
infrared (FTIR) spectroscopy, thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA). Homogenous films
having 300 ± 20 nm thicknesses were formed by spin coating and then by curing at 500 °C for 1 h. Obtained films had high adherence
to the metal substrates and they were also durable in acidic, basic or NaCl environments. They also presented a powerful antibacterial
effect against E. coli. 相似文献
63.
The title compound is crystallized in the monoclinic space group P21/c with cell parameters a = 7.499, b = 13.336, c = 19.390 Å, β = 99.716°, V = 1911.4 Å3, Z = 4, D cal = 1.273 Mg/m3 at T = 120 K. The structure is refined by full-matrix least-squares procedures to final R 1 = 0.0548 and wR 2 = 0.1089 for 3424 reflections. Two phenyl rings are noncoplanar with regard to each other and pyrrolidine core. The structure contains intramolecular hydrogen bond. 相似文献
64.
65.
Masoud Rahman Dr. Fariba Tajabadi Leyla Shooshtari Dr. Nima Taghavinia 《Chemphyschem》2011,12(5):966-973
Hollow structures show both light scattering and light trapping, which makes them promising for dye‐sensitized solar cell (DSSC) applications. In this work, nanoparticulate hollow TiO2 fibers are prepared by layer‐by‐layer (LbL) self‐assembly deposition of TiO2 nanoparticles on natural cellulose fibers as template, followed by thermal removal of the template. The effect of LbL parameters such as the type and molecular weight of polyelectrolyte, number of dip cycles, and the TiO2 dispersion (amorphous or crystalline sol) are investigated. LbL deposition with weak polyelectrolytes (polyethylenimine, PEI) gives greater nanoparticle deposition yield compared to strong polyelectrolytes (poly(diallyldimethylammonium chloride), PDDA). Decreasing the molecular weight of the polyelectrolyte results in more deposition of nanoparticles in each dip cycle with narrower pore size distribution. Fibers prepared by the deposition of crystalline TiO2 nanoparticles show higher surface area and higher pore volume than amorphous nanoparticles. Scattering coefficients and backscattering properties of fibers are investigated and compared with those of commercial P25 nanoparticles. Composite P25–fiber films are electrophoretically deposited and employed as the photoanode in DSSC. Photoelectrochemical measurements showed an increase of around 50 % in conversion efficiency. By employing the intensity‐modulated photovoltage and photocurrent spectroscopy methods, it is shown that the performance improvement due to addition of fibers is mostly due to the increase in light‐harvesting efficiency. The high surface area due to the nanoparticulate structure and strong light harvesting due to the hollow structure make these fibers promising scatterers in DSSCs. 相似文献
66.
Aytu? Okumu?Zeynel K?l?ç Tuncer HökelekHakan Dal Leyla Aç?kYa?mur Öner L. Yasemin Koç 《Polyhedron》2011,30(17):2896-2907
The reactions of hexachlorocyclotriphosphazene, N3P3Cl6, with mono (1 and 2) and bis(4-fluorobenzyl) diamines (3-5), FPhCH2NH(CH2)nNHR (RH or FPhCH2-), produce mono (1a and 2a) and bis(4-fluorobenzyl) monospirocyclophosphazenes (3a-5a). The tetraaminomonospirocyclophosphazenes (1b-2d) are obtained from the reactions of the partly substituted phosphazenes (1a and 2a) with excess pyrrolidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD), respectively. The tetrachlorobis(4-fluorobenzyl) monospirocyclophosphazenes (4a and 5a) with excess pyrrolidine, morpholine and DASD afford the fully substituted bis(4-fluorobenzyl) monospirocyclophosphazenes (4b, 4d-5d) in boiling THF. In addition, monochlorobis(4-fluorobenzyl) monospirocyclophosphazenes (4e and 4f) have also been isolated from the reactions with excess morpholine and DASD in boiling THF. The structural investigations of the compounds have been verified by elemental analyses, MS, FTIR, 1H, 13C, 19F (for 1d and 2d), 31P NMR, HSQC and HMBC techniques. The crystal structures of 3a, 4a, 5a and 2b have been determined by X-ray crystallography. The compounds 2a-5a, 1b-2d, 4b, 4d-5d, 4e and 4f have been screened for antibacterial effects on bacteria and for antifungal activity against yeast strains. The compounds 1b and 4b showed antimicrobial activity against three species of bacteria, Bacillus subtilis, Bacillus cereus and Staphylococcus aureus, and two fungi, Candida albicans and Candida tropicalis. Minimum inhibitory concentrations (MIC) were determined for 1b and 4b. The MIC values were found to be 5000 μM for each bacteria. The most effective compound, 4b has exhibited activity with a MIC of 312 μM for C. albicans and 625 μM for C. tropicalis. DNA-binding and the nature of the interaction with pBR322 plasmid DNA are studied. All of the compounds induce changes on the DNA mobility and intensity. Prevention of HindIII digestion with the compounds indicates that the compounds bind with AT nucleotides in DNA. 相似文献
67.
Erem Bilensoy Perran Moroy Yasemin ??rpanl? Tamer Bilensoy Sema ?al?? Leyla Mollamahmutoglu 《Journal of inclusion phenomena and macrocyclic chemistry》2011,69(3-4):309-313
Objective of this double-blind placebo-controlled study was to determine the efficacy of thermosensitive mucoadhesive gel loaded with 5-fluorouracil (5-FU):hydroxypropyl-ß-cyclodextrin (HP-ß-CD) complex via topical administration or intralesional injection for the treatment of human papilloma virus induced condyloma in 44 women. The diagnosis of human papilloma virus was established with clinical, histopathological and polymerase chain reaction techniques. Subjects were randomized into four parallel groups to evaluate topical or intralesional administration of drug-loaded or blank gel. The formulation used in the study consisted of 20% Pluronic PF 127 and 0.2% hydroxypropylmethylcellulose (HPMC) to render thermosensitive and mucoadhesive properties to the blank and drug-loaded gels. 5-FU was complexed to hydroxypropyl-ß-cyclodextrin to improve its solubility and this complex was loaded into thermosensitive gel to obtain controlled release of the cytotoxic drug in administration site over a two-week period cure regimen aiming therapeutic efficacy with lower 5-FU doses. Complete response was achieved in 61% of patients through intralesional administration while topical administration resulted in only 29% complete cure. Relapse rates of all therapy groups were significantly low in the 6-month follow-up time. 相似文献
68.
Akpan N. Ikot Elham Maghsoodi Saber Zarrinkamar Leyla Naderi Hassan Hassanabadi 《Few-Body Systems》2014,55(4):241-253
In this paper, we present the approximate bound state solutions of the Dirac equation within the framework of spin and pseudospin symmetries for Eckart potential for arbitrary κ—state using Nikiforov–Uvarov method. The tensor interactions of Coulomb-like and Yukawa-like form are considered and the effects of these tensors and the degeneracy removing role are discussed in detail. Numerical results and figures to show the effect of the tensor interactions are also reported. 相似文献
69.
Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation. 相似文献
70.
Azizollah Habibi Mohammad R. Yazdanbakhsh Leyla Mousavifar 《Journal of chemical crystallography》2008,38(9):701-704
Abstract The crystal structure of N-(tert-butyl)-1-(3,5-dioxo-2-phenyltetrahydro-4-isoxazolyl)-cyclohexane-carboxamide 1 has been determined. The title compound crystallized in the orthorhombic space group pbca with cell parameters, a = 10.6556(6) ?, b = 18.0132(11) ?, c = 19.5513(12) ?, v = 3752.7(4) ?3, Z = 8, D
cal = 1.269 Mg/m3 at T = 120 K. The structure refined by full-matrix least-squares procedures to find R
1 = 0.0463 and wR
2 = 0.0937 for 3059 reflections. The soxazole ring isn’t coplanar with the phenyl ring.
Index Abstract The crystal structure of N-(tert-butyl)-1-(3,5-dioxo-2-phenyltetrahydro-4-isoxazolyl)-cyclohexane-carboxamide 1 has been studied.
相似文献