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11.
Murat Acemoglu Roland Prewo Jost Hans Bieri Conrad Hans Eugster 《Helvetica chimica acta》1984,67(1):175-183
Synthesis and X-Ray Structure of (6′RS,8′RS,2E)- and (6′RS,8′SR,2E)-3-Methyl-3-(2′,2′,6′-trimethyl-7′-oxabicyclo[4.3.0]non-9′-en-8′-yl)-2-propenal ([(5RS,8RS)- and (5RS,8SR)-5,8-Epoxy-5,8-dihydro-ionylidene]acetaldehyde) To check our previous spectroscopic assignments of the structures of trans- and cis-substituted furanoid end groups of carotenoid-5,8-epoxides, we now have synthesized the title compounds. An X-ray structure determination of a single crystal of the trans-isomer (±)- -10A is in agreement with the 1 H-NMR spectroscopic arguments: isomers with Δδ (H? C(7), H? C(8)) = 0.15–0.22 ppm and J > 1.4 for H? C(7) belong to the cis-series; Δδ in trans-compounds is < 0.07 ppm, and H? C(7) appears as a broad singulett. 相似文献
12.
Arzu Gumus Murat Bozdag Atilla Akdemir Andrea Angeli Silvia Selleri Fabrizio Carta Claudiu T. Supuran 《Molecules (Basel, Switzerland)》2022,27(14)
A novel series of thiosemicarbazide-substituted coumarins was synthesized and the inhibitory effects against four physiologically relevant carbonic anhydrase isoforms I, II, IX and XII showed selective activities on the tumor-associated IX and XII isozymes. Molecular modeling studies on selected compounds 14a and 22a were performed. The binding modes of such compounds were determined assuming their enzymatically active structures (i.e., cinnamic acid) in the thermodynamically favored, and not previously explored, E geometry. Molecular modelling suggests multiple interactions within the enzymatic cavity and may explain the high potency and selectivity reported for the hCAs IX and XII. 相似文献
13.
Cemil İbiş Murat Onul 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1881-1889
2-Nitrodiene compound 1 was stirred with p-fluorothiophenol for a long time and compound 3 was obtained. Compound 1 gave bis(thio)substituted 2-nitrodiene compound 4 and tris(thio)substituted compound 5 with 2 moles of p-fluorothiophenol in the presence of NaOH in ethanol. The compounds 9a–g have been prepared from 8a–g and 3. Compound 7 was obtained from the reaction of mono(thio)substituted 2-nitrodiene with morpholine. Compound 3 gives 11a–d in the reaction with piperidines in CH2Cl2 (or ether). Compound 13a–b have been obtained from the reaction of compound 3 with primary amines 12a–b. Compound 3 gives 15 and 16 in the reaction with 2,5-dimethylpiperazine in CH2Cl2. 相似文献
14.
M. Murat Ozmen 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):1215-1225
A series of strong polyelectrolyte gels were prepared in aqueous solution, using the sodium salt of 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) as the monomer and N,N'‐methylene(bis)acrylamide (BAAm) as a crosslinker. The gels were both prepared below (?22°C) and above (25°C) the bulk freezing temperature of the water, producing cryogels and hydrogels, respectively. The crosslinker (BAAm) content was set at 17 mol%, while the initial monomer concentration Co was varied over a wide range. It was found that, at ?22°C, a macroscopic network starts to form at an initial monomer concentration of as low as 0.1 w/v%. In contrast to the conventional hydrogels formed at 25°C, the cryogels have a discontinuous morphology consisting of polyhedral pores of sizes 100–102 μm. The cryogels exhibit superfast swelling properties, as well as reversible swelling–deswelling cycles in water and acetone. An increase in the initial monomer concentration from 2.5 to 10% further increases the response rate of the cryogels due to the simultaneous increase of the porosity of the networks. 相似文献
15.
2-Arylazo-5,5,10,10,15,15,20,20-octamethylcalix[4]pyrroles (azo-OMCPs) have been synthesised by the reaction of calix[4]pyrrole with aryldiazonium chloride in 15–45% yields. The solution-state binding studies of the synthesised hosts were investigated by absorption spectroscopy and 1H NMR in DMSO and CDCl3, respectively. These receptors, appended with electron-donating and electron-withdrawing groups, displayed enhanced affinity and selectivity for fluoride anion. Well-defined colour change in the visible region of the spectrum was observed upon addition of fluoride ion in DMSO solution of azo-OMCPs. Detailed NMR studies in CDCl3 revealed that azo-OMCPs with nitro and chloro groups have higher binding affinity for fluoride ion. 相似文献
16.
Murat Ates Nesimi Uludag Tolga Karazehir Fatih Arican 《Journal of Solid State Electrochemistry》2013,17(9):2417-2427
In this work, (3,6-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(4-vinylbenzyl)-9H-carbazole) (EDOTVBCz) comonomer was chemically synthesized and characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance, and carbon nuclear magnetic resonance spectroscopy. EDOTVBCz was electrocoated on glassy carbon electrode (GCE) in various initial molar concentrations ([EDOTVBCz]0?=?1.0, 1.5, 2.0, and 3.0) in 0.1 M lithium perchlorate (LiClO4)/acetonitrile (CH3CN). P(EDOTVBCz)/GCE was characterized by cyclic voltammetry, FTIR reflectance-attenuated total reflection spectroscopy, scanning electron microscopy–energy dispersive X-ray analysis, atomic force microscopy, and electrochemical impedance spectroscopy (EIS). EIS was used to determine the capacitive behaviors of modified GCE via Nyquist, Bode magnitude, Bode phase, and admittance plots. The highest low-frequency capacitance value was obtained as C LF?=?~2.35 mF cm?2 for [EDOTVBCz]0?=?3.0 mM. Double-layer capacitance of the polymer/electrolyte system was calculated as C dl?=?~2.78 mF cm?2 for [EDOTVBCz]0?=?1.0 and 3.0 mM. The maximum phase angle was obtained as θ?=?~76.7o for [EDOTVBCz]0?=?1.0, 1.5, 2.0, and 3.0 mM at the frequency of 20.6 Hz. AC impedance spectra of P(EDOTVBCz)/LiClO4/CH3CN was obtained by performing electrical equivalent circuit model of R(Q(R(CR))) with linear Kramers–Kronig test. Figure
SEM-EDX analysis of P(EDOTVBCz)/CFME EDX point analysis inset: SEM point analysis, [EDOTVBCz]0?=?3 mM. Chronoamperometric method of constant potential at 1.6 V, 300 s in 0.1 M LiClO4/CH3CN 相似文献
17.
Murat Güney Selçuk Eşsiz Arif Daştan Metin Balci Ottorino De Lucchi Ertan Şahin Fabrizio Fabris 《Helvetica chimica acta》2013,96(5):941-950
Stereoisomerically pure endo‐ and exo‐7‐halo‐7‐(trimethylstannyl)benzonorcar‐3‐enes (=endo‐ and exo‐(1‐halo‐1a,2,7,7a‐tetrahydro‐1H‐cyclopropa[b]naphthalen‐1‐yl)trimethylstannane) 4 and 6 were selectively obtained by lithium? tin or magnesium? tin transmetalation in good yields (Scheme 2 and 3). The reaction of these compounds with copper(I) thiophene‐2‐carboxylate (CuTC) produced in both cases the corresponding CS‐symmetric bicyclopropylidene (=cyclopropylidenecyclopropane) syn‐ 1 , a single diastereoisomer (Schemes 5 and 6). The structure of syn‐ 1 was undoubtedly elucidated by X‐ray single crystal diffraction. The coupling mechanism of the carbenoid cyclopropane is discussed (Scheme 7). 相似文献
18.
Gülşah Kalaycı Murat Belivermiş Önder Kılıç Sayhan Topcuoğlu Yavuz Çotuk 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):239-244
This study was carried out to better understand the biokinetics of radiocesium in clams living in sediment. The accumulation and depuration kinetics of 134Cs were investigated in the Manila clam (Ruditapes philippinarum) under controlled laboratory conditions. The concentration factor was found to be 3.0 for 134Cs in the whole body; however, the concentration factor in the soft part of the clams (12) was significantly higher than those in the whole body and shell (0.80). The depuration kinetics of the radionuclide were described by a two-component exponential model for the whole body. The biological half-lives in the fast and slow components were found to be 0.63 and 22.1 days, respectively. The depuration kinetics for 134Cs in the soft parts were described by a single-component exponential model with a resultant the biological half-life of 18.0 days. 相似文献
19.
Begüm Akduman Murat Uygun Esin Poyrazoğlu Çoban Deniz Aktaş Uygun Halil Bıyık Sinan Akgöl 《Applied biochemistry and biotechnology》2013,171(8):2285-2294
In this work, bacterial cellulose nanofibers were produced by using the Gluconacetobacter hansenii HE1 strain. These nanofibers were derivatized with dye affinity ligand Reactive Green 5, and these newly synthesized dye-attached nanofibers were used for affinity adsorption of urease. Reactive Green 5-attached nanofibers were characterized by Fourier transform infrared spectroscopy, SEM, and energy-dispersive x-ray spectroscopy analysis. Some adsorption conditions which significantly affect the adsorption efficiency were investigated. The maximum urease adsorption capacity was found to be 240 mg/g nanofiber in pH 6.0 and at room temperature. Dye-free plain nanofibers also used for studying nonspecific urease adsorption onto plain nanofibers and nonspecific adsorption were found to be negligible (3.5 mg/g nanofiber). Prepared dye-attached nanofibers can be used in five successive adsorption/desorption steps without any decrease in their urease adsorption capacity. The desorption rate of the adsorbed urease was found to be 98.9 %. The activity of the urease was also investigated, and it was found that free and desorbed urease from the dye-attached nanofibers showed similar specific activity. 相似文献
20.
Vibration analysis of cracked beams having linearly varying cross-sections both in thickness and width was investigated. A computer program using the finite element method has been written to find the dynamical characteristics (natural frequencies and mode shapes) of the cracked beam. The cracked section in the beam has been modeled by a massless spring whose flexibility depens on the local flexibility induced by the crack. The stiffness of spring has been derived from the linear elastic fracture mechanics theory as the inverse of the compliance matrix calculated using stress intensity factors and strain energy release rate expression. Some examples have been given to explain the proposed method and investigate the effects of the depth and location of cracks on the natural frequencies and mode shapes. The results of current study and those in the literature are compared and good agreements have been found. Consequently it is showed that proposed method is reliable and simple. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献