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51.
Synthesis of Some Novel Norbornene‐Fused Pyridazines as Potent Inhibitors of Carbonic Anhydrase and Acetylcholinesterase
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Ramazan Kocak Esra Turan Akın Pınar Kalın Oktay Talaz Nurullah Saracoglu Arif Dastan Ilhami Gülcin Serdar Durdagi 《Journal of heterocyclic chemistry》2016,53(6):2049-2056
The reaction of benzocyclic norbornene derivatives with tetrazines provided the 1,3‐dihydropyridazine derivatives as a single product. The dihydropyridazine derivatives have been dehydrogenated with phenyliodine bis(trifluoroacetate) to yield the corresponding pyridazines in a high yield. Two stable diazines, primary product of corresponding 1,4‐dihydropyridazine, were also isolated. Structures were then determined by 1H‐NMR, and 13C‐NMR beside to elemental analyses. The novel pyridazine derivatives ( 8 , 9 ) efficiently inhibited the cytosolic human carbonic anhydrase isoenzymes I and II (hCA I and II). In addition, these novel pyridazine derivatives ( 8 , 9 ) were evaluated for their in vitro acetylcholinesterase inhibitory activity. Ligand–receptor interactions are tested using molecular docking simulations. Obtained docking scores are in good agreement with in vitro results. 相似文献
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Eylem Turan Adem Zengi̇n Tuncer Caykara 《Journal of polymer science. Part A, Polymer chemistry》2011,49(23):5116-5123
The single‐electron transfer living radical polymerization (SET‐LRP) method in the presence of chain transfer agent was used to synthesize poly(N‐isopropylacrylamide) [poly(NIPAM)] with a low molecular weight and a low polydispersity index. This was achieved using Cu(I)/2,2′‐bipyridine as the catalyst, 2‐bromopropionyl bromide as the initiator, 2‐mercaptoethanol as the chain transfer agent (TH), and N,N‐dimethylformamide (DMF) as the solvent at 90 °C. The copper nanoparticles with diameters of 16 ± 3 nm were obtained in situ by the disproportionation of Cu(I) to Cu(0) and Cu(II) species in DMF at 22 °C for 24 h. The molecular weights of poly(NIPAM) produced were significantly higher than the theoretical values, and the polydispersities were less than 1.18. The chain transfer constant (Ctr) was found to be 0.051. Although the kinetic analysis of SET‐LRP in the presence of TH corroborated the characteristics of controlled/living polymerization with pseudo‐first‐order kinetic behavior, the polymerization also exhibited a retardation period (k > ktr). The influence of molecular weight on lower critical solution temperature (LCST) was investigated by refractometry. Our experimental results explicitly elucidate that the LCST values increase slightly with decreasing molecular weight. Reversibility of solubility and collapse in response to temperature well correlated with increased molecular weight of poly(NIPAM). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
54.
Numerical simulation of steady state operation of a vertical two phase closed thermosyphon is performed using the two-fluid methodology within Eulerian multiphase domain. A full scale axi-symmetric model is developed for computational fluid dynamics simulation of thermosyphon using ANSYS/FLUENT 13.0. The effects of evaporation, condensation and interfacial heat and mass transfer are taken into account within the whole domain. Cooling water jacket is also modelled along with the wall of thermosyphon to simulate the effect of conjugate heat transfer between the wall and fluid phase. The results obtained are presented and compared with available experimental investigations for a similar thermosyphon. It is established that two-fluid methodology can be used effectively for the purpose of simulation of two phase system like a typical thermosyphon. 相似文献
55.
A new water-soluble, highly fluorogenic 3-formylBODIPY dye that enables the sensing of SO2 derivatives in aqueous buffers and cancer cells is reported. The quaternary ammonium group appended through the meso-position of the BODIPY dye ensures water solubility. The probe exhibits high specificity for cytosolic (bi)sulfites and fluoresces brightly in human lung adenocarcinoma cells (A549). 相似文献
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Qiang Lai Akif Akgul Metin Varan Jacques Kengne Alper Turan Erguzel 《Chinese Journal of Physics (Taipei)》2018,56(6):2837-2851
This paper reports a new four-dimensional chaotic system consisting of an exponential nonlinear term, two quadratic nonlinear terms and five linear terms. The system has only one equilibrium and performs stability, periodicity and chaos with the variation of the parameters. It losses its stability with the occurrence of Hopf bifurcation and goes into chaos via period-doubling bifurcation. One more interesting feature of the system is that it can generate multiple coexisting attractors for different initial conditions, such as two strange attractors with one limit cycle, one strange attractor with two limit cycles, etc. The dynamic properties of the system are presented by numerical simulation includes bifurcation diagrams, Lyapunov exponent spectrum and phase portraits. An electronic circuit is constructed to implement the chaotic attractor of the system. Based on the linear quadratic regulator (LQR) method, the synchronization control of the system is investigated. 相似文献
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The influence of initial tension or compression along cracks on the stress intensity factor (SIF) at crack tips under the action of additional normal forces on crack edges is studied for infinite bodies. A strip made of a composite material is considered. The strip ends are simply supported, and the strip contains a crack whose edges are parallel to its face planes. The strip is first stretched or compressed along crack edges, and then additional uniformly distributed normal forces are applied to the crack edges. The influence of the initial tension (compression) on the SIF caused by the additional normal forces is studied. The corresponding boundary-value problems are modelled with the use of the three-dimensional linearized theory of elasticity. All the investigations are carried out numerically by employing the finite-element method. The values of SIF are calculated by the energy release method. 相似文献
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A new high‐performance blue to transmissive electrochromic material and use of silver nanowire network electrodes as substrates
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Janset Turan Ece Alpugan Serife Ozdemir Hacioglu Levent Toppare Ali Cirpan Husnu Emrah Unalan Gorkem Gunbas 《Journal of polymer science. Part A, Polymer chemistry》2017,55(10):1680-1686
Synthesis of a novel, high‐performance blue to transmissive switching electrochromic material is described. The polymer (P1) was prepared by both electrochemical ( P1E ) and chemical ( P1C ) means from the corresponding monomer. The electrochemically synthesized polymer ( P1E ) revealed 64% optical contrast change (on ITO) in the visible region and very fast switching times of 0.32 s (coloration) and 0.90 s (bleaching). On the other hand, the chemically synthesized, solution processable polymer ( P1C ) also showed a high optical contrast value (49%, on ITO) with very fast switching times of 0.86 s for coloration and 0.57 s for bleaching. These high optical contrast values coupled with fast switching times place these materials along with high‐performance blue to transmissive electrochromic polymers. Significantly, these improved characteristics were achieved by side chain engineering of a known, inferior blue to transmissive polymer, PBEBT. Towards fabrication of flexible electrochromic devices, the performance of P1C was also tested on silver nanowire network electrodes. Even though the full potential of the material could not be demonstrated, a good optical contrast of 24% was achieved using these electrodes. Under the same potential range allowed by silver nanowire network electrodes, P1C on ITO showed an optical contrast of 30%. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1680–1686 相似文献