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81.
82.
Synthesis of Some Novel Norbornene‐Fused Pyridazines as Potent Inhibitors of Carbonic Anhydrase and Acetylcholinesterase 下载免费PDF全文
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
83.
Dibenzo[e,k]-2,3-bis(hydroxyimino)-1,4-dithia-7,10-diaza-2,3,8,9-tetrahydrocyclododecine (H2L) has been prepared from 1,2-bis(o-mercaptoanilino) ethane ( 4 ) and (E,E)-dichloroglyoxime. A mononuclear complex with a metal: ligand ratio of 1:2 has been isolated for cobalt(III). The CoIII complex of H2L has been prepared with L′ = 2,6-lutidine, and with a chlorine ion as axial ligands. In addition to that, the synthesis of a new cobalt complex which contains BF2+ bridges is achieved with the bis(E,E)-dioxime ligand. The trinuclear complex of this CoIII complex has been obtained by the reaction of BF2+ bridged CoIII complex with Pd[bis(benzonitrile)]Cl2. The structures of these complexes and (E,E)-dioxime were identified by using elemental analysis, 1H and 13C-NMR, IR and MS spectral data. 相似文献
84.
Mononuclear [Co(HL)2LCl)], [Co(LBF2)2LCl] or [Cu-(HL)2] H2L = {N,N-bis (4-N-phenylaza [15]crown-5)diaminoglyoxime} and a trinuclear, [Cu(L)2(CuL)2](NO3)2, complex of the ligand were synthesized and characterized. The mononuclear copper(II) species coordinates to two copper(II) ions through the deprotonated oximate oxygens to yield a trinuclear structure cis-bridged by the oximate groups, with 1,10-phenanthroline as an end-cap ligand. The terminal copper adopts an essentially planar configuration with the nitrogen atoms of H2L. The structure of the ligand and its complexes is proposed and formulated according to the elemental analyses, 1H- and 13C-n.m.r, i.r. and m.s. spectral data. 相似文献
85.
Kapou A Benetis NP Durdagi S Nikolaropoulos S Mavromoustakos T 《Journal of chemical information and modeling》2008,48(11):2254-2264
Thirty-eight antileukemic steroidal esters possessing conformationally flexible nitrogen mustards were studied, and the 3D QSAR/CoMFA and CoMSIA methodologies were applied in order to derive the correlation between their structure and the in vivo antileukemic activity. These compounds show significantly reduced toxicity and possibly increased bioavailability compared to free nitrogen mustards and therefore constitute potent antileukemic drugs. Both the CoMFA and CoMSIA studies gave similar results indicating that the steric effect and the hydrophobic/hydrophilic balance especially in the steroidal part of the molecules probably determined their bioactivity. Of paramount interest is the observation that the orientation of the alkylating part of the SMEs toward the surface of ring B of the steroidal skeleton was related with increased activity. Concerning the steroidal part, the presence of hydrophobic groups in rings B and D was found to be important for enhanced activity. Enhancement of antileukemic potency is further observed if hydrophilic/H-bond acceptor groups are present at the positions 7 and 17 of the steroidal skeleton. Leapfrog simulations provided novel compounds which lead our future synthetic endeavor for obtaining SMEs with optimum bioactivity. 相似文献
86.
This paper presents a quantitative risk assessment for design and development of a renewable energy system to support decision‐making among design alternatives. Throughout the decision‐making phases, resources are allocated among exploration and exploitation tasks to manage the uncertainties in design parameters and to adapt designs to new information for enhanced performance. The resource allocation problem is formulated as a sequential decision feedback loop for a quantitative analysis of exploration and exploitation trade‐offs. We support decision‐making by tracking the evolution of uncertainties, the sensitivity of design alternatives to the uncertainties, and the performance, reliability, and robustness of each design. This is achieved by analyzing the uncertainties in the wind resource, the turbine performance and operation, and the models that define the power curve and wake deficiency. Comparison of the performance, reliability, and robustness of aligned and staggered turbine layouts before and after wind assessment experiments aids in improving micro‐siting decisions. The results demonstrate that design decisions can be supported by efficiently allocating resources towards improved estimates of achievable design objectives and by quantitatively assessing the risk in meeting those objectives. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
87.
88.
Serbest Kerim Karaböcek Serdar Değirmencioğlu İsmail Güner Saadettin Kormali Fatma 《Transition Metal Chemistry》2001,26(4-5):375-379
A new ligand incorporating a dioxime moiety, 3-{2-[2-(2-hydroxyimino-1-methylpropylideneamino)ethylamino]ethylimino}butan-2-one oxime, (H2mdo), has been synthesized and its mono-, di- and trinuclear copper(II), and hetero-dinuclear copper(II)–manganese(II) complexes have been prepared and characterized by elemental analyses, magnetic moments, 1H- and 13C-n.m.r., i.r. and mass spectral studies. A mononuclear copper(II) complex of H2mdo was found to have a 1:1 metal:ligand ratio. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N); the data support the proposed structure of H2mdo and its complexes. 相似文献
89.
The constitutive theories intended to quantitatively account for the complicated material response exhibited by polymers include, in general, adjustable material parameters. These must be identified from experimental data obtained from the material under consideration. This contribution presents the complete procedure studying the behavior of polymers at large strains in three basic steps: i) Accomplishment of homogeneous and 3-D inhomogeneous experiments under different deformation conditions. ii) Identification of the material parameters of a constitutive model by means of gradient–based optimization methods with respect to the homogeneous experimental data. iii) Validation of the identified material parameters by comparing 3-D FE simulations to the inhomogeneous experimental data. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
90.
Reaching a control on the mesoscopic morphology and internal molecular arrangement of cyanine aggregates is an important step for realization of devices with tailor-made optical properties. Despite a wealth of research, understanding of the relationship between molecular organization, excitonic states and dynamics of aggregates is still preliminary. To this end, we have employed polarized absorption spectroscopy to investigate the relationship between internal molecular organization and excitonic states of J-aggregates in 1,1′,3,3′tetraethyl-5,5′,6,6′-tetrachlorobenzimidazolocarbocyanine (TTBC) thin films in poly-vinyl alcohol (PVA). Angular dependence of the UV–vis spectra has been measured at 11 different orientations between the electric field polarization and the macroscopic alignment axis. Aggregate spectral response consisted of an asymmetrically split Davydov pair of bands exhibiting opposite polarization: an H-band (505 nm, Lorentzian-like, polarized along the macroscopic film axis) and a J-band (594 nm, one-dimensional J-aggregate like band shape, polarized perpendicular to the macroscopic film axis). The polarized absorption observations were found to be consistent with a herringbone model for which the internal molecular arrangement, the excited state structure and dynamics have recently been detailed by us upon interpretation of isotropic absorption data in ionic aqueous solution. 相似文献