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61.
Microtubules are tube-shaped, filamentous and cytoskeletal proteins that are essential in all eukaryotic cells. Microtubule is an attractive and promising target for anticancer agents. In this study, three-dimensional quantitative structure activity relationships (3D-QSAR) including comparative molecular field analysis, CoMFA, and comparative molecular similarity indices analysis, CoMSIA, were performed on a set of 45 (E)-N-Aryl-2-ethene-sulfonamide analogues as microtubule-targeted anti-prostate cancer agents. Automated grid potential analysis, AutoGPA module in Molecular Operating Environment 2009.10 (MOE) as a new 3D-QSAR approach with the pharmacophore-based alignment was carried out on the same dataset. AutoGPA-based 3D-QSAR model yielded better prediction parameters than CoMFA and CoMSIA. Based on the contour maps generated from the models, some key features were identified in (E)-N-Aryl-2-arylethene-sulfonamide analogues that were responsible for the anti-cancer activity. Virtual screening was performed based on pharmacophore modeling and molecular docking to identify the new inhibitors from ZINC database. Seven top ranked compounds were found based on Gold score fitness function. In silico ADMET studies were performed on compounds retrieved from virtual screening in compliance with the standard ranges. 相似文献
62.
Mattia Perrone 《Journal of Functional Analysis》2009,256(11):3471-3489
We study Haagerup inequality for radial functions on uniform lattices in semisimple Lie groups, with respect to Riemannian metrics and, in some case, to word metrics. In particular we extend the Swiatkowski-Valette results to any lattice acting properly and essentially transitively on classical buildings. 相似文献
63.
64.
We have developed a new automatic sample-preparation robot system with use of the volumetric-weighing method. In this system, slurries, aqueous solutions, and other wet reagents are employed as starting materials and 64 (8×8) samples at the maximum are prepared on a library plate of 35 mm × 35 mm size. Volumetric-weighing and mixing of the starting materials and distributing reaction mixtures to the library plate are automatically performed by computer-controlled mechanisms with an easy-to-use programming software interface. While this robot is designed in terms of space saving and portability, it is able to equip with an atmosphere-controlled furnace to sinter the samples on the library plate. Typical preparation time for a library plate of 36 (6×6) samples is less than 40 min. This robot system is promising in enhancing throughput of wet-chemically synthesized materials researches. 相似文献
65.
层状的过渡金属硫化物及其衍生物在许多领域内有着广泛的应用前景. 具体应用包括催化、陶瓷、润滑、能量储存、半导体、电子与光学器件. 该文报道了作者最近用固体核磁共振光谱的方法来表征几种有代表性的过渡金属硫化物(MS2: M=Zr, Ti, W, Mo和Ta)的结果. 并在不同的磁场强度下(21.1、14.1、9.4 T)成功地获取了33S, 47/49Ti,91Zr,95Mo 在天然丰度下的固体核磁共振光谱. 为了帮助解释实验结果,同时还进行了量子化学计算. 实验及理论计算的结果都表明33S, 47/49Ti, 91Zr, 95Mo 的固体核磁共振参数对于这些核的局部几何与电子环境非常敏感. 相似文献
66.
Paolo Lipparini 《Archive for Mathematical Logic》1996,35(2):63-87
We develop a method for extending results about ultrafilters into a more general setting. In this paper we shall be mainly concerned with applications to cardinality logics. For example, assumingV=L, Gödel's Axiom of Constructibility, we prove that if > then the logic with the quantifier there exist many is (,)-compact if and only if either is weakly compact or is singular of cofinality<. As a corollary, for every infinite cardinals and , there exists a (,)-compact non-(,)-compact logic if and only if either < orcf<cf or < is weakly compact.Counterexamples are given showing that the above statements may fail, ifV=L is not assumed.However, without special assumptions, analogous results are obtained for the stronger notion of [,]-compactness. 相似文献
67.
The role of the Mg2+ cation on huperzine molecule binding (drugs used for Alzheimer disease) on human serum albumin (HSA) was studied by affinity chromatography. The thermodynamic data corresponding to this binding were determined for a wide range of Mg2+ concentrations (x). For each solute, the huperzine binding on HSA was divided into two Mg2+ concentration regions. For a low x value, below xc (1.2 mM), the binding decrease with x. For x above xc the hydrophobic effect and van der Waals interactions between the huperzine molecule and the HSA implied a decrease in its binding. These results showed that for patients with Alzheimer disease, an Mg2+ supplementation during treatment with these huperzine molecules can increase the active pharmacological molecule concentration. 相似文献
68.
M. Montazerozohori S.A. Musavi A. Masoudi-asl H. Mohammadi R. Naghiha A. Assoud 《Arabian Journal of Chemistry》2019,12(7):1463-1473
Three new four coordinated zinc(II) complexes have been synthesized and characterized by IR, UV, elemental analysis, 1H and 13C NMR and X-ray single crystal analysis. The elemental analyses of the complexes are in agreement with the general formula of ZnLX2 wherein L = Schiff base ligand and X = Cl?, Br? and I?. Low molar conductivities in DMF indicated non-electrolyte character of all complexes. Spectroscopic studies well confirmed the coordination via azomethine nitrogens of the ligand to zinc ion. The single crystal X-ray analysis shows that ZnLBr2 crystallizes in the triclinic crystal system with space group . It contains two crystallographically independent molecules noted as A and B, with both Zn1A and Zn1B being almost in perfect tetrahedral environments (τ4 = 0.94 for Zn1A and τ4 = 0.93 for Zn1B). A detailed structural analysis shows that there are three non-classical hydrogen bondings of C–H…Br in the structure. Various C–H…π and C–H…Br interactions play an important role in stabilizing the molecular structure and then give rise to a 3D supramolecular structure of the ZnLBr2 complex. After characterization, the Schiff base and its complexes were screened in vitro for their antibacterial and antifungal activities by disk diffusion technique. Also the ability of the complexes for DNA cleavage was studied by agarose gel electrophoresis method. Finally, thermal behavior of the complexes has been studied by thermo-gravimetry and then some activation kinetics parameters of decomposition steps were evaluated based on TG/DTG plots. 相似文献
69.
Antonio?ArcelliEmail author Daniele?Balducci Alessandro?Grandi Gianni?Porzi Monica?Sandri Sergio?Sandri 《Monatshefte für Chemie / Chemical Monthly》2004,135(8):951-958
Summary. A series of chiral 1,4-morpholine-2,5-dione derivatives were synthesized. These substrates behave as non competitive inhibitors against -glucosidase showing a moderate inhibition (Ki< 0.8mM) and were found inactive towards -glucosidase. 相似文献
70.
Four trinuclear molybdenum(tungsten)-sulfur carbonyl cluster compounds, [Et4N]2[(OC)4Mo-S2MoS2Mo(CO)4] (1), [Et4N]2[(OC)4WS2WS2W(CO)4] (2), [Et4N]2[(OC)4MoS2WS2Mo(CO)4] (3), [Et4N]2[(OC)4WS2MoS2W(CO)4] (4) have been prepared by both reaction of [M(CO)4(S2CNEt2)]− with M′S42− in MeOH and reaction of MeCN solution of M(CO)6 with M′S42− in MeOH (M=Mo, W; M′=Mo, W). These complexes has been characterized by routine elemental analysis and spectroscopy and the structures of 1 and 3 have been determined by X-ray crystallography. The structure study reveals that the anion of 3 contains a heteronuclear Mo–W–S trimetallic core, [MoS2WS2Mo]2−, consisting of two perpendicular rhombic MoS2W units sharing a tungsten atom. The Mo–W bond distances are 3.028(2) and 3.031(2) Å and the Mo–W–Mo angle is 176.04(5)°. The average bond lengths of W–S and Mo–S are 2.21 and 2.54 Å, respectively. The X-ray, structure, IR, CV (cyclic voltammetry) and 95 Mo NMR studies on these four cluster complexes indicated that these cluster complexes possess wide separated oxidation states of metal atoms and exhibit the charge transfer, ML→MHS4 (ML represents a low-valance metal atom and MH a high valence metal atom), between the two different valence metallic centers in the cluster complexes. It has been found that the charge transfer, ML→MHS4, in the complexes are: 1>4, 3>2, 1>3, 4>2, 1>2 and 34 implying the electron-donation ability of low-valence metal atoms in the complexes is Mo0>W0 and the electron-accepted ability of the high valence metal atoms in the complexes is MoVI>WVI. 相似文献