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421.
422.
Yousry A. Ammar Mohsen M. Aly Abd Allah G. Al‐Sehemi Mohamed A. Salem Mohamed S. A. El‐Gaby 《中国化学会会志》2009,56(5):1064-1071
Novel 5‐aminopyrazole and pyrazolo[1,5‐a]pyrimidine derivatives have been synthesized from the readily accessible cyanoacetanilide derivative ( 2 ). 相似文献
423.
Ahmed Elkamhawy Usama M. Ammar Sora Paik Magda H. Abdellattif Mohamed H. Elsherbeny Kyeong Lee Eun Joo Roh 《Molecules (Basel, Switzerland)》2021,26(17)
Recently, multitargeted drugs are considered a potential approach in treating cancer. In this study, twelve in-house indole-based derivatives were preliminary evaluated for their inhibitory activities over VEGFR-2, CDK-1/cyclin B and HER-2. Compound 15l showed the most inhibitory activities among the tested derivatives over CDK-1/cyclin B and HER-2. Compound 15l was tested for its selectivity in a small kinase panel. It showed dual selectivity for CDK-1/cyclin B and HER-2. Moreover, in vitro cytotoxicity assay was assessed for the selected series against nine NCI cell lines. Compound 15l showed the most potent inhibitory activities among the tested compounds. A deep in silico molecular docking study was conducted for compound 15l to identify the possible binding modes into CDK-1/cyclin B and HER-2. The docking results revealed that compound 15l displayed interesting binding modes with the key amino acids in the binding sites of both kinases. In vitro and in silico studies demonstrate the indole-based derivative 15l as a selective dual CDK-1 and HER-2 inhibitor. This emphasizes a new challenge in drug development strategies and signals a significant milestone for further structural and molecular optimization of these indole-based derivatives in order to achieve a drug-like property. 相似文献
424.
Sidra Khalid Muhammad Ammar Zahid Hussain Ali Yeong S. Kim Salman Khan 《BMC neuroscience》2018,19(1):74
Background
Alzheimer’s disease (AD) is a primary cause of dementia in ageing population affecting more than 35 million people around the globe. It is a chronic neurodegenerative disease caused by defected folding and aggregation of amyloid beta (Aβ) protein. Aβ is formed by the cleavage of membrane embedded amyloid precursor protein (APP) by using enzyme ‘transmembrane aspartyl protease, β-secretase’. Inhibition of β-secretase is a viable strategy to prevent neurotoxicity in AD. Another strategy in the treatment of AD is inhibition of acetylcholinesterase. This inhibition reduces the degradation of acetylcholine and temporarily restores the cholinergic function of neurons and improves cognitive function. Monoamine oxidase and higher glutamate levels are also found to be linked with Aβ peptide related oxidative stress. Oxidative stress leads to reduced activity of glutamate synthase resulting in significantly higher level of glutamate in brain. The aim of this study is to perform in silico screening of a virtual library of biaryl scaffold containing compounds potentially used for the treatment of AD. Screening was done against the primary targets of AD therapeutics, acetylcholinesterase, β-secretase (BACE1), Monoamine oxidases (MAO) and N-Methyl-D-aspartate (NMDA) receptor. Compounds were screened for their inhibitory potential by employing molecular docking approach using AutoDock vina. Binding energy scores were embodied in the heatmap to display varies strengths of interactions of the ligands targeting AD.Results
Several ligands showed notable interaction with at least two targets, but the strong interaction with all the targets is shown by very few ligands. The pharmacokinetics of the interacting ligands was also predicted. The interacting ligands have good drug-likeness and brain availability essential for drugs with intracranial targets.Conclusion
These results suggest that biaryl scaffold may be pliable to drug development for neuroprotection in AD and that the synthesis of further analogues to optimize these properties should be considered.425.
Miroslav Grmela Guillaume Maîtrejean Francisco Chinesta Amine Ammar 《Rheologica Acta》2013,52(6):557-577
Smoluchowski kinetic equation governing the time evolution of the pair correlation function of rigid sphericalparticles suspended in a Newtonian fluid is extended to include particle migration. The extended kinetic equation takes into account three types of forces acting on the suspended particles: a direct force generated by an interparticle potential, hydrodynamic force mediated by the host fluid, and the Faxén-type forces bringing about the across-the-streamline particle migration. For suspensions subjected to externally imposed flows, the kinetic equation is solved numerically by the proper generalized decomposition method. The imposed flow investigated inthe numerical illustrations is the Poiseuille flow. Numerical solutions provide the morphology (the pair correlation function), the rheology (the stress tensor), and the particle migration. 相似文献
426.
Calorimetric, magnetic and X-ray diffraction measurements have been used to study the magnetic susceptibility and thermal stability of Co80ErxB20−x with (0 ? x ? 4) amorphous ribbons. The compounds are found to crystallize in Co2B and β-Co, after precipitation of the tetragonal Co3B phase. The addition of erbium shifts up the crystallization temperature leading to the increase in the stability of the amorphous state. Magnetic susceptibility measurements show that the addition of erbium increases the Curie temperature and induces noncollinear magnetic behavior. This latter fact is explained on the basis of random local magnetic anisotropy related to the rare earth atoms in amorphous materials. 相似文献
427.
Four new complexes of Au(III), Pd(II), Ni(II), and Cu(II) ions were synthesized, derived from a novel heterocyclic ligand (L) that has both triazole and tetrazole rings. The ligand synthesis was through successive steps to achieve both heterocyclic rings. The synthesized compounds were characterized using conventional techniques like infrared, ultra violet—visible and proton/carbon nuclear magnetic resonance spectroscopy, metal and thermal analyses, and molar conductivity. All complexes were suggested to have square planar geometry, gold, nickel, and palladium complexes were salts while copper neutral complexes have the chemical formulas; [AuL2]Cl.2H2O, [PdL2]Cl2.2H2O, [NiL2]Cl2.2H2O, and [CuL2]. The cytotoxic effect was studied on breast cancer cell line (MCF‐7 cell line) at different concentrations by using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay method, for the ligand (L) and complexes. The results showed that gold(III) and nickel(II) complexes have the highest cytotoxicity among all compounds against cancer cell lines. 相似文献
428.
Multivalent interactions in which multiple ligands on one object bind to multiple receptors on another are commonly found in natural biological systems. In addition, these interactions can lead to increased strength and selectivity when compared to the corresponding monovalent interaction. These attributes have also guided the design of synthetic multivalent ligands to control biological interactions. This review will highlight the recent literature describing the use of multivalent ligand display in the design of vaccines, immunomodulators, cell signaling effectors, and vehicles for targeted drug delivery. 相似文献
429.
Brandenburg G Ershov A Kim DY Wilson R Benslama K Eisenstein BI Ernst J Gollin GD Hans RM Karliner I Lowrey N Marsh MA Plager C Sedlack C Selen M Thaler JJ Williams J Edwards KW Ammar R Besson D Zhao X Anderson S Frolov VV Kubota Y Lee SJ Li SZ Poling R Smith A Stepaniak CJ Urheim J Ahmed S Alam MS Jian L Saleem M Wappler F Eckhart E Gan KK Gwon C Hart T Honscheid K Hufnagel D Kagan H Kass R Pedlar TK Thayer JB Von Toerne E Wilksen T Zoeller MM Richichi SJ Severini H Skubic P Dytman SA Nam S 《Physical review letters》2002,89(22):222001
Using 13.53 fb(-1) of CLEO data, we have measured the ratios of the branching fractions R(+)(e),R(+)(mu) and the combined branching fraction ratio R(+)(l), defined by R(+)(l)=[B(D+-->K(*0)l(+)nu(l))]/[B(D+-->K-pi(+)pi(+))]. We find R(+)(e)=0.74+/-0.04+/-0.05, R(+)(mu)=0.72+/-0.10+/-0.05, and R(+)(l)=0.74+/-0.04+/-0.05, where the first and second errors are statistical and systematic, respectively. The known branching fraction B(D+-->K-pi(+)pi(+)) leads to B(D+-->K(*0)e(+)nu(e))=(6.7+/-0.4+/-0.5+/-0.4)%, B(D+-->K(*0)mu(+)nu(mu))=(6.5+/-0.9+/-0.5+/-0.4)%, and B(D+-->K(*0)l(+)nu(l))=(6.7+/-0.4+/-0.5+/-0.4)%, where the third error is due to the uncertainty in B(D+-->K-pi(+)pi(+)). 相似文献
430.
P. Foggi P. Bartolini M. Bellini M.G. Giorgini A. Morresi P. Sassi R.S. Cataliotti 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(2):143-151
The relaxation dynamics of pure acetonitrile isotopomers has been investigated in the temperature range 8 to 75 °
C. The overall response of the liquid is measured either recording directly the decay of the optical Kerr signal with heterodyne
detection (OHD-OKE) and Fourier transforming the depolarized Rayleigh scattering spectra (DRS). The OHD-OKE signals show a
decay that can be described by a bi-exponential law. At some temperatures, stressing to a maximum level the sensitivity of
the OHD-OKE experimental set-up, a damped oscillation is observed on top of the fast decay component. The two techniques provide
same results with a high level of reproducibility, as far as the slow component is concerned. This latter is described by
an exponential law with the time constants ranging in the interval 2.0 to 0.85 ps in the light and approximately in the same
interval in the deuterated molecule. The decays are, at all temperatures, well reproduced by the extended diffusion J-model. The fast component, better observed with the OHD-OKE experiments in a restricted temperature range, has time constants
ranging from 550 to 350 fs. After the subtraction of the curve due to the slower decay component, the data have also been
analyzed by Fourier transforming the fast part of the decay. The spectrum then consists of a broad (approximately 80 cm-1 wide) band centered at 50 cm-1. This band is interpreted as the manifestation of intermolecular vibrational motions.
Received 21 July 2002 Published online 1st October 2002
RID="a"
ID="a"e-mail: foggi@colonnello.lens.unifi.it 相似文献