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81.
Myers MC Wang J Iera JA Bang JK Hara T Saito S Zambetti GP Appella DH 《Journal of the American Chemical Society》2005,127(17):6152-6153
Cells that express mutant p53 derived from cancers are selectively killed by a new class of small organic molecules. The protein p53 is recognized as one of the most important guardians in the body that prevents tumor development. Mutant forms of p53 are present in approximately 50% of all human cancers. Molecules that selectively kill cells expressing mutant p53 could become important chemotherapeutic agents. Our research focuses on developing a synthetically accessible class of molecules that can be easily modified to examine structural activity relationships and mechanism of biological activity or to optimize for anticancer activity. In this communication, a new class of molecules that selectively arrests growth of cells expressing two forms of mutant p53 is described. Synthetic routes to these compounds are also presented. 相似文献
82.
Four Metal Complexes Based on Bulky Imidazole Ligands: Solvothermal Syntheses,Crystal Structures,and Fluorescence Properties 下载免费PDF全文
Xue Zhang Sai Li Yue‐Jiao He Tong Han Xiao‐Ling Wang Bang Chen Kang‐Yu Zou Zuo‐Xi Li 《无机化学与普通化学杂志》2015,641(11):1874-1880
In order to explore the influences of (de‐)protonation of the imidazole ring on the structural diversity of the resulting complexes, the imidazole‐based ligands 4, 5‐diphenylimidazole (Hdpi) and 1H‐phenanthro[9, 10‐d]imidazole (Hpi) were utilized as bulky building blocks to construct four complexes by solvothermal reactions, i.e. [Ag(Hdpi)2](NO3) · (H2O) ( 1 ), [Cu(dpi)]∞ ( 2 ), [Cu(Hpi)(NO3)]∞ ( 3 ), and [(H2pi)(NO3)] · H2O ( 4 ). In complex 1 , two Hdpi ligands adopt a monodentate pattern and coordinate with one AgI ion to form a mononuclear unit, which is further connected by hydrogen bonds into a 1D supramolecular helix. The deprotonated dpi ligand of 2 acts in bidentate mode, and bridges CuI ions to afford a 1D chain. In 3 , the NO3– ion, acts as a monodentate bridging ligand and joins CuI ions to generate a 1D chain. The Hpi ligand employs a monodentate mode to bond with CuI ions of the 1D chain. 4 is protonated and two H2pi nitrogen atoms are free of coordination. Interestingly, hydrogen bonds among the NO3– ion, the H2pi ligand, and the water molecule yield a macro ring R44(14). The resulting structural diversity reveals that the (de‐)protonation of imidazole ring directly steers the coordination number of ligand, and thus causes a significant effect on the structure, especially the dimensionality. Furthermore, the solid‐state fluorescence properties of the free ligands and compounds 1 – 4 were studied at room temperature. 相似文献
83.
Polarization labeling spectroscopy is applied to study the excited E(4)1Σ+ state of NaLi in the energy range 25 850-27 750 cm−1 above the bottom of the ground state. The potential curve of the E state is constructed using the Inverted Perturbation Approach method. 相似文献
84.
以二乙烯苯和双丙烯酸多缩乙二醇酯为交联剂、聚醋酸乙烯酯(PVAc)或它与醋酸丁酯(BAC)的混合物为致孔剂、BPO为引发剂,用悬浮聚合随后水解的方法制得了部分水解聚(丙烯酸甲酯-醋酸乙烯酯-甲基丙烯酸甲酯)[HP(MA-VAc-MMA)]多孔载体,研究了PVAc及(PVAc+BAC)用量、分子量及混合比对HP(MA-VAc-MMA)孔结构的影响。结果表明,当PVAc的M>2.5×105,PVAc/BAC为2.3,用量为10~20%时,可制得孔隙率较高,孔径分布较窄,孔表面积较大的多孔载体。这种载体适用于微生物固定化。 相似文献
85.
Soo‐Na Ahn Hwa‐Jeong Lee Bang‐Jun Kim Loon‐Seng Tan Jong‐Beom Baek 《Journal of polymer science. Part A, Polymer chemistry》2008,46(22):7473-7482
Short length vapor‐grown carbon nanofibers (VGCNFs) were functionalized with 4‐aminobenzoic acid in polyphosphoric acid/phosphorous phentoxide medium via “direct” Friedel‐Crafts acylation reaction to afford aminobenzoyl‐functionalized VGCNFs (AF‐VGCNFs). The AF‐VGCNFs as a cocuring agent were mixed with epoxy resin by simple mechanical stirring in methanol which was added to help efficient mixing. After evaporation of methanol, 4,4′‐methylenedianiline as a curing agent was added to the mixture, which was then cured at elevated temperatures. The resultant composites displayed uniform dispersion of AF‐VGCNFs into cured epoxy matrix. During curing process, the amine functionalities on AF‐VGCNF together with 4,4′‐methylenedianiline were expected to be involved in covalent attachment to the epoxy resin. As a result, both tensile modulus and strength of the composites were improved when compared with those of pure epoxy resin. Thus, the AF‐VGCNFs play a role as an outstanding functional additive, which could resolve both dispersion and interfacial adhesion issues at the same time by functionalization of VGCNFs and covalent bonding between the additive and matrix, respectively. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7473–7482, 2008 相似文献
86.
87.
The total binding energy of nuclei is determined by means of many-body field theory. The problem is then reduced to finding the energy-dependent average potential (mass operator) and solving the single-particle equations of motion. Such a potential can be established phenomenologically by using data on low excitations and reactions knocking out nucleons from deep “hole” levels. Calculations of the total binding energy of the nuclei 16O, 40Ca and 58Ni with this potential are in satisfactory agreement with experiment. 相似文献
88.
Ha Huy Bang 《International Journal of Theoretical Physics》1996,35(4):747-753
Generalized deformed commutation relations for a single-mode para-Bose oscillator are constructed. The connection of generalized
deformed para-Bose oscillators with para-Bose oscillators is determined. From these, the energy spectrum of generalized deformed
para-Bose oscillators and the coherent states of the annihilation operators are discussed.
On leave from Department of Physics, Hanoi National University, 90 Nguyen Trai, Hanoi, Vietnam. 相似文献
89.
J. M. Bang V. V. Flambaum J. M. Hansteen 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(4):431-432
Attention is drawn to a mechanism ofe + e ? pair production which may lead to peaks in the energy distribution of the pairs. 相似文献
90.