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91.
A simple and convenient method for the aromatization of Hantzsch 1,4-dihydropyridines to the corresponding pyridines is achieved via combination of aluminum or ferric nitrates and silica sulfuric acid as environmentally friendly and novel oxidizing media. This oxidation was carried out in dichloromethane under heterogeneous conditions with good to excellent yields. 相似文献
92.
Asymmetric total synthesis of the sex pheromones of Japanese beetle and currant stem girdler, (R)‐japonilure (1) and (4R,9Z)‐9‐octadecen‐4‐olide (2), has been achieved. 相似文献
93.
A practical protocol was disclosed for the nickel-catalyzed C-alkylation of 9-fluorenone hydrazone with alcohols using t-BuOK as the base, and 9-monoalkylated fluorene derivatives were obtained in good yields under the benign conditions. 相似文献
94.
Samantha Jenkins 《International journal of quantum chemistry》2013,113(11):1603-1608
The need to make more quantitative use of the total electronic charge density distribution is demonstrated in this short perspective. This is framed in the perspective of the ground breaking early work of Bader and coworkers, along with mathematicians who captured the essential nature of a molecule in a suitably compact form in real space. We see that this simple form is the Poincaré–Hopf relation for molecules and clusters and the Euler–Hopf relation in solids. Thom's theory of elementary catastrophes combined with the Poincaré–Hopf relation provides the inspiration for the new quantum topology. An alternative use of the Poincaré–Hopf relation, molecular recognition, is discussed. Quantum topology is then used to create a topology phase diagram for both molecules and solids. The author adds their perspectives of the huge potential of the quantum topology approach by demonstrating the ease with which new theoretical ideas can be generated. © 2013 Wiley Periodicals, Inc. 相似文献
95.
A Beckmann Rearrangement/Friedel-Crafts strategy was utilized to prepare 5-amidotetralones in high yield. 相似文献
96.
Approximation properties for solutions to non‐Lipschitz stochastic differential equations with Lévy noise 下载免费PDF全文
In this paper, we consider the non‐Lipschitz stochastic differential equations and stochastic functional differential equations with delays driven by Lévy noise, and the approximation theorems for the solutions to these two kinds of equations will be proposed respectively. Non‐Lipschitz condition is much weaker condition than the Lipschitz one. The simplified equations will be defined to make its solutions converge to that of the corresponding original equations both in the sense of mean square and probability, which constitute the approximation theorems. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
97.
Hyeonbae Kang Hyundae Lee Mikyoung Lim 《Mathematical Methods in the Applied Sciences》2015,38(9):1847-1854
We present a new systematic method to compute the Riemann mapping from the outside of the unit disc to the outside of a simply connected domain. We derive explicit relations between the coefficients of the Riemann mapping and the generalized polarization tensors associated with the domain. Because the generalized polarization tensors can be computed numerically, we are able to compute the coefficients of the Riemann mapping using these relations. Effectiveness of the method is validated by numerical examples. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
98.
J. Morais M. A. Pérez‐de la Rosa 《Mathematical Methods in the Applied Sciences》2015,38(17):4365-4387
Over the past few years, considerable attention has been given to the role played by the Lamé's Wave Functions (LWFs) in various problems of mathematical physics and mechanics. The LWFs arise via the method of separation of variables for the wave equation in ellipsoidal coordinates. The present paper introduces the Lamé's Quaternionic Wave Functions (LQWFs), which extend the LWFs to a non‐commutative framework. We show that the theory of the LQWFs is determined by the Moisil‐Theodorescu type operator with quaternionic variable coefficients. As a result, we explain the connections between the solutions of the Lamé's wave equation, on one hand, and the quaternionic hyperholomorphic and anti‐hyperholomorphic functions on the other. We establish analogues of the basic integral formulas of complex analysis such as Borel‐Pompeiu's, Cauchy's, and so on, for this version of quaternionic function theory. We further obtain analogues of the boundary value properties of the LQWFs such as Sokhotski‐Plemelj formulae, the ‐hyperholomorphic extension of a given Hölder function and on the square of the singular integral operator. We address all the text mentioned earlier and explore some basic facts of the arising quaternionic function theory. We conclude the paper showing that the spherical, prolate, and oblate spheroidal quaternionic wave functions can be generated as particular cases of the LQWFs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
99.
‘Soft energy’ provided within a thin film microfluidic platform, namely a vortex fluidic device (VFD), is effective in accelerating and promoting Diels–Alder reactions in the absence of any catalyst. Diels–Alder cycloadducts generated from different 9-substituted anthracenes and N-maleimides are formed in high yield in an aqueous medium using the confined mode of operation of the VFD. 相似文献
100.
CYP2C9酶与Warfarin结合模型的立体选择性理论研究 总被引:2,自引:0,他引:2
对CYP2C9酶与S-Warfarin复合物的晶体结构进行分子对接、分子动力学模拟、通道分析及结合自由能计算,发现原晶体结构中的结合模式为"亚稳态",提出了CYP2C9与S-Warfarin结合的可催化模式;比较了CYP2C9与S-和R-Warfarin结合的异同,确定了在结合过程中起重要作用的锚定氨基酸残基,尤其是位于活性位点区域的苯丙氨酸簇.在结合过程中这些残基通过芳香环的移动对稳定底物的结合模式起到至关重要的作用,阐明了该酶呈现相关底物选择性的原因.对于CYP2C9与底物对接模式及立体选择性的研究有助于在分子层面上理解特异性底物与酶的结合特点,为潜在的药物设计提供了合理可信的理论依据. 相似文献