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51.
We obtain some general results on Sasakian Lie algebras and prove as a consequence that a (2n + 1)-dimensional nilpotent Lie group admitting left-invariant Sasakian structures is isomorphic to the real Heisenberg group H 2n + 1. Furthermore, we classify Sasakian Lie algebras of dimension five and determine which of them carries a Sasakian α-Einstein structure. We show that a five-dimensional solvable Lie group with a left-invariant Sasakian structure and which admits a compact quotient by a discrete subgroup is isomorphic to either H 5 or a semidirect product ? ? (H 3 × ?). In particular, the compact quotient is an S 1-bundle over a four-dimensional Kähler solvmanifold. 相似文献
52.
Feenstra RW van den Hoogenband A Stroomer CN van Stuivenberg HH Tulp MT Long SK van der Heyden JA Kruse CG 《Chemical & pharmaceutical bulletin》2006,54(9):1326-1330
The syntheses of several 1-aryl-4-(arylpyridylmethyl)piperazines (4) and their affinities for dopamine D(2) and serotonin 5-HT(1A) receptors are described. The compounds were evaluated both in vitro and in vivo, resulting in the identification of the drug candidate SLV313 (4e) with equipotent and full D(2) receptor antagonism and 5-HT(1A) receptor agonism. Minor structural modifications in SLV313 revealed the possibility of designing compounds possessing varying degrees of partial agonism on one or both target receptors. 相似文献
53.
Okram B Nagle A Adrián FJ Lee C Ren P Wang X Sim T Xie Y Wang X Xia G Spraggon G Warmuth M Liu Y Gray NS 《Chemistry & biology》2006,13(7):779-786
Kinase inhibitors that bind to the ATP cleft can be broadly classified into two groups: those that bind exclusively to the ATP site with the kinase assuming a conformation otherwise conducive to phosphotransfer (type I), and those that exploit a hydrophobic site immediately adjacent to the ATP pocket made accessible by a conformational rearrangement of the activation loop (type II). To date, all type II inhibitors were discovered by using structure-activity-guided optimization strategies. Here, we describe a general pharmacophore model of type II inhibition that enables a rational "hybrid-design" approach whereby a 3-trifluoromethylbenzamide functionality is appended to four distinct type I scaffolds in order to convert them into their corresponding type II counterparts. We demonstrate that the designed compounds function as type II inhibitors by using biochemical and cellular kinase assays and by cocrystallography with Abl. 相似文献
54.
A numerical approach for the topological optimization of 3D linear elastic problems using boundary elements and the topological derivative is presented in this work. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
55.
Gil A Karhánek D Miró P Antonio MR Nyman M Bo C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(27):8340-8346
Anionic uranyl-peroxide U(28) nanocapsules trap cations and other anions inside, whose structures cannot be resolved by X-ray diffraction, owing to crystallographic disorder. DFT calculations enabled the complete characterization of the geometry of these complex systems and also explained the origin of the disorder. The stability of the capsules was strongly influenced by the entrapped cations. Excellent agreement between experiment and theory was also obtained for the electronic character and redox properties. 相似文献
56.
Gómez-Suárez A Ramón RS Slawin AM Nolan SP 《Dalton transactions (Cambridge, England : 2003)》2012,41(18):5461-5463
New procedures for the synthesis of [Au(NHC)(OH)] are reported. Initially, a two-step reaction via the digold complex [{Au(NHC)}(2)(μ-OH)][BF(4)] was probed, enabling the preparation of the novel [Au(SIPr)(OH)] complex and of its previously reported congener [Au(IPr)(OH)]. After further optimization, a one-step procedure was developed. 相似文献
57.
The dynamics of water confined to mesoporous regions in minerals such as swelling clays and zeolites is fundamental to a wide range of resource management issues impacting many processes on a global scale, including radioactive waste containment, desalination, and enhanced oil recovery. Large-scale atomic models of freely diffusing multilayer smectite particles at low hydration confined in a silicalite cage are used to investigate water dynamics in the composite environment with the ReaxFF reactive force field over a temperature range of 300-647 K. The reactive capability of the force field enabled a range of relevant surface chemistry to emerge, including acid/base equilibria in the interlayer calcium hydrates and silanol formation on the edges of the clay and inner surface of the zeolite housing. After annealing, the resulting clay models exhibit both mono- and bilayer hydration structures. Clay surface hydration redistributed markedly and yielded to silicalite water loading. We find that the absolute rates and temperature dependence of water dynamics compare well to neutron scattering data and pulse field gradient measures from relevant samples of Ca-montmorillonite and silicalite, respectively. Within an atomistic, reactive context, our results distinguish water dynamics in the interlayer Ca(OH)(2)·nH(2)O environment from water flowing over the clay surface, and from water diffusing within silicalite. We find that the diffusion of water when complexed to Ca hydrates is considerably slower than freely diffusing water over the clay surface, and the reduced mobility is well described by a difference in the Arrhenius pre-exponential factor rather than a change in activation energy. 相似文献
58.
Paola Morando Concepción Muriel Adrián Ruiz 《Journal of Nonlinear Mathematical Physics》2019,26(2):188-201
The notion of solvable structure is generalized in order to exploit the presence of an algebra of symmetries for a kth-order ordinary differential equation with k > 3. In this setting, the knowledge of a generalized solvable structure for allows us to reduce to a family of second-order linear ordinary differential equations depending on k ? 3 parameters. Examples of explicit integration of fourth and fifth order equations are provided in order to illustrate the procedure. 相似文献
59.
Turra Christian Fernandes Elisabete A. De Nadai Bacchi Márcio Arruda Sarriés Gabriel Adrián Reyes Andrés Enrique Lai 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):219-224
Journal of Radioanalytical and Nuclear Chemistry - The objective of this study was to evaluate temporal variability of rare earth elements (REE) in soils of citrus agroecosystems. Instrumental... 相似文献
60.
Perissinotti LL Turjanski AG Estrin DA Doctorovich F 《Journal of the American Chemical Society》2005,127(2):486-487
We report an investigation of the reaction between (S)-nitroso-l-cysteine ethyl ester and l-cysteine ethyl ester as a model of physiologically relevant transnitrosation processes. Our theoretical and experimental evidence clearly supports the existence of a nitroxyl disulfide intermediate in solution. 相似文献