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71.
By acylation of substituted 2-aminoarylpyrimidines with 5-phenyl(p-tolyl)isoxazole- and 4,5-dichloroisothiazole-3-carbonyl chlorides new amides of pyrimidine series were obtained.  相似文献   
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We find that neutron transmission of magnetic systems with the noncollinear magnetization contains a time-odd correlation. The neutron reflection from such a system violates detailed balance. Time-odd correlation is shown to violate T-invariance even in the presence of an irreversibly produced by losses and described by the imaginary part in the neutron-matter interaction.  相似文献   
74.
New amides of 2-(arylamino)pyrimidine series were synthesized with pharmacophoric fragments of tyrosine kinase and histone deacetylase inhibitors and functional groups providing chemosorption of compounds on nanocarriers.  相似文献   
75.
The $ \mathcal{N} $ \mathcal{N} -extended Supersymmetric Quantum Mechanics is deformed via an abelian twist which preserves the super-Hopf algebra structure of its Universal Enveloping Superalgebra. Two constructions are possible. For even $ \mathcal{N} $ \mathcal{N} one can identify the 1D $ \mathcal{N} $ \mathcal{N} -extended superalgebra with the fermionic Heisenberg algebra. Alternatively, supersymmetry generators can be realized as operators belonging to the Universal Enveloping Superalgebra of one bosonic and several fermionic oscillators. The deformed system is described in terms of twisted operators satisfying twist-deformed (anti)commutators. The main differences between an abelian twist defined in terms of fermionic operators and an abelian twist defined in terms of bosonic operators are discussed.  相似文献   
76.
A simple and highly efficient procedure has been proposed for the synthesis of heterocyclic and aromatic N-benzyl amines via reductive amination of substituted aromatic aldehydes in the presence of sodium tetrahydridoborate-acetic acid system generating reactive sodium triacetoxyhydridoborate.  相似文献   
77.
A series of 2,2‐dimethyl‐5‐(5′‐R‐hetarylidene)‐1,3‐dioxane‐4,6‐diones has been synthesized for examing a structure–activity relationship. Furyl and thienyl derivatives of Meldrum's acid possess neurotropic activity comprising both depriming and activating components. Comparison of acute toxicity of carbon, silicon and germanium analogues in the furan series of the compounds has demonstrated that the germanium derivative is 11.5 times less toxic than the carbon analogue and four times less toxic than the silicon derivative. 2,2‐Dimethyl‐5‐(5′‐triethylsilyl‐2′‐thenylidene)‐1,3‐dioxane‐4,6‐dione has moderate toxicity with the highest neurotropic and cytotoxic activity Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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A neutron albedo from arbitrary homogeneous and finely grained substances is examined on the basis of a new, algebraic, method. In the approximation of an isotropic distribution of incident and reflected neutrons, it is shown that, in the case of thermal neutrons, coherent scattering on individual particles of finely grained media increases only slightly the transport cross section, but, at a given wall thickness, it reduces the albedo because of a decrease in the density of the substance. A significant increase in the albedo is possible only for neutrons of wavelength on the order of dimensions of a powder grain. The angular distribution of reflected neutrons is discussed, and it is proven that a deviation of this distribution from an isotropic one does not lead to a change in the magnitude of the albedo.  相似文献   
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