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排序方式: 共有347条查询结果,搜索用时 15 毫秒
91.
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93.
Antipin I. S. Stoikov I. I. Khrustalev A. A. Konovalov A. I. 《Russian Chemical Bulletin》2001,50(11):2134-2143
A new type of macrocyclic receptor able to bind organic substrates containing carboxy and carboxylate groups was designed on the basis of 1,3-disubstituted calix[4]arenes. A series of disubstitited calix[4]arenes were prepared in 60—80% yields by selective 1,3-alkylation of p-tert-butylcalix[4]arene. The compounds obtained were tested as carriers for dl-tartaric, glycolic, dl-amygdalic, and dl-glutamic acids through liquid membranes immobilized on a polymer matrix. The structural factors favorable for the transport of these hydrophilic substrates through lipophilic membranes were established. 相似文献
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95.
Chyong Khong Khieu A. T. Soldatenkov An’ Le Tuan A. N. Levov A. F. Smol’yakov V. N. Khrustalev M. Yu. Antipin 《Russian Journal of Organic Chemistry》2011,47(5):766-770
By triple condensation of thiourea or guanidine with 1,ω-bis(2-formylphenoxy)-3-oxapentane and ammonium acetate first representatives
of the new class of ethers bis(benzo)aza-14-crown-4 were obtained in 28–73% yield that included as a subunit a symm-perhydrotriazine ring. This reaction also proceeds readily with N-monomethyl- and N-monopropenyl-substituted thioureas affording
the corresponding derivatives of triazinoazacrown ether. At the same time urea in the similar condensation does not form the
expected perhydrotriazinoazacrown ether. The molecular structure of one perhydroazacrown ether as a complex with a chloroform
molecule was established by XRD analysis. 相似文献
96.
O. I. Gromov E. N. Golubeva V. N. Khrustalev T. Kálai K. Hideg A. I. Kokorin 《Applied magnetic resonance》2014,45(10):981-992
Two short nitroxide biradicals of similar composition, R6′–R6′ (B0) and R6′–(C ≡ C)–R6′ (B1), where R6′ is 1-oxyl-2,2,6,6-tetramethyl-3,4-ene-nitroxide ring, have been investigated by electron paramagnetic resonance spectroscopy and X-ray structural analysis. Quantum chemical calculations at UDFT/B3LYP/cc-pVDZ level were also performed and compared with the X-ray structural data. Zero-field splitting parameters D for B0 and B1 were found to be equal ?0.0048 and ?0.0022 cm?1, respectively, in good agreement with quantum chemical prediction. Potential energy surface scans corresponding to pathways of the conformational rearrangements were calculated; rotation barriers for B0 and B1 were found to be 19.2 and 4.0 kJ/mol, respectively; and structural rigidity and probable differences in biradicals behavior are discussed. Calculations of spin density distribution in biradicals B0 and B1 were also carried out. 相似文献
97.
Yu. G. Gololobov I. R. Golding S. V. Barabanov V. N. Khrustalev I. A. Garbuzova A. S. Peregudov 《Russian Journal of General Chemistry》2013,83(5):959-968
New N-methylmorpholinium and triethylammonium salts of 2,4-dinitrophenylcyanoacetic acid were obtained. Their electronic and spatial structure was studied by IR, NMR spectroscopy (including two-dimensional correlation spectra HMQC and HMBC), as well as by XRD analysis. 相似文献
98.
Linko R. V. Ryabov M. A. Polyanskaya N. A. Dorovatovskii P. V. Khrustalev V. N. 《Crystallography Reports》2019,64(6):887-893
Crystallography Reports - 1,3-Dicarbonyl compounds were synthesized by the reaction of 9,10-phenanthrenequinone with acetylacetone and acetoacetic ester followed by the reduction and were... 相似文献
99.
B.P. Khrustalev A.D. Balaev V.G. Pozdnyakov L.I. Vershinina 《Solid State Communications》1985,55(8):657-662
The results of electron-microscopic investigation of the structure and spin-wave resonance of thin ferromagnetic Fe100-x(SiO)x films are presented in the paper. The correlation radii of fluctuations of the exchange interaction parameter are determined from the analysis of the experimental results of spin-wave resonance. These radii are compared with characteristic sizes of the structural clusters in the films. 相似文献
100.