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51.
A. Yu. Ershov D. G. Nasledov E. V. Parilova I. V. Lagoda V. V. Shamanin 《Russian Journal of Organic Chemistry》2014,50(8):1164-1174
Proceeding from natural amino acid L-asparagine and commercially available aldehydes a stereoselective synthesis was developed of (2S,4S)-2-alkyl(aryl)-3-(3-sulfanylpropanoyl)-6-oxohydropyrimidine-4-carboxylic acids, potential antihypertensive drugs, inhibitors of the angiotensin converting enzyme. 相似文献
52.
Belikov Mikhail Yu. Ievlev Mikhail Yu. Fedoseev Sergey V. Ershov Oleg V. 《Research on Chemical Intermediates》2020,46(7):3477-3490
Research on Chemical Intermediates - A series of negative T-type nitrile-rich photochromes containing a hydroxytricyanopyrrole acceptor was synthesized. It was shown that thermal stability of the... 相似文献
53.
Russian Journal of Organic Chemistry - The reaction of 4-halo-3-hydroxyfuro[3,4-c]pyridin-1(3H)-ones with acyclic and alicyclic secondary amines in ethyl acetate afforded the corresponding... 相似文献
54.
Lipin K. V. Ershov O. V. Fedoseev S. V. Mikhailov A. A. 《Russian Journal of Organic Chemistry》2020,56(1):177-180
Russian Journal of Organic Chemistry - Previously unknown 3-R-sulfanyl-5-amino-1-phenyl-1H-pyrazole-4-carbonitriles were synthesized by reactions of 2-[bis(alkylsulfanyl)methylidene]malononitriles... 相似文献
55.
B. G. Ershov A. F. Seliverstov N. L. Sukhov G. L. Bykov 《Russian Chemical Bulletin》1992,41(10):1805-1809
The sorption of Cu2+ ions by chitin and chitosan from aqueous solutions has been investigated, as well as the molecular structure of the complexes formed. The static exchange capacities have been determined, equal to 3.5 and 0.25 mmole/g for chitosan and chitin, respectively, and the partition coefficients (5000 and 70 g/ml). It has been shown that in complex formation a bond with the amino group is formed as the result of the substitution of a proton in the latter. The EPR spectra of these complexes have been obtained and their radiospectroscopic parameters determined (g
= 2.334,g
= 2.054,A = 0.0156 cm–1, andB = 0.0028 cm–1 for chitin, andg
= 2.231,g
= 2.048,A = 0.0192 cm–1, andB = 0.0025 cm–1 for chitosan). For chitosan the ligands are two nitrogen atoms of the amino groups and two oxygen atoms of the hydroxyl groups in the position C3 of adjacent glucosamine rings; for chitin, the oxygen atoms of the acetyl groups take part in addition in the complex formation. The analysis of the radiospectroscopic parameters and their comparison with published data lead to the conclusion that the Cu2+ complex with chitosan has a tetragonal symmetry, while the complex with chitin most probably has an octahedral structure.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2305–2311, October, 1992. 相似文献
56.
Silver nanoparticles are prepared by reducing Ag+ ions with sodium borohydride in aqueous solutions containing carbonate ions (5 × 10−5−1 × 10−2 mol l−1). It is established that carbonate ions represent an efficient stabilizer that provides nanoparticles with electrostatic
protection via the formation of an electrical double layer. The maximum stability of a silver dispersion is observed at a
carbonate ion concentration of 1 × 10−3 mol l−1. The average size of silver nanoparticles is 10.0 ± 2.5 nm. The formation kinetics of silver nanoparticles is described by
an equation for a first-order reaction with a rate constant of 2.3 × 10−3 s−1 (±20%). 相似文献
57.
Reactions induced by collisions of beams of unstable nuclei with nuclear targets are studied. Kinematically full breakup reactions
are considered. A microscopic four-body model of the breakup of two-neutron-halo nuclei is formulated with allowance for special
features of their structure. The model relies on the distorted-wave method and creates a basis for the spectroscopy of the
continuous spectrum via a consistent analysis of various correlation cross sections. 相似文献
58.
M. A. Ershov E. V. Grigor’eva A. I. Guseva N. Ya. Vinogradova D. A. Potanin V. S. Dorokhov P. A. Nikul’shin K. A. Ovchinnikov 《Russian Journal of Applied Chemistry》2017,90(9):1402-1411
Prospects for using furfural derivatives as octane boosters for gasoline are discussed on the basis of analysis of their physicochemical and operation properties. Knock resistance data, toxicity parameters, and results of motor bench tests are considered for furan compounds, furfural ethers, furfurylamine, and other furfural derivatives. 相似文献
59.
60.