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231.
1,3-Bis(4-bromobutyl)-6-methyluracil reacts with diethyl 2-(dimethylamino)ethylphosphonate to form a bisquaternary ammonium
salt, whereas the reaction of 1,3-bis-(6-bromohexyl)-6-methyluracil with diethyl 2-(diethylamino)ethyl phosphate gives 1,3-bis-[(6-diethoxyphosphoryloxy)hexyl]-6-methyluracil
and 1,1,4,4-tetraethylpiperazinium dibromide.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1130–1132, June, 2000. 相似文献
232.
Mikhael Pudovik Alexander Burilov Irina Nikolaeva Dmitry Haritonov Natalia Bashmakova Vladimir Reznik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The phosphorylation of dialkylaminomethylated calix[4]resorcinarenes with P(m)-amides and P(TV)chlorides under various conditions results in the formation of different structures with phosphorus containing fragments fixed on the cavity rim. Hydrophosphoryl compounds based on dialkylaminomethylated calix[4]resorcinarenes have been synthesized and some of their properties investigated. 相似文献
233.
Fattakhov S. G. Shulaeva M. M. Reznik V. S. 《Russian Journal of General Chemistry》2001,71(7):1091-1095
1-Methyl or 1-benzyl 3,5-bis(-bromoalkyl) isocyanurates with the alkyl chain comprising 3 through 6 methylene units were synthesized by the reaction of disodium methyl and benzyl isocyanurates with ,-dibromoalkanes. The reaction of disodium methyl and benzyl isocyanurates with ethylene chlorohydrin was used to obtain 1-methyl or 1-benzyl 3,5-bis(2-hydroxyethyl) isocyanurates whose treatment with PBr3 or SOCl2 gave the corresponding 1-alkyl 3,5-bis(2-haloethyl) isocyanurates. 1-Methyl and 1-benzyl 3,5-bis-(chloromethyl) isocyanurates were prepared by treatment with SOCl2 of 1-methyl or 1-benzyl 3,5-bis(hydroxymethyl) isocyanurates obtained, in their turn, by condensation of methyl and benzyl isocyanurates with formaldehyde. 相似文献
234.
Roey Tzezana Stanislav Reznik Jacob Blumenthal Eyal Zussman Shulamit Levenberg 《Macromolecular bioscience》2012,12(5):598-607
Morphogen gradients have been associated with differential gene expression and are implicated in the triggering and regulation of developmental biological processes. This study focused on creating morphogenic gradients through the thickness of hydrospun scaffolds. Specifically, electrospun poly(ε‐caprolactone) fibers were loaded with all‐trans‐retinoic acid (ATRA), and designed to release ATRA at a predetermined rate. Multilayered scaffolds designed to present varied initial ATRA concentrations were then exposed to flow conditions in a bioreactor. Gradient formation was verified by a simple convection‐diffusion mathematical model approving establishment of a continuous solute gradient across the scaffold. The biological value of the designed gradients in scaffolds was evaluated by monitoring the fate of murine embryonal carcinoma cells embedded within the scaffolds. Cell differentiation within the different layers matched the predictions set forth by the theoretical model, in accordance with the ATRA gradient formed across the scaffold. This tool bears powerful potential in establishing in vitro simulation models for better understanding the inner workings of the embryo.
235.
E. P. Zhil'tsova L. A. Kudryavtseva G. A. Gainanova A. P. Timosheva A. S. Mikhailov R. H. Giniyatullin A. A. Nafikova V. S. Reznik A. I. Konovalov 《Russian Journal of General Chemistry》2005,75(11):1729-1734
Reactions of a macrocycle containing three pyrimidine fragments and N,N′-bis(2-methylthio-6-methylpyrimidin-4-yl)-hexamethylenediamine with p-nitrophenyl bis(chloromethyl)phosphinate in the micellar solutions of cetyltrimethylammonium bromide, polyethyleneglycol-600 laurate and their mixture in chloroform was investigated spectrophotometrically. Catalytic activity of micelles depends on their structure, concentration of surfactants, molar fraction of the latter in solution, and structure of the nucleophilic reagent. 相似文献
236.
M. A. Voronin F. G. Valeeva L. Ya. Zakharova R. Kh. Giniyatullin V. E. Semenov V. S. Reznik 《Colloid Journal》2010,72(3):323-331
Abstract Tensiometry, conductometry, dynamic light scattering, and potentiometry are used to study the aggregation of a new
amphiphilic alkylated pyrimidinophane (APP) in aqueous solutions in the presence of polyethylen-imine. The new geminal surfactant is shown to possess high micellization
ability (CMC = 0.00001 M) due to the presence of an additional alkyl radical in the pyrimidine fragment. APP aggregates are characterized by a low degree of counterion binding (lower than 50%). Spectrophotometry is employed to investigate
the catalytic activities of individual surfactant solutions and solutions of APP—polyethylenimine binary mixtures with respect to the hydrolysis of phosphonic acid esters. The effect of APP on phosphonate hydrolysis is typical of cationic surfactants. The higher acceleration is observed for the hydrolysis of a
more hydrophobic phophonate. 相似文献
237.
O.R. Kozyrev S.N. Reznik Yu.A. Stepanyants 《Journal of Applied Mathematics and Mechanics》2009,73(2):188-195
The free motion of a thin cylindrical body is investigated based on a previously derived expression for the radiation force acting on moving point sources in a stratified fluid. The fundamental equations of motion are derived, the limits of applicability of the approximation used are indicated and the results of calculations of typical trajectories of a body which begins to move with a specified velocity from a position of neutral buoyancy at an angle to the horizon are presented. Calculations of the trajectory of motion of a thin cylindrical body in a stratified fluid when the total radiation force is taken into account show that the effect of the lateral component of this force is considerable and leads not only to quantitative corrections but also to qualitative effects (for example, to an increase in the oscillations of the body and a change in its direction of motion). The results obtained pertain both to the motion of solids in fluids and to the translational motion of vortex dipoles in weakly stratified media. 相似文献
238.
We propose a method for simulating (2+1)D compact lattice quantum-electrodynamics, using ultracold atoms in optical lattices. In our model local Bose-Einstein condensates' (BECs) phases correspond to the electromagnetic vector potential, and the local number operators represent the conjugate electric field. The well-known gauge-invariant Kogut-Susskind Hamiltonian is obtained as an effective low-energy theory. The field is then coupled to external static charges. We show that in the strong coupling limit this gives rise to "electric flux tubes" and to confinement. This can be observed by measuring the local density deviations of the BECs, and is expected to hold even, to some extent, outside the perturbative calculable regime. 相似文献
239.
240.
Vaycheslav E Semenov Valentin D Akamsin Vladimir S Reznik Alla V Chernova Galina M Dorozhkina Yurij Ya Efremov Adilay A Nafikova 《Tetrahedron letters》2002,43(52):9683-9686
Acyclic and cyclic counterparts containing thymine and two 3,6-dimethyluracil fragments bridged by methylene chains have been prepared and studied by UV and NMR spectroscopy; in water the uracil units of the acyclic counterpart form an intramolecular stack but arrange in a linear array in chloroform while the fragments of the uracilophane form an intramolecular stack both in chloroform and water; uracil units of bis(3,6-dimethyluracil-1-yl)butane and the macrocyclic counterpart form a stack in chloroform. 相似文献