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1.
The influence of sunflowerseed and cottonseed oils and also of fractions of normal and oxidized triacylglycerols isolated from them on cytochrome P-450 from rat liver microsomes has been investigated.  相似文献   
2.
Translated from Sistemnoe Programmirovanie i Modeli Issledovaniya Operatsii, pp. 183–194, 1993.  相似文献   
3.
The properties of 1,3-dimethyl-6,7-dialkoxy-2-benzopyrylium salts were studied. The heterocyclic oxygen atom is readily replaced by nitrogen by reaction of the 2-benzopyrylium salts with primary amines, hydrazine, phenylhydrazine, glycine ethyl ester, and hydroxylamine; reaction with secondary amines leads to naphthalene derivatives. The activities of the methyl groups in the 1 and 3 positions of the heterocyclic ring are compared.For Communication IX, see [6].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1308–1312, October, 1970.  相似文献   
4.
The addition of 1-aryl-2-bromodiazene 1-oxides to olefins yields 1-aryl-2-(2-bromoalkyl)diazene 1-oxides (4). A radical mechanism of the reaction has been suggested. Compounds4 decompose to give bromohydrazones of formaldehyde and aldehydes. The structural factors that affect the rate of this process are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 917–923, May, 1995.The work was carried out in the Scientific Educational Center of the Institute of Organic Chemistry of the RAS with financial support of the Russian Foundation for Basic Research (Project No. 93-03-18461).  相似文献   
5.
The polarographic reduction of adenine and its 9-(,)-dihydroxy-2-alkyl) derivatives on a short-period mercury electrode in strongly acidic media is determined by the rate of diffusion of the corresponding cations and, at pH values that exceed the pKa values, by the kinetics of surface protonation of the uncharged molecules; this was proved by the dependence of the limiting current on the height of the mercury column, the temperature, and the depolarizer concentration. The polarographic reduction of adenine, adenosine, 9-(,-di-hydroxy-2-alkyl)adenines, and the corresponding phosphates in acidic media proceeds with the loss of sic electrons per molecule. The similar trends of the change in the half-wave potentials and the numerical pKa values is associated with the fact that the site of protonation is simultaneously the site of nucleophilic attack by the electron during electrical reduction.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1675–1678, December, 1977.  相似文献   
6.
The mixture of 9-, 3-, and 7-benzyl-6-substituted purines is formed in almost quantitative yield by the alkylation of 6-benzylamino-, 6-furfurylamino-, 6-methylthio-, and 6-chloropurine with benzyl halides in the biphasic system of the liquid-liquid or liquid-solid type in the presence of interphase catalysts (quaternary ammonium salts, 18-crown-6). The catalytic activity of the quaternary ammonium salts increases with the increase in the lipophilicity of the cation. Taking the alkylation of 6-benzylaminopurine as an example, the possibility of the application of triphasic catalysis in the alkylation reaction of purines is indicated. The alkylation of 6-substituted purines with isopropyl bromide proceeds regioselectively under the conditions of the interphase catalysis with the formation of the corresponding 9-isopropylpurines.For the preliminary communication, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 113–118, January, 1987.  相似文献   
7.
A trans configuration with an axial orientation of both the purine ring and the furyl ring or the ethoxy group in the 2 position of the dioxane residue was established by PMR spectroscopy for 9-(2-furyl-1,3-dioxan-5-yl)- and 9-(2-ethoxy-2-methyl-1,3-dioxan-5-yl)purine. A comparative analysis of the mass spectra of these compounds makes it possible to confirm conclusions regarding their stereochemistry drawn on the basis of the PMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–696, May, 1984.  相似文献   
8.
Temperature dependence of the reaction rate of H2 oxidation on nickel oxide and solid solutions of nickel ions in MgO prepared at 573–1373 K, has been studied. The variation of the catalytic properties with temperature is attributed to the presence of nickel ions in different oxidation states simultaneously, i. e. Ni(II) and Ni(III).
H2 MgO, 573–1373 K. — Ni(II) Ni(III).
  相似文献   
9.
10.
It was found that lithium tetraalkoxyborates are highly efficient gelling agents for hydrocarbons. The viscosity of liquid hydrocarbons can be increased to a desired degree by mixing them with a gelling composition of lithium tert-butoxide Li-O-C(CH3)3 and trialkoxyborate B(OC8H17)3 in equimolecular amounts. Oil gelled by this composition has a rubberlike consistency, which retains its shape; therefore, oil spills treated with the use of this method can be more efficiently recovered mechanically or by hand.  相似文献   
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