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1.
Zh. A. Krasnaya T. S. Stytsenko V. I. Avdeeva D. Ya. Shagalova 《Russian Chemical Bulletin》1989,38(1):80-86
| 1. | A series of tetracyanopolymethines has been synthesized by condensation of aminals and aminal-acetals of conjugated -dimethylaminoaldehydes with malonodinitrile. |
| 2. | These tetracyanopolymethines can be used as the anionic components in cation-anion cyanine dyes. |
| 3. | The electronic absorption spectra of these newly synthesized dyes were studied in both polar and nonpolar solvents. Specific cation-anion interaction and complex formation has been shown to occur in several of these cation-anion dyes in nonpolar solvents. |
2.
| 1. | A series of C-functional derivatives of (3)-1,2-dicarbaundecaborate was synthesized and some of their properties were studied. |
| 2. | Apparent ionization constants of acids of the (3)-1,2-dicarbaundecaborate series were measured and it was found that they are very weak carboxylic acids. |
| 3. | Upon reaction with excess LiA1H4, under mild conditions the carbonyl, *20c \CH(OH) / \begin{array}{*{20}c} \backslash \\ {CH(OH)} \\ / \\ \end{array} , and CH2OH groups of dicarbaundecaborate ketones and alcohols are reduced to CH2 and CH3 groups, respectively. |
| 4. | The effect of Grignard reagent on ketones and esters of the dicarbaundecarbprate series was studied and it was established that the composition of reaction products depends both on the steric hindrance of the carbonyl group and on the electron-donating effect of the (3)-1,2-dicarbaundecaborate substituent. |
3.
S. G. Vul'fson A. B. Teitel'baum T. G. Mannafov A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(1):86-89
| 1. | Molecules of arylvinyl selenides have a maximally conjugated planar s-trans structure, |
| 2. | The conformations of arylvinyl sulfides are determined by the ratio of the energies of conjugation and steric repulsion of atoms; the disturbance of coplanarity occurs on account of rotation of the aryl radicals. |
4.
The energy metabolism of a mammalian cell line grown in vitro was analyzed by substrate consumption rates and metabolic flux
measurements. The data allowed the determination of the relative importance of the pathways of glucose and glutamine metabolism
to the energy requirements of the cell. Changes in the substrate concentrations during culture contributed to the changing
catalytic activities of key enzymes, which were determined.
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| 1. | A murine B-lymphocyte hybridoma (PQXB1/2) was grown in batch culture to a maximum cell density of 1–2×106 cells/mL in 3–4 d. The intracellular protein content showed a maximum value during the exponential growth phase of 0.55 mg/106 cells. Glutamine was completely depleted, but glucose only partially depleted to 50% of its original concentration when the cells reached a stationary phase following exponential growth. |
| 2. | The specific rates of glutamine and glucose utilization varied during culture and showed maximal values at the midexponential phase of 2.4-nmol/min/106 cells and 4.3 nmol/min/106 cells, respectively. |
| 3. | A high proportion of glucose (96%) was metabolized by glycolysis, but only limited amounts by the pentose phosphate pathway (3.3%) and TCA cycle (0.21%). |
| 4. | The maximum catalytic activity of hexolinase approximates to the measured flux of glycolysis and is suggested as a rate-limiting step. In the stationary phase, the hexokinase activity reduced to 11% of its original value and may explain the reduced glucose utilization at this stage. |
| 5. | The maximal activities of two TCA cycle enzymes were well above the measured metabolic flux and are unlikely to pose regulatory barriers. However, the activity of pyruvate dehydrogenase was undetectable by spectrophotometric assay and explains the low level of flux of glycolytic metabolites into the TCA cycle. |
| 6. | A significant proportion of the glutamine (36%) utilized by the cells was completely oxidized to CO2. |
| 7. | The measured rate of glutamine transport into the cells approximated to the metabolic flux and is suggested as a rate-limiting step. |
| 8. | Glutamine metabolism is likely to occur via glutaminase and amino transaminase, which have significantly higher activities than glutamate dehydrogenase. |
| 9. | The calculated potential ATP production suggests that, overall, glutamine is the major contributor of cellular energy. However, at the midexponential phase, the energy contribution from the catabolism of the two substrates was finely balanced—glutamine (55%) and glucose (45%). |
5.
S. F. Vasilevskii A. N. Sinyakov M. S. Shvartsberg I. L. Kotlyarevskii 《Russian Chemical Bulletin》1976,25(10):2134-2138
| 1. | Depending on the conditions, the reaction of methyl aryl ketones with phosphorus pentachloride leads to products from substitution of the carbonyl oxygen by chlorine, αβ-dichlorovinylarenes, or compounds with higher degrees of chlorination. |
| 2. | By eliminating a molecule of hydrogen chloride under the influence of an equimolar amount of sodium amide in ammonia, substituted, α,β-dichloroethylenes give high yields of the respective 2-chloroacetylene. |
| 3. | The synthesis of a series of ethynyl- and β-chloroethynylpyrazoles from methylpyrazolyl ketones was realized. |
6.
| 1. | The rate constant for the destruction of radical pairs decreases with increase in the distance between the traps of the H atom. |
| 2. | A mechanism was proposed for the destruction of radical pairs, according to which the main channel for hydrogen transfer during annealing does not coincide with the channel for phototransfer when the RP are formed. |
| 3. | Based on a formally kinetic analysis for a stepwise rate, distribution parameters based on the activation energies were found for the deuterated and undeuterated samples. A superficial estimate was made of the change in the activation energy when the distance between the unpaired electrons in the radical pairs is changed by one unit of length. |
7.
| 1. | Thermodesorption measurements have shown the surface of aluminum-nickel-tungsten sulfide catalysts to be nonuniform with respect to cyclohexane, the nonuniformity being characterized by an exponential distribution, a step adsorption isotherm, and a logarithmic fall off of the desorption activation energy with increasing surface coverage. |
| 2. | The degree of cyclohexane coverage of the catalyst surface is increased by the presence of hydrogen, and the energy of adsorptional bonding is reduced. |
| 3. | Cyclohexane bonds to the catalyst surface more weakly than does benzene, and can be completely displaced from the surface by the latter. |
8.
B. A. Glazun R. N. Kurnosova M. M. Dubinin I. V. Zhilenkov S. S. Levchenko 《Russian Chemical Bulletin》1976,25(1):8-11
| 1. | In NaA zeolite a homocharge is formed by charges deposited on the surface of the zeolite from the gas gap between the electrode and the specimen. |
| 2. | The existence of thermoelectret effects has been found in the systems NaA-zeolite -air, NaA-helium, NaA-nitrogen, and NaA-oxygen. |
| 3. | The thermoelectret effects are caused by both the accumulation of charges in the specimen and the adsorption of molecules in the electric field. |
| 4. | A low mobility has been noted for adsorbed molecules in the electret state of the system. |
9.
| 1. | The condensation of 1,2-hydroxylamino oximes with biacetyl leads to 1-hydroxy-2-acetyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides. |
| 2. | When 1-hydroxy-2-acetyl-2,5,5-trimethyl-4-phenyl-3-imidazoline 3-oxide is oxidized the CH3CO group is cleaved to give the 5H-imidazole 1,3-dioxide. |
| 3. | Stable nitroxyl radicals were obtained when the 1-hydroxy-2-oximiaoethyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides are oxidized. |
10.
| 1. | Following the CNDO/2 approximation to the SCF MO LCAO method, electronic parameters have been calculated for the molecules and ions of various nitro compounds. |
| 2. | Calculated values of the dipole moment and enthalpy of atomization proved to be in satisfactory agreement with the experimentally determined values, the maximum deviation between them amounting to 1.4% for the aromatic systems. |
| 3. | The nitro compound parameters most sensitive to change in the intramolecular interaction are the C-N bond energy and the charges on the carbon and halide atoms. |
11.
K. L. Rogozhin A. N. Rodionov S. G. Smirnov D. N. Shigorin O. P. Syutkina V. I. Lodochnikova K. A. Kocheshkov 《Russian Chemical Bulletin》1976,25(2):319-322
| 1. | There is a regular increase in the energy of the lowest singlet and triplet excited levels in the aromatic derivatives of the elements C, Si, Ge, Sn and N, P, As, Sb, Bi, which is consistent with the quantum-mechanical model of the mixing of the electronic states of the aromatic system with states involving p and s orbitals of the heteroatom with different energies and symmetries. |
| 2. | The yields of the radiative electronic transitions regularly decrease, and the probabilities of nonradiative intramolecular electronic transitions increase. |
| 3. | The temperature effects inthe 300–77°K range in the electronic absorption spectra have been found and are associated with a postulated change in the spatial configuration of the compounds investigated. |
12.
B. A. Arbuzov O. Éxsner A. P. Timosheva V. E. Kataev S. G. Vul'fson A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(6):1206-1212
| 1. | The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical. |
| 2. | In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane. |
| 3. | The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers. |
13.
R. G. Kostyanovskii V. P. Leshchinskaya R. K. Alekperov G. K. Kadorkina L. L. Shustova Yu. I. Él'natanov G. L. Gromova A. É. Aliev I. I. Chervin 《Russian Chemical Bulletin》1988,37(11):2315-2323
| 1. | An efficient method of aziridine dimer synthesis is presented involving reaction of aziridine with esters of strong organic acids followed by alkaline hydrolysis of the resultant N-acyl derivatives. |
| 2. | New N-acyl and carbamoyl derivatives of aziridine dimer and trimer were synthesized. |
| 3. | Linear and branched isomers of aziridine tetramer and also diastereomers of 2-methylaziridine dimer were isolated and characterized. |
| 4. | An efficient regiospecific synthesis of 2,2-dimethylaziridine dimer and trimer was developed. |
14.
| 1. | The authors have studied the formation of electron and hole paramagnetic centers in gamma-irradiated magnesium hydroxide and oxide with various degrees of dehydration. |
| 2. | Rise in the temperature of preliminary heat treatment of the magnesium oxide causes an increase in the radiation-chemical yield of FS + centers and a decrease in that of V su – centers. |
| 3. | The thermal stability of paramagnetic centers in magnesium oxide increases as the hydroxyl group content decreases. |
15.
L. A. Rozov Yu. V. Zeifman N. P. Gambaryan Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(12):2560-2566
| 1. | Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes. |
| 2. | It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied. |
| 3. | The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal. |
16.
| 1. | Study has been made of the fragmentation paths in chemical ionization of β-methyl-2,3,4,6-tetra-O-methyl-D-galactopyranoside. |
| 2. | The quasimolecular ions of this compound are capable of successive splitting of one, two, and three methanol molecules, the preferred positions for methoxyl elimination being 1, 3, and 4, respectively. |
17.
| 1. | The molecular-sieve properties of a number of synthetic and natural chabazites have been investigated. |
| 2. | Characteristic differences have been revealed in the molecular-sieve properties, thermal stability, and x-ray characteristics between the two groups of the zeolites studied. |
| 3. | A reversal of the molecular-sieve effect on passing from the calcium to the sodium-calcium forms of certain synthetic and natural chabazites has been observed. |
18.
| 1. | Replacing Na+ ions by Ca2+in zeolites leads to a significant shift of the region in which thermally stimulated polarographic [TSD] current peaks appear toward higher temperatures. |
| 2. | Reducing the cation content in zeolites leads to a decrease in the intensity of TSD currents. |
| 3. | The data obtained-can be explained by the differences in the distributions of the cations between different crystallographic positions in the zeolite lattices. |
19.
| 1. | N-Ethyl and N-isopropyl-3-piperidones were synthesized and the stereochemistry of their reduction was studied. |
| 2. | The dependenceof stereochemistryof a series of reactions at the carbonyl center on bulk of the substituent on nitrogen was established. |
| 3. | Pure a- and e-epimers of N-ethyl- and N-isopropyl-3-piperidols were separated. |
20.
Presently, a large variety of layered materials are synthesized that are able to intercalate neutral guest molecules or to exchange inorganic and organic ions for interlayer ions. Several of these materials are also found as minerals.The intracrystalline reactivity of a few selected compounds will be described and compared to clay minerals:
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| – | - intercalation into crystalline silicic acids; |
| – | - reactions of phosphates, arsenates, and sulfates; |
| – | - reactions of titanates, niobates, and molybdates with long chain alkylammonium ions, and |
| – | - anion exchange properties of double hydroxides. |