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1.
N. V. Zakatova D. R. Minkhadzhidinova M. A. Nadzhafova R. F. D'yachkovskaya N. P. Koaovalova V. A. Sharpatyi 《Russian Chemical Bulletin》1976,25(2):434-436
| 1. | We determined the reactivity of some nitrogen bases, and of a number of amino acids and bis-(diazoacetyl)alkyl derivatives toward the electron at 77°K. |
| 2. | The effect of the pH at 77°K as established on the yield of the deamination process and the reactivity of the studied amino acids toward the electron. |
| 3. | It was found that the yield for the deamination of glutamic acid is increased in the presence of inositol (acceptor of OH radicals). |
2.
| 1. | Study has been made of the kinetics of the-elimination of alcohol from 3-carbethoxy-4-ethoxy-2-pentanone in benzene and under the catalytic action of acetic acid. |
| 2. | This reaction involves formation of a complex between substrate and acetic acid. |
| 3. | The equilibrium constant for the reaction of forming the complex between substrate and acetic acid, and the rate constant for complex formation, have both been determined. |
3.
| 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. |
4.
B. E. Ivanov L. A. Valitova V. I. Gaidai T. G. Bykova N. I. Kuchma S. V. Samurina 《Russian Chemical Bulletin》1976,25(11):2386-2389
| 1. | An intermediate alkoxyphosphorane with two pentacoordinated phosphorus atoms was isolated and characterized during the reaction of 2,5-bis(diethylaminomethyl)hydroquinone with trialkyl phosphites. |
| 2. | A method has been developed for the synthesis of phosphorylated dihydric phenols. |
| 3. | The triethylether of 3-ethoxy-6-hydroxy-1,4-xylyenediphosphonic acid was prepared by the interaction of 2,5-bis(diethylaminomethyl)hydroquinone with diethylphosphorous acid in the presence of triethyl phosphite. |
5.
A. S. Vzdykhan'ko V. V. Glushenko M. N. Mirzayanova A. Ya. Khorlin 《Russian Chemical Bulletin》1976,25(3):689-691
| 1. | 2-O-p-Nitrophenyl-N-acetyl--neuraminoside, a suitable substrate for the kinetic study of neuraminidases, was synthesized, and its stability was studied. |
| 2. | The sodium salt of this ketoside is stable during prolonged storage. |
6.
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. |
7.
| 1. | Potentiometric titration in nitromethane at 25°C has been used to determine dissociation constants for 16 mono-substituted benzoic acids. |
| 2. | Brönsted and Hammett equations have been set up for the compound series under study here. |
| 3. | The data of the literature have been used to evaluate the nitromethane autoprotolysis constant, pKS24. |
| 4. | The relative differentiating action of nitromethane with respect to other solvents has been evaluated from the slopes of the Brönsted and Hammett plots and the values of the autoprotolysis constant. The differentiating action of nitromethane with respect to acids is greater than that of acids with respect to alcohols and acetone, but less than that of DMSO, acetonitrile, and DMF. |
| 5. | Study has been made of the dissociation of the aminobenzoic acids in nitromethane. Solutions of p-aminobenzoic acid are free of zwitterions, while solutions of the m-aminobenzoic acid contain these ions to the extent of 50%. |
8.
A. Teies Gonsalo A. I. Donskikh V. N. Kulagin Yu. V. Moiseev G. M. Tseitlin 《Russian Chemical Bulletin》1976,25(5):1156-1158
| 1. | The hydrolysis rate of N-benzoylanthranilic acid was studied at a KOH concentration of 2.2–44.6% and a temperature of 25–95°. |
| 2. | The limiting step of the process is the reaction of the singly ionized form of the reagent with a molecule of water. |
| 3. | The equilibrium constant for the addition of hydroxyl ion to the carbonyl atom of the amido group of N-benzoylanthranilic acid is 267, and the true rate constant for the reaction of the ionized form with a molecule of H2O at 25° is 0.13 min–1. |
9.
L. F. Chertanova G. A. Marchenko A. A. Gazikasheva Yu. T. Struchkov V. F. Sopin L. N. Punegova A. S. Mukhametzyanov 《Russian Chemical Bulletin》1989,38(2):250-253
| 1. | The planar alkoxydiazinoxide fragments are shown to have the Z-configuration and be orthogonal to each other by an x-ray structure study of a series of alkoxydiazinoxides. |
| 2. | In the oxydiazinoxide fragments, p- conjugation occurs. |
| 3. | The molecules of the compounds in the crystals studied are joined by hydrogen bonds. |
10.
É. D. Filippova N. D. Mitrofanova L. I. Martynenko V. I. Spitsyn 《Russian Chemical Bulletin》1976,25(1):4-7
| 1. | Complexes of the REE, Y, and Sc with hydroxyethylethylenediaminetriacetic acid have been isolated in solid form. The hydrate compositions of the complexes have been determined. |
| 2. | The La and Pr complexes form hydrates of different compositions. The LnL hydrates form slightly nonisostructural groups in the series La-Lu. |
| 3. | According to thermographic analysis data, the hydrate water in the LnL·nH2O complexes of different hydrate compositions is not bonded with the same firmness. |
11.
T. Ya. Medved' N. M. Dyatlova V. P. Markhaeva M. V. Rudomino N. V. Churilina Yu. M. Polikarpov M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(5):992-997
| 1. | New organophosphorus complexing agents were synthesized: ethylenediamino-N,N'-diethylphosphonic, N,N-dimethylethylenediamino-N,N-dimethylphosphonic, and N,N-dimethylethylenediamino-N, N-diethylphosphonic acids and also the iodomethylate of the last acid. |
| 2. | The acid dissociation constants for these compounds and the stability constants for their complexes with nickel, copper, dysprosium, and uranyl ions were determined. |
12.
| 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. |
13.
| 1. | The previously unknown aminooxyalkylcelluloses have been synthesized by alkylation of cellulose with N-substituted -haloalkylhydroxylamines. |
| 2. | The prepared aminooxyalkylcelluloses are weak ion-exchangers, readily react with many classes of organic compounds, and are stable during storage. |
| 3. | Methods have been developed for the preparation of aminooxyalkylcelluloses with different lengths of the pendant H2NO group on the polysaccharide framework. |
| 4. | Sorbents were prepared, based on the aminooxyalkylcelluloses, which contained a covalently bonded coenzyme (pyridoxal-5-phosphate), a substrate (-ketoglutaric acid) and functional groups, able to react with certain functional groups of biopolymers. |
14.
Z. G. Aliev L. O. Atovmyan E. A. Saratovskikh V. I. Krinichnii V. G. Kartsev 《Russian Chemical Bulletin》1988,37(11):2246-2252
| 1. | Treatment of chloropicolinic acids with aqueous solutions of various copper salts in alcohol media results in the formation of complexes of composition 21. |
| 2. | The structures of the newly synthesized complexes have been shown to be identical in the solid state and in solution. |
| 3. | Diverse modes of coordination of picolinic acid derivatives have been demonstrated; this may be one of the factors responsible for the ease of formation of metallocomplexes in biological systems, and thus may be responsible for the high biological activity (of picolinic acid derivatives). |
15.
A. A. Onishchenko O. S. Reshetova V. P. Gorelik O. A. Luk'yanov V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(5):1135-1137
| 1. | n-Nitro-p-toluenesulfonic acid N-nitroamide adds to olefin oxides to give N--hydroxyalkylation products. The direction of the addition to monosubstituted oxides is such that the nitroamide anion adds to the most sterically available carbon atom. |
| 2. | m-Nitro-p-toluenesulfonic acid N-nitroamide reacts with unsubstituted ethylenimine to give the ethylenimine salt of the nitrosulfonamide. |
| 3. | m-Nitro-p-toluenesulfonic acid N-nitroamide reacts with an N-acylated ethylenimine or trimethylenimine with ring opening and the respective formation of N-- or N--amidoalkylation products. |
16.
P. Ya. Bayushkin E. N. Gladyshev G. A. Razuvaev E. A. Emelina 《Russian Chemical Bulletin》1976,25(2):431-433
| 1. | The first stable compound with an O-Hg-Ge grouping was obtained by the reaction of 4,6-ditert-butyl-1,2-benzoquinone with bis(triisopropylgermyl)mercury. |
| 2. | A study was made of the photodecomposition of 1-triisopropylgermyloxy-2-triisopropylgermyl-mercuroxy-3,5-di-tert-butylbenzene, and also of its reaction with hydrochloric acid and ethylmercury chloride. |
17.
I. V. Anonimova N. A. Chadaeva L. K. Yuldasheva S. G. Vul'fson A. N. Vereshchagin B. A. Arbuzov 《Russian Chemical Bulletin》1976,25(12):2519-2524
| 1. | It has been shown that 2-bromo-l,3,2-dioxaarsenanes exist in chair conformation with axially oriented As-Br bonds. |
| 2. | Polarity and polarizability parameters have been found for the As-O and As-Br bonds in 2-bromo-l,3,2-dioxaarsenanes. |
| 3. | The so-called -effect is stronger in the O2AsBr group than in the O2AsCl group. |
18.
| 1. | 1,2-Oxathiolan-5-one-2-oxides are readily cleaved by nucleophiles (H2O, ROH, HNR2) under mild conditions at the O-CO bond only, with the formation of the -(hydroxysulfinyl)-alkanoic acid derivatives. |
| 2. | 2,1-Benzoxathiol-3-one-1-oxide is cleaved by alcohols at both the O-CO and the O-SO bonds to give the unstable monoesters at the carboxyl and sulfinyl groups. |
| 3. | Unlike 2,1-benzoxathiol-3-one-1-oxide, 1,2-oxathiolan-5-one-2-oxides on boiling with excess alcohols give -(hydroxysulfinyl)alkanoic acid bisesters. |
19.
| 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. |
20.
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. |