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1.
T. N. Deshko A. V. Kamernitskii G. A. Kogan A. M. Turuta T. K. Ustynyuk T. M. Fadeeva 《Russian Chemical Bulletin》1976,25(12):2524-2528
| 1. | Study has been made of the circular dichroism spectra of 20-ketosteroids containing a three-membered ring (methylene, epoxide, episulfide, or aziridine) in the -position with respect to the keto group. |
| 2. | The observed n* and * transition Cotton effects have been correlated with the preferred conformation of the molecule. |
2.
A. M. Turuta A. V. Kamernitskii T. M. Fadeeva A. Pabinger V. S. Bogdanov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(10):2156-2161
| 1. | The transformation of 21-0,N-isopropylidene derivatives of 16,17-epiminopregn-5-ene-2,21-diol-20-one into 20-0,N-isopropylidene derivatives of 16,17-epiminopregn-5-ene-3,20-diol-20-one was discovered, and, based on this, a new variant of the synthesis of 16,17-epiminopregn-5-ene-3,21-diol-20-one-3,21-diacetate was proposed. |
| 2. | A new class of steroids with additional tetrahydrofuran and 1,3 -imidazolidine-2thione rings E and F, respectively, was synthesized. |
3.
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. |
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5.
R. R. Shagidullin A. V. Chernova I. A. Nuretdinov G. M. Doroshkina E. V. Bayandina 《Russian Chemical Bulletin》1976,25(1):174-177
| 1. | Absorption bands were observed in the UV spectra of saturated selenophosphoryl compounds that were attributed to the *, n *, and n - * transitions in the selenophosphoryl group. |
| 2. | It was proposed to use the UV spectroscopy method to study the seleno-selenol isomerism in organophosphorus compounds. |
6.
K. N. Makarov T. N. Abroskina Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(4):922-924
| 1. | The cesium chloride adducts with perfluoroacetone, 1-methyl-2-oxaperfluoroenanthyl fluoride, and perfluoroisobutylene react smoothly with symmetrical dichlorodimethyl ether, replacing both chlorine atoms, with the formation of the corresponding ethers. |
| 2. | The interaction of,-dihydroperfluoroamyl alcoholate with symmetrical dichlorodimethyl ether leads to the replacement of both chlorine atoms, with the formation of the corresponding ether. |
| 3. | The reaction of perfluoro-t-butylanion with tris(chloromethyl)amine leads to tris-(1,1-dihydro-perfluoroneopentyl) amine. |
| 4. | Perfluoro-t-butylanion replaces only one chlorine atom in the molecule of unsymmetrical di-chlorodimethyl ether, forming-chloro- -perfluoro-t-butyldimethyl ether. |
7.
Kozlovskii A. G. Arinbasarov M. U. Yakovlev G. I. Zyakun A. M. Adanin V. M. 《Russian Chemical Bulletin》1976,25(5):1115-1119
| 1. | An earlier unknown metabolite ofPseudomonas aeruginosa, strain A197, 2-(n-1-heptenyl)-4-quinolone, was isolated. |
| 2. | The main components of the total mixture of alkaloids produced byPseudomonas aeruginosa strain A197 are 2-n-nonyl-4-quinolone (pseudane-IX), 2-n-heptyl-4-quinolone (pseudane-VII), 2-(n-1-nonenyl)-4-quinolone (1pseudene-IX), and 2-(n-1-heptenyl)-4-quinolone (1-pseudene-VII). |
| 3. | The synthesis of 2-(n-1 -heptenyl)- 4 -quinolones was carried out. |
8.
Yu. N. Belokon' V. A. Karginov V. I. Tararov V. M. Belikov 《Russian Chemical Bulletin》1976,25(1):54-57
| 1. | Diastereomeric complexes of - and -bis-[N-salicylidene-S-alaninato]chromate(III)K and - and -bis-[N-salicylidene-S-valinato]chromate(III)K were synthesized and chromatographically separated. The absolute configuration of the diastereomers was demonstrated with the aid of ORD curves. |
| 2. | The kinetics of the epimerization of - and -bis-[N-salicylidene-S-alaninato]chromate(III)K and - and -bis-[N-salicylidene-S-valinato]chromate(III)K under the action of OH– ions in water was studied: it was shown that the proton of the amino acid fragment is less labile in these complexes than in the isostructural complexes of Co3+ and Rh3+. |
9.
V. N. Odinokov V. K. Ignatyuk G. A. Tolstikov Yu. B. Monakov A. A. Berg A. M. Shakirova S. R. Rafikov A. A. Berlin 《Russian Chemical Bulletin》1976,25(7):1475-1481
| 1. | Liquid cis-1,4-oligodien-1,3-, -glycols have been prepared by the partial ozonolysis of cis-1,4-polydienes-1,3 in inert solvents containing methanol as an active additive in the amount of 1 to 10 moles per 1 mole of ozonide and subsequent reduction of the peroxide ozonolysis products by LiAlH4. |
| 2. | A method is proposed for the determination of the molecular weights of the oligomeric ,-glycols by use of the PMR spectra of their bis(trimethylsilyl) ethers, and the molecular weight distributions of the oligomeric, -glyeols obtained have been established. |
10.
| 1. | The corresponding 1,3-bis[-(p-toluenesulfonamido)alkyl]uracils are formed as a result of the reaction of 1, 3-bis(-bromoalkyl)uracils and the Na salt of p-toluenesulfamide. |
| 2. | Interaction of l-(-bromobutyl)uracil with p-toluenesulfamide in a medium of n-butanol leads to formation of 9,18,19,20-tetraoxo-1,6,10,15-tetraazatricyclo[13.3.1.16.10]-eicosa-7, I6-diene,l-(-hydroxybutyl)-2-butoxypyrimid-4-one, and l-(-hydroxybutyl)-2-p-toluenesulfonamidopyrimid-4-one. |
11.
Z. V. Todres G. Ts. Ovsepyan E. A. Ionina A. Yu. Kosnikov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(8):1651-1656
| 1. | o-Dinitrobenzene dianion reacts with p-dimethylaminobenzenediazonium cation to give 2-nitro-4-dimethylaminoazobenzene. |
| 2. | o-Dinitrobenzene anion-radical reacts with benzenediazonium cations bearing a dimethylamino-or nitro-group in the para-position, to give 3-nitro-4-hydroxy-4-dimethylamino-azobenzene and 3,4-dinitro-4-hydroxyazobenzene respectively. |
| 3. | In the case of the 4-methoxybenzenediazonium cation, reaction with the o-dinitrobenzene anion-radical affords 4-methoxy-3-(2-nitrophenyl--azoxy)-4-hydroxyazobenzene, the structure of which has been established by x-ray diffraction analysis. |
| 4. | These azo-compounds are formed in solvents which favor the stability of ion pairs of the dianion or anion-radical of o-dinitrobenzene with potassium cations. Dissociation of the ion pairs results in the occurrence of electron transfer only. |
12.
V. I. Reznikov V. Yu. Zel'venskii L. F. Rybakova E. M. Panov O. M. Khodkevich A. F. Volkov L. K. Vasyanina K. A. Kocheshkov 《Russian Chemical Bulletin》1976,25(7):1493-1498
| 1. | m-Bromo-,-difluoro--chlorostyrene was synthesized and the conditions for the analytical and preparative separation of the cis and trans isomers were determined. They were isolated with a purity of 99.8% as were the isomers of the previously synthesized, - difluoro--chlorostyrene. |
| 2. | The structure of the isomers was confirmed by NMR, NQR, and IR spectroscopies. |
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14.
I. V. Kozhevnikov A. I. Tsyganok M. N. Timofeeva S. M. Kulikov V. N. Sidelnikov 《Reaction Kinetics and Catalysis Letters》1992,46(1):17-23
Liquid-phase alkylation of p-tert-butylphenol (TBP) and p-cresol by olefins and benzyl chloride in the presence of solid heteropoly acids (HPA) H3PW12O40 and 25% H3PW12O40/SiO2 at 100–150°C provides high yields of mono- and disubstituted products. HPAs are more active than H2SO4, easily separated from the reaction mixture and can be used repeatedly. -- () - () H3PW12O40 25% H3PW12O40/SiO2 100–150°C - - . , H2SO4, - - . 相似文献
15.
After light irradiation of oil films on water surface the autoxidation process has been found to be of nonsteady auto-oscillatory character, which can be observed in rate oscillations of O2 absorption. Also recorded have been intensity oscillations of the EPR signal from the radical counter added into an oil sample. Complex dynamics of autoxidation can be due to an autocatalytic process involving the participation of peroxides accumulated in oil during photooxidation., , , , O2. , , . , , . 相似文献
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17.
A. M. Kritsyn L. I. Kolobushkina S. N. Mikhailov V. L. Florent'ev 《Russian Chemical Bulletin》1976,25(2):384-387
| 1. | 9-(3-Aminopropyl)adenine, racemic 9-(2-hydroxy-3-amitiopropyl)adenie and its (R)-enantiomer, and 9-(2-hydroxy-3-methylaminopropyl)adenine were synthesized. |
| 2. | A study was made of the NMR spectra of the reaction products of the -tosyloxyalkyl derivatives of uracil and thymine with ammonia and methylamine. Theories were expressed regarding the structure of the formed compounds. |
18.
Thermodynamic studies of clathrate hydrates, mainly of structures I and II, are considered in this review which is based on 147 references. There are two main subjects. The first is the host lattice energy and the guest-host interaction energy, both of these quantities being related to the enthalpy of dissociation and composition of the hydrates. The second subject concerns orientational ordering phenomena occurring in both host and guest, as reflected in the low temperature heat capacity. The classical theoretical treatment of clathrate formation has been reconsidered on the basis of recent experimental results. Particular emphasis has been given to orientational ordering since this topic is undoubtedly central to clarifying the nature of clathrate hydrates.Ausgehend von 147 Literaturangaben wurden in diesem Review thermodynamische Untersuchungen von Klathrathydraten hauptsächlich der Struktur I und II betrachtet. Es gibt zwei Hauptaugenmerke. Als erstes die Wirtsgitterenergie und die Gast-Wirt-Wechselwirkungsenergie, beide bezogen auf die Dissoziationsenthalpie und die Bildungsenthalpie der Hydrate. Das zweite Hauptaugenmerk betrifft Orientierungs-Konditionierungserscheinungen sowohl in Wirt als auch Gast, wie in den Wärmekapazitäten bei niedrigen Temperaturen widergespiegelt wird. Auf der Basis jüngster experimenteller Ergebnisse wurde die klassische theoretische Betrachtung über die Bildung von Klathraten überprüft. Der Orientierung-Konditionierung wurde besonderer Nachdruck verliehen, da dies zweifellos eine entscheidende Rolle bei der Klärung der Natur der Klathrathydrate spielt. 147 I II. . «» « — », . «» « », . . , .
Contribution No. 155 from the Chemical Thermodynamics Laboratory. 相似文献
Contribution No. 155 from the Chemical Thermodynamics Laboratory. 相似文献
19.
| 1. | In the nucleophilic addition of alcohols to alkylacetylenes (methyl- and tert-butyl-), the regiospecificity of the attack of alkoxide converts to regiose lectivity with the increasing steric requirements of the substituent in the alkyne and of the attacking nucleophile. |
| 2. | The reaction leading to the adduct takes place with strict steric specificity by a nucleophilic mechanism of 1, 2-anti-addition with the formation of cis isomers; this behavior is independent of steric hindrances. |
20.
| 1. | The structure of the isocyanate functional group in organic isocyanates in the crystalline state is analogous to that in the gas phase. |
| 2. | The isocyanate group (H)C1-N=C2=O exists in a trans conformation in all three of the isocyanates studied. |
| 3. | The lamellar packing characteristic of ,-naphthalenediisocyanate molecules may be assigned to a structural subclass of naphthalene ¯1, namely, P(x)P21/b. |