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1.
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. |
2.
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+. |
3.
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. |
4.
| 1. | We accomplished the stereospecific cis-opening of the aziridine ring of 16,17-epiminopregn-5-en-3-ol-20-one by treatment with thiocyanic acid in the presence of a reagent on the carbonyl group, which was accompanied by cyclization with the formation of 2-aminopregn-5-en-3-ol-20-one[16,17-d]thiazoline. |
| 2. | Employing IR and UV spectroscopy, a study was made of the structure and tautomeric equilibrium of the 2aminothiazolines and their N-acetylated derivatives; all of the obtained compounds represent a mixture of tautomers. |
5.
R. R. Shagidullin Jr. R. R. Shagidullin K. M. Enikeev A. N. Karaseva G. A. Bakaleinik 《Russian Chemical Bulletin》1988,37(7):1374-1378
| 1. | In the IR and Raman spectra of 3,3,6-trimethyl-6-hydroxy-7-chlorocyclohept-1-en-5-one when the phase and other conditions are varied there are indications of a conformational equilibrium involving at least three molecular forms. |
| 2. | On the basis of this information as well as PMR spectra and examination of models it follows that in the liquid state the chair and twist boat forms occur. Similar results have also been obtained for 3,6-trimethyl-6-hydroxy-7-methoxycyclohept-1-en-5-one, in which hindered rotation about the C-OMe axis is also observed. |
| 3. | Analysis of the spectra and models of 3,3,6-trimethyl-6,7-epoxycyclohept-1-en-5-ol and 3,3,6-trimethyl-6,7-epoxycyclohepten-5-one molecules has provided a conclusion about their possible conformations. |
6.
Zh. A. Krasnaya T. S. Stytsenko V. S. Bogdanov A. S. Dvornikov 《Russian Chemical Bulletin》1989,38(6):1206-1218
| 1. | Dienic-dimethylaminocarbonyl compounds were synthesized containing a Br, OEt, or CN substituent in the -position.-Dimethylamino--cyanodienones are found in the open form and do not cyclize to 2H-pyrans. |
| 2. | The existence of a dynamic equilibrium was established between-dimethylamino--bromodienone (or-dimethylamino--ethoxydienone) and 3-bromo-2-dimethylaminopyran (or 3-ethoxy-2-dimethylaminopyran), which depends on the solvent and temperature. |
| 3. | The equilibrium is shifted toward the 2H-pyran with increasing bulk of the solvent in the -position of the-dimethylaminodienone. |
| 4. | The 2H-pyrans upon the action of UV light undergo reversible dissociation of the C-O bond and isomerize to-aminodienones. |
7.
| 1. | -Methyl--functionally substituted conjugated trienones and -phenyl dienones were synthesized. |
| 2. | -Methyl--functionally substituted trienones exist in the open form, while -phenyl dienones exist in the form of 2H-pyrans. |
8.
G. V. Kryshtal' G. M. Kursonova V. F. Kucherov L. A. Yanovskaya 《Russian Chemical Bulletin》1976,25(3):652-654
| 1. | ,-Dichloropolyene aldehydes react with acetone cyanohydrin in the presence of triethylamine to give -chloropolyenoic esters. |
| 2. | A new method has been developed for the synthesis of Cl(CH = CH)nCOOR, where n = 2 and 3. |
9.
L. F. Godunova E. S. Levitina E. I. Karpeiskaya E. I. Klabunovskii Yu. L. Yagupol'skii M. T. Kolycheva 《Russian Chemical Bulletin》1989,38(2):351-354
| 1. | Catalytic reductive aminolysis of the azalactones of N-acyl-p-difluoromethoxy--aminocinnamic acid in dimethoxyethane, isopropanol, and tert-butanol proceeds stereoselectively, leading to the -phenylethylamides of N-acyl-p-difluoromethoxyphenylalanine with a 3–55% excess of the S,S-diastereomer. |
| 2. | Replacement of dimethoxyethane by isopropanol or tert-butanol leads to an increase in the stereoselectivity of the process. |
| 3. | Hydrogenation of the S-(+)--phenylethylamide of N-acyl-p-difluoromethoxy--aminocinnamic acid proceeds stereoselectively, and leads to production of the -phenylethylamide of N-acyl-p-difluoromethoxyphenylalanine with a 9–18% excess of the R,S-diastereomer. |
10.
L. Kh. Freidlin L. I. Gvinter V. A. Zamureenko L. N. Suvorova 《Russian Chemical Bulletin》1976,25(4):795-797
| 1. | Intermediate enol formation has been registered by deuterium exchange in the hydrogenation products of, -unsaturated ketones on Co/C and Rh/C, indicating 1,4 addition of hydrogen to the enone system. |
| 2. | The presence of 1,4 hydrogen addition to,-unsaturated ketones is determined by the nature of the catalyst; Pd/C does not catalyze this process route. |
| 3. | Modification of Pd catalysts with cadmium changes their orienting action and selectivity in favor of 1,4 hydrogen addition with intermediate enol formation. |
11.
V. F. Tarasov E. N. Step L. A. Margulis A. L. Buchachenko 《Russian Chemical Bulletin》1989,38(2):221-225
| 1. | The reaction of disproportionation of a geminal radical pair formed in photodissociation of desoxybenzoins is magnetic- and isotope-selective to the same degree as the recombination reaction. |
| 2. | The efficiency of separation of12C and13C isotopes based on the magnetic isotope effect decreases in the order desoxybenzoin, -methyldesoxybenzoin, and ,-dimethyldesoxybenzoin during photolysis, which is due to an increase in the probability of isotope-selective disproportionation of geminal radical pairs. |
12.
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. |
13.
| 1. | The conformation and geometric parameters of isomeric macrocyclic ketolactones including a thiophene ring have been determined: 5-oxa-[10]--cyclothienedione-1,4 (I) and 6-oxa-[10]--cyclothienedione-1,5(II). |
| 2. | The position of the lactone group in the ansa-compound (II) leads to a less stressed macrocycle, in comparison with (I). |
14.
| 1. | A practicable method for the synthesis of vicinal bis(difluoramino)-containing carboxylic acids by reacting tetrafluorohydrazine with unsaturated acids has been developed. |
| 2. | ,-Bis(difluoramino)carboxylic acids are unstable and undergo decarboxylation followed by dehydrofluorination. |
| 3. | ,-Bis(difluoramino)carboxylic acids are fairly stable and in some cases display the properties of ordinary carboxylic acids. |
15.
| 1. | It has been shown that, the lifetime of a negatively charged molecular ion, is related to the following molecular parameters: the electron affinity, the electronic-vibrational interaction constants, the active vibration frequencies, and the value of the nonadiabaticity. depends critically on the electron affinity, increasing monotonically as the latter rises. |
| 2. | The rate of ion breakdown along each of the decomposition channels increases with an increase in the energy of the impinging electron and/or the initial vibrational energy of the molecule. There is an increase in the number of breakdown channels under these same conditions, but it is not large. |
| 3. | The lifetime of the negatively charged molecular ion can be used to get a highly precise determination of the electron affinity of the molecule. |
| 4. | The distribution of emitted electrons over energies is essentially exponential, the characteristic width being given by /ln(E 1/E 1 Ne).). |
16.
| 1. | Alkylarylketiminoboranes react with nitriles to form boron -diiminates, whose structure has been determined by UV, IR, PMR, and boron-11 NMR spectroscopy. |
| 2. | Depending on their structure, boron -diiminates are hydrolyzed in an acid medium with the formation of either boron -diketonates, or -diketones. |
| 3. | During the reaction of boron -diiminates with HCl or HBF4, boronium salts are formed with -diimines as ligands. |
17.
V. I. Kadentsev B. I. Maksimova O. S. Chizhov L. A. Yanovskaya 《Russian Chemical Bulletin》1989,38(4):874-876
| 1. | The -lactone is more stable than the -lactone both relative to electron impact and upon chemical ionization. |
| 2. | The major pathways for fragmentation upon electron impact for the -lactone are related to decomposition of the cyclohexane ring, while, in the case of -lactone, fragmentation of the oxygen-containing part of the molecule also occurs in addition to these processes. |
18.
V. A. Ermolaeva G. A. Marchenko V. I. Markovskii V. I. Slovetskii S. S. Novikov 《Russian Chemical Bulletin》1976,25(12):2495-2498
| 1. | Study has been made of the IR spectra of N--polynitroalkylhydrazine derivatives, band assignments being made for stretching vibrations in the NH, C=O, and NO2 groups. |
| 2. | Integral intensities for NO2 antisymmetrical stretching absorption bands are additive. Splitting of these bands is characteristic of nitro compounds containing a hydrazine radical in the -position with respect to the nitro group. |
| 3. | It has been shown that intermolecular hydrogen bonding exists in the N--polynitro-alkylhydrazines, in the crystalline state and in concentrated solution. |
19.
Yu. V. Maksimov P. Ya. Kolotyrkin Yu. V. Baldokhin A. V. Krylova 《Russian Chemical Bulletin》1989,38(7):1344-1349
| 1. | The protective layer of microcrystalline iron consists of crystallites of hematite magnetically ordered at 20C and 0.1 m in size, and the phase composition of the surface and bulk of the sample is qualitatively the same in all conditions of oxidation. |
| 2. | The passivating film of the promoted catalyst of synthesis of ammonia is formed from small clusters of iron oxide with an effective size of 0.005–0.01 m; the composition of the surface and bulk of the stabilized catalyst is qualitatively different. |
| 3. | The role of the defects in the promoted catalyst in the mechanism of formation of oxide clusters was discussed. |
20.
| 1. | Substituted thiazoles are formed when N-acyl--aminoketones are heated with thioacetic acid and ZnCl2 in ether dioxane or ethyl acetate. |
| 2. | The reaction of acetamidoacetone with thioacetic acid and ZnCl2 at 20° leads to 2,5-dimethyl-5-acetylmercapto-2-thiazoline. |
| 3. | -Formamidoketones are formed when-aminoketone hydrochlorides are heated with orthoformic ester. |