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11.
Kayo Nakamura Kazuki Tsubokura Almira Kurbangalieva Yoichi Nakao Takefumi Murase Taiji Shimoda 《Journal of carbohydrate chemistry》2019,38(2):127-138
A convenient route to RIKEN click probes for glycoconjugation to the amino groups of lysines was established. N-Glycoclusters prepared with human serum albumin by the new method showed the same cell interaction profiles as those synthesized previously. The new route has thus significantly expanding the applicability to glycoconjugation and drug delivery systems. 相似文献
12.
N. F. Devyatova A. R. Kurbangalieva V. V. Yanilkin G. A. Chmutova 《Russian Chemical Bulletin》2009,58(5):908-919
The electrochemical oxidation of aryl- and alkylthio derivatives of mucochloric acid (3,4-dichloro-5-hydroxyfuran-2(5H)-one) in MeCN-Bu4NBF4 (0.1 mol L−1) was investigated. It was shown that all sulfides are electrochemically active, from one to five oxidation steps of sulfur-containing
groups were observed for them. The ease and direction of oxidation of the thio group depend on its nature and position in
the furanone ring. 3-Substituted 2(5H)-furanones possess the lowest oxidation potential. 4-Substituted 2(5H)-furanones are predominantly oxidized to sulfoxides, 5-aryl- and -alkylthio derivatives undergo fragmentation to give mucochloric
acid, and 3-arylthio derivative gives complex unidentified mixture of products. In the case of 3,4-bis(4-methylphenylthio)
derivative, the oxidation product of the arylthio group at the 3 position to the corresponding sulfoxide was isolated. Based
on the data from cyclic voltammetry with different concentrations of a substrate and water added, the results of preparative
electrolysis and quantum chemical calculations, possible mechanisms of electrochemical oxidation of mucochloric acid-derived
sulfides are discussed. The initial common step is a reversible single-electron transfer from the substrate molecule to form
highly reactive radical cation. 相似文献
13.
L. Z. Latypova E. Sh. Saigitbatalova D. R. Chulakova O. A. Lodochnikova A. R. Kurbangalieva E. A. Berdnikov G. A. Chmutova 《Russian Journal of Organic Chemistry》2014,50(4):521-534
A number of 4- and 5-R-sulfanylfuran-2(5H)-one derivatives were synthesized, and their oxidation with various reagents was studied. The corresponding sulfones were obtained using hydrogen peroxide in acetic acid. 4-R-sulfanyl derivatives were selectively oxidized to sulfoxides with m-chloroperoxybenzoic acid. The molecular and crystal structures of some new sulfones and sulfoxides were determined by X-ray analysis. 相似文献
14.
15.
Dilyara R. Chulakova Ambara R. Pradipta Olga A. Lodochnikova Danil R. Kuznetsov Kseniya S. Bulygina Ivan S. Smirnov Konstantin S. Usachev Liliya Z. Latypova Almira R. Kurbangalieva Katsunori Tanaka 《化学:亚洲杂志》2019,14(22):4048-4054
The chiral substituted 1,5‐diazacyclooctane (1,5‐DACO) is of considerable importance and has attracted attention from a wide range of fields due to their unique chemical and biological properties. Despite the application potential, further study has not been optimized due to difficulties in their synthetic accessibility. Here, we report that the 1,5‐DACO bearing a chiral auxiliary obtained from the formal [4+4] cycloaddition of N‐alkyl‐α,β‐unsaturated imines can be further derivatized by nucleophilic alkylation to give various chiral substituted 1,5‐DACO derivatives. The removal of the chiral auxiliary was effectively carried out using hydrogenation over Pearlman's catalyst. This methodology allows the production of a broad range of unprecedented optically active 2,6‐dialkyl‐1,5‐DACO, which could not be accessed by other methods. 相似文献
16.
Chmutova G. A. Kurbangalieva A. R. Vedernikov A. N. 《Russian Journal of General Chemistry》2001,71(5):780-785
The relative stability of tautomeric forms of 1-methyl-substituted heteropyrazolones (O, S, Se) and their gas-phase acidity were estimated by DFT calculations with various basis sets and methods of geometry optimization. The electron correlation effects make an appreciable contribution to the Gibbs free energies of their tautomers and anions, especially those containing the heavy atoms. The qualitative pattern of tautomerism in pyrazolones is essentially similar to that obtained by semiempirical and nonempirical RHF calculations: The most stable is the CH form. For hetero analogs, consideration of electron correlations effects increases the relative stability of SH (SeH) forms. The series of relative acidity of the compounds depending on the heteroatom is preserved (Se O). 相似文献
17.
A. R. Kurbangalieva N. F. Devyatova L. S. Kosolapova O. A. Lodochnikova E. A. Berdnikov I. A. Litvinov G. A. Chmutova 《Russian Chemical Bulletin》2009,58(1):126-133
The stable products of reactions of mucochloric acid and some of its ethers with 2-mer-captoacetic acid were synthesized and
characterized. The variation of experimental conditions allowed targeted introduction of a sulfur- containing fragment into
particular position of the heterocycle: the reaction in aqueous potassium hydroxide gives 3-substituted 2(5H)-furanone the triethylamine additive in nonaqueous solvents facilitates the formation of 4-substituted products, and acid
catalysis results in the replacement of the hydroxy (methoxy) group at C(5). (3,4-Dichloro-2-oxo-2,5-dihydrofuran-5-ylthio)ethanoic
acid and (3-chloro-5-hydroxy-2oxo-2,5dihydrofuran-4-ylthio)ethanoic acid were characterized by X-ray diffraction; their crystal
and gas-phase structures were discussed. The 5-monosubstituted product crystallizes as a racemate, while 4monosubstituted
product, as a conglomerate. 相似文献
18.
L. Z. Latypova V. V. Yanilkin A. R. Kurbangalieva E. A. Berdnikov G. A. Chmutova 《Russian Chemical Bulletin》2012,61(3):568-581
5-Alkoxy-3-chloro-2(5H)-furanones were synthesized by the electrochemical reduction of 5-alkoxy derivatives of mucochloric acid in acetonitrile on the lead electrode in the presence of acetic acid as a proton donor. A combined analysis of the experimental data and quantum chemical calculation of intermediates indicates the EE D C mechanism of reduction, including the tandem transfer of two electrons with chloride ion elimination at the stage of transfer of the second electron and protonation. 相似文献
19.
O. A. Lodochnikova L. Z. Latypova R. M. Khakimov A. R. Kurbangalieva D. B. Krivolapov I. A. Litvinov 《Journal of Structural Chemistry》2013,54(1):213-216
The X-ray diffraction study of cis-2,3-dichlorobuth-2-ene-1,4-diol (3) obtained by the reduction of 3,4-dichloro-5-ethoxy- and 5-isopropoxi-2(5H)-furanones with lithium aluminum hydride is performed. The crystals of compound 3 are trigonal: a = b = 15.746(9) Å, c = 6.848(4) Å; V = 1470.5(15) Å3, space group P31, Z = 9 (three independent molecules). Independent molecules have identical planar conformation, and hydroxyl groups are located on different sides of the multiple bond plane. The supramolecular motif of the crystal is spirals about the threefold screw axes; the neighboring spirals are linked by OH…O hydrogen bonds. 相似文献
20.
Movchan A. I. Kurbangalieva A. R. Kataeva O. N. Litvinov I. A. Chmutova G. A. 《Russian Journal of General Chemistry》2003,73(7):1130-1136
A single-crystal X-ray diffraction study showed that 1-phenyl-3-methyl-4-formyl-4,5-dihydropyrazol-5-one occurs in the solid phase as two conformers of the NH tautomer. The acidity and basicity constants of 1-phenyl-3-methyl-4-formyl-4,5-dihydropyrazol-5-one and its analog, -5-thione, in 50% aqueous dioxane were measured. PM3 calculations qualitatively explan the differences in the tautomerism and acid-base properties of 4-formylpyrazolone (-pyrazolethione) and the corresponding compounds without the formyl substituent. 相似文献