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81.
82.
Raphanus sativus, a common cruciferous vegetable has been attributed to possess a number of pharmacological properties. Antioxidant and radical scavenging activity of R. sativus root extracted with solvents of varying polarity were evaluated using different model systems. Polyphenolic content was estimated to be in the range 13.18-63.54?mg?g?1 dry weight, with a considerable amount being obtained with polar solvents. High-performance liquid chromatography analysis indicated the presence of an array of polyphenolics. Catechin was found to be the most abundant phenolic compound in water extract and sinapic acid, the predominant phenolic compound in methanolic, ethyl acetate and hexane extracts. The methanolic extract showed significant ferric reducing ability, moderate metal chelating activity and strong radical scavenging activity. The methanolic extract could be successfully utilised as an ingredient in functional foods. However, water extract could be more pertinent to human nutrition as it contained a significant amount of catechin, which was comparable to traditional sources like green and black tea. 相似文献
83.
84.
A. M. Kofman V. E. Golender L. Ya. Leitis K. I. Rubina M. V. Shimanskaya A. B. Rozenblit 《Chemistry of Heterocyclic Compounds》1985,21(1):89-92
A computer analysis of the literature material clarified the types of activity most characteristic for pyridine derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 109–113, January, 1985. 相似文献
85.
I. Iovel' K. Rubina Yu. Popelis A. Gaukhman É. Lukevits 《Chemistry of Heterocyclic Compounds》1996,32(3):294-307
A study has been made of enantioselective hydrosilylation and reduction, by hydrogen transfer, of prochiral alkyl phenyl ketones or alkyl hetaryl ketones over various optically active catalysts. A total of 14 aromatic and heterocyclic carbinols were synthesized with preparative yields of 54–100%. The most effective catalytic systems were found to be complexes of RhCl3 and [Rh(cod)Cl]2 with the known optical inductor (S,S)-i-Pr-Pybox, with which we have obtained for the first time a series of heterocyclic secondary alcohols with an enantioselectivity of 20–63%.Latvian Institute of Organic Synthesis, Riga, LV-1006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 342–358, March, 1996. Original article submitted December 11, 1995. 相似文献
86.
Yu. Gol'dberg E. Abele K. Rubina Yu. Popelis M. Shimanska 《Chemistry of Heterocyclic Compounds》1993,29(12):1399-1404
Alkyl(2-furyl), alkyl(2-thienyl), and methyl pyridyl ketones form stoichiometric inclusion complexes with -cyclodextrins. Reduction of these complexes in aqueous solution of Na2CO3 at room temperature yields the corresponding secondary alcohols with an optical yield which attains 27%.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1621–1627, December, 1993. 相似文献
87.
Data on the production and the reactions of quinoline aldoximes and ketoximes and their derivatives are reviewed. The synthesis of new heterocycles based on quinoline oximes is examined separately. The main results from investigation of the biological activity of quinoline oximes are presented.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 163–190, February, 2005. 相似文献
88.
K. I. Rubina I. G. Iovel' Yu. Sh. Gol'dberg F. V. Shimanskaya 《Chemistry of Heterocyclic Compounds》1989,25(4):454-457
When methylazines (2-, 3-, and 4-methylpyridines, methylpyrazine) are treated with N-chlorosuccinimide they undergo successive chlorination of the methyl group to give 2-chloromethylpyridine, 2-dichloromethylpyridine, and dichloromethylpyrazine in preparative yields. 3-Dichloromethylpyridine was synthesized from pyridine-3-aldehyde and PC15. The primary chlorination products of 4-methylthiazole are 4-methyl-5-chlorothiazole and 5-chloro-4-chloromethylthiazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 543–546, April, 1989. 相似文献
89.
A novel hydrogel based on poly(sulfopropylmethacrylate) (p(SPM) with different crosslinking degrees was synthesized and characterized. The prepared hydrogels were for the first time, utilized for in situ metal nanoparticle preparation such as Ni, Co, and Cu and employed as a reaction media in catalytic reduction of 4-nitrophenol (4-NP), and 2-nitrophenol (2-NP) to 4-aminophenol and 2-aminophenol, respectively. The experimental parameters that effect reduction rates such as temperature and the amount of catalyst were investigated. The kinetics of the reduction reaction of nitro compounds under different reaction conditions were investigated to determine the activation parameter. Activation energies were found as 33.86 kJ mol? 1 and 24.96 kJ mol? 1 for 4-NP and 2-NP, respectively. It was found that hydrogel–Cu composites can provide 98% activity even at the end of the 7th repetitive usage. 相似文献
90.
Rubina K. Fleisher M. Abele E. Popelis Yu. Lukevits E. 《Russian Journal of Organic Chemistry》2003,39(7):963-967
2-Propynyl derivatives of N-methylaniline, phenol, benzenethiol, 2-pyridinethiol, 2-pyrimidinethiol, and 1,3-benzoxazole-2-thiol were synthesized. Under conditions of phase-transfer catalysis, phenyl 2-propynyl sulfide is converted into allenyl phenyl sulfide and phenyl 1-propynyl sulfide. The rearrangement mechanism was studied by the AM1 quantum-chemical method. 相似文献