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751.
S. V. Tomshich R. P. Gorshkova Yu. N. El'kin Yu. S. Ovodov 《Chemistry of Natural Compounds》1976,11(5):594-599
Summary Using the chromato-mass spectrometry of the methylated sugars formed in the hydrolysis of the fully methylated lipopolysaccharide fromYersinia pseudotuberculosis of type IB the nature of the glycosidic bonds between the monosaccharide residues has been established. The hapten formed in the partial hydrolysis of the lipopolysaccharide has also been studied by methylation. The results obtained have confirmed the results of an investigation of the methylated lipopolysaccharide; they have enabled an idea to be put forward of the composition of the repeating unit of the O-specific side chains of the lipopolysaccharide.Pacific-Ocean Institute of Bioorganic Chemistry of the Far-Eastern Scientific Center of the Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 563–570, September–October, 1975. 相似文献
752.
A. Yu. Lyapunov T. I. Kirichenko E. Yu. Kulygina N. G. Luk’yanenko 《Russian Journal of Organic Chemistry》2005,41(1):144-150
Alkylation of 2,7-dihydroxy-9H-fluoren-9-one with 2-(2-chloroethoxy)ethanol, 2-[2-(2-chloroethoxy)-ethoxy]ethanol, and 2-{2-[2-(2-chloroethoxy)ethoxy]ethoxy}ethanol in dimethylformamide in the presence of potassium carbonate gave 78–80% of the corresponding diols which were treated with p-toluenesulfonyl chloride in a dioxanechloroform mixture in the presence of triethylamine at 0– 5°C (30 h). The resulting bis(p-toluene-sulfonates) were brought into condensation with 2,7-dihydroxy-9H-fluoren-9-one in a very dilute solution in dimethylformamide containing anhydrous potassium carbonate at 80–85°C. Appropriate treatment of the reaction mixture, followed by chromatographic purification afforded 53–27% of the first representatives of a new class of cyclophanes, bis(oxofluoreno)crownophanes. Raising the temperature to 95–105°C resulted in an appreciable decrease of the product yield. The yield of the target products did not increase on replacement of potassium carbonate by cesium carbonate.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 144–149.Original Russian Text Copyright © 2005 by Lyapunov, Kirichenko, Kulygina, Luk’yanenko. 相似文献
753.
V. M. Granchak A. Yu. Tarasyuk I. I. Dilung 《Theoretical and Experimental Chemistry》1990,26(1):49-55
The photoreduction of benzophenone by dimethylaminoethyl methacrylate was investigated under the conditions of stationary and pulsed irradiation. With stationary irradiation of this system in benzene an intermediate photoproduct is formed, and its destruction is described by a kinetic equation of second order. By irradiation under pulsed conditions it is possible to detect the formation of the ketyl radicals of benzophenone, the yield and destruction of which depend substantially on the nature of the medium. The relationship between the destruction constant and the concentration of the aminomethacrylate and butyl methacrylate was examined and explained; the constant increases with decrease in the aminomethacrylate concentration and with increase in the butyl methacrylate concentration. The mechanism of the photoreduction of aromatic carbonyl compounds by aminomethacrylates is described.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 1, 56–62, January–February, 1990. 相似文献
754.
The electrophoretic and amino acid compositions of the proteins of lines of maize differing in the anthocyan coloration of their seeds have been investigated. The molecular masses of the quantitatively main components ranged from 11 to 42 kDa for the albumins and from 15 to 81 kDa for the globulins. Differences between the lines were observed in the levels of components with molecular masses of from 11 to 31 kDa. The amino acid compositions of the zeins of the lines studied were characterized by high levels of leucine, glutamic acid, aspartic acid, alanine and serine, and those of the other groups of proteins by high levels of arginine, glutamic acid, and glycine.Institute of Genetics, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 64 22 30. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 871–873, November–December, 1997. 相似文献
755.
Summary LC was used for the separation of several cardiac glycosides with water-alcohol eluents on a silanised silica column. The influence of temperature and composition of the eluent on the retention time, the retention volumes of the glycosides, the selectivity and the capacity factor of the column were studied. Higher temperature and a higher ethanol content in the eluent reduce the retention time, the selectivity and the capacity factor but the efficiency of the column increases. The best separation of six glycosides studied was obtained at 50°C, the ethanol content in the eluent being about 30%. 相似文献
756.
L. D. Ashkinadze C. V. Afanas'eva L. A. Sviridova N. E. Mysova A. N. Kashin Yu. G. Bundel' 《Chemistry of Heterocyclic Compounds》1989,25(7):780-783
In solutions, 1-acyl-5-hydroxypyrazolidines form only intermolecular hydrogen bonds in which the proton acceptor is the oxygen atom of the hydroxyl group. These compounds are similar to phenols with respect to the acidity in a hydrogen bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 936–939, July, 1989. 相似文献
757.
A. A. Shachkus R. Yu. Dyagutite Z. A. Stumbryavichyute 《Chemistry of Heterocyclic Compounds》1990,26(5):527-529
Reaction of 2,3,3-trimethyl-and 2,3,3,5-tetramethyl-3H-indole hydrochlorides with methacrylic and crotonic amides gives 3- and 4-methyl-1,2,3,4,10,10a-hexahydropyrimido[1,2-a]indol-2-ones. With perchloric acid these are converted to 1-carbamoylpropyl-3H-indolium perchlorates. The syntheses of 10a-(4-dimethylaminostyryl)- and 10a-[(4-dimethylaminophenyl)butadienyl]-3,10,10-trimethylpyrimido[1,2-a]indol-2-ones have been studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 625–627, May, 1990. 相似文献
758.
Track membrane with immobilized colloid silver particles 总被引:1,自引:0,他引:1
A. Yu. Solov’ev T. S. Potekhina I. A. Chernova B. Ya. Basin 《Russian Journal of Applied Chemistry》2007,80(3):438-442
A method for modification of track membranes by immobilization of polymer complexes of colloid silver nanoparticles on the surface of microfiltration membranes was developed. The antimicrobial properties of track membranes modified with silver nanoparticles were tested on E. coli, Ps. aeruginosa, St. aureus, and B. cereus. 相似文献
759.
Conclusions An x-ray diffraction structural analysis showed that the distortions in the geometries of sterically strained 4,16-dichloro- and 4,16-dibromo[2.2]paracyclophanes are similar to those found in unsubstituted [2.2]paracyclophane. The introduction of bulky halogen atoms at C4 and C16 in the [2.2]paracyclophane molecule does not lead to a marked increase in the steric repulsion of the benzene rings. The polar nature of the halogen atoms leads to dipole-dipole attraction of the antiparallel benzene rings which are drawn somewhat closer to each other and to the halogen atom of the other ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2007–2010, September, 1986. 相似文献
760.
The recyclization of pyrrolo[1,2-a]pyrazinium salts under the influence of a base leads to 8-aminoindolizine derivatives and is a new method for the synthesis of indolizines, as well as the first example of the Kost—Sagitullin rearrangement in the pyrazine series.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 763–766, June, 1991. 相似文献