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31.
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   
32.
The structure and stereochemistry of crotocaudin, a new norditerpene occurring as a minor constituent in Crotoncaudatus Geisel (Euphorbiaceae) have been established as ent-8S,10S-15,16-epoxy-19-norcleroda-4,11,13(16), 14-tetraene 18,6S: 20,12-diolactone 7 from the detailed studies of 1H NMR spectra using lanthanide shift reagents, decoupling experiments and chemical reactions. The congener, teucvidin, ent-10S-15,16-epoxy-19-norcleroda-4,13(16), 14-triene-18,6S: 20,12R-diolactone 1 was obtained as a major component besides several triterpenoids viz taraxerone 2, taraxerol 3 and taraxeryl acetate 4. 13C NMR and 1H NMR spectra and a few novel reactions of teucvidin and its conversion to teucvin, ent-(6R,12R)-15,16-epoxy-19-nor-9,4-friedolabda-4,13(16),14-triene-18,6:20, 12-diolactone 6 are also reported.  相似文献   
33.
A quaternary salt of 4-(diethylamino)butan-2-one, methyldiethyl-3-ketobutylammonium methyl sulfate, is used as an alkylating agent to synthesize lepidine and 1-phenyllepidine salts. The method gives good yields, under mild conditions, of lepidine and 1-phenyllepidine perchlorate. An intermediate product is isolated, and a reaction mechanism suggested.  相似文献   
34.
The investigation of the boundary-value problem on a half-plane for the two-dimensional stationary Heisenberg magnet is continued. The asymptotic behavior of N-soliton solutions is discussed. The asymptotic contribution of the continuous spectrum is calculated. The gauge equivalence of the boundary-value problems for the models of a magnet and the elliptic equation represented by the sinh—Gordon equation is considered.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 104, No. 3, pp. 513–529, September, 1995.  相似文献   
35.
This paper is devoted to the measurement of low-degree p mode rotational splitting, which is one of the most urgent problems in helioseismology. The last three years witnessed considerable progress in this field. It can be stated with confidence that the angular velocity of solar core rotation exceeds only marginally or even does not exceed the rotation velocity of the Sun envelope, except for an area of radius 0.1R in the deep interior of the core. Further progress in this avenue encounters a variety of serious difficulties for lack of reliable data on g modes. These difficulties are due to the physical nature of the p modes themselves and the imperfection of the analytical techniques.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 10, pp. 1218–1221, October, 1996.  相似文献   
36.
The crystal structure of C6H16N8O2·CuCl2, a biguanide metal complex, has been determined by X-ray diffraction data using MoK radiation. The compound crystallizes in the monoclinic space groupP21/a, witha=11.074(4),b=12.061(4),c=5.312(3)Å and=102.8(1)°.The structure was solved by direct methods and refined by full-matrix least-squares to a finalR value 0.037 with 1245 unique reflections. The complex molecule is centrosymmetric, with the Cu atom (0.5,0.5,0.5) on a crystallographic center of symmetry. The complex molecule is rhombic planar with a trans configuration.  相似文献   
37.
Information is given on vegetable tanning substances, their classification, distribution in the plant world, and structure, and the dependence of their tanning properties on their composition, and also on methods of enriching tanning extracts. The review of literature sources includes publications from 1950 to 1989.A. S. Sadykov Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 293–307, May–June, 1990.  相似文献   
38.
Generation of the second- and fourth-order harmonics of laser radiation is reported in Mg vapor at the forbidden 3s 21 S o–4s 1 S o transition. The conversion efficiency for the second-order harmonics has been measured to be 10–2% and for the fourth one 10–8%.  相似文献   
39.
The Ca2+-phospholipid-dependent protein kinase from cottonplant shoots was purified by chromatography on DEAE-Sepharose CL-6B, and then on phenyl-Sepharose CL-4B. According to electrophoresis in PAAG, the enzyme was practically homogeneous and had a molecular mass of 57 kDa. In the presence of Ca2+ alone, the enzyme was activated to only a slight degree. Under the combined action of Ca2+ and a phospholipid the action of the enzyme rose severalfold. A determination of amino acid specificity showed that the protein kinase isolated was a serine- and threonine-specific protein kinase.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 100–105, January–February, 1994.  相似文献   
40.
Reactions of ethyl and tert-butyl phosphorodiamidites with chloroacetone, bromoacetone, and -chloroethyl acetate were studied. The reaction pathway is determined by the structure of the intermediate quasiphosphonium compound responsible for the formation of the Arbuzov product as well as for the occurrence of the amonalous reaction yielding vinyl phosphate.  相似文献   
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