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1.
Literature information on the HPLC of alkaloids, including adsorption, reversed-phase, ion-exchange, ion-pair, and other variants is generalized. Results are given of the chromatographic analysis of various classes of alkaloids with an indication of the conditions of separation, and the columns used, and also of the methods of detection. The advantages and disadvantages of the HPLC variants are discussed. The review includes the literature over the last 14 years. Scientific Center for Chromatography, Institute of Chemistry and Physics of Polymers, Uzbek Academy of Sciences, Tashkent. Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 595–613, September–October, 1991.  相似文献   

2.
Institute of Inorganic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Institute of Catalysis, Siberian Branch, Academy of Sciences of the USSR. Institute of Chemistry and Chemical Technology, Siberian Branch, Academy of Sciences of the USSR. Branch of the Institute of Chemical Physics, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 29, No. 6, pp. 90–103, November–December, 1988.  相似文献   

3.
Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Institute of Physiology and Biophysics, Academy of Sciences of the Republic of Uzbekistan, 700095, Tashkent, ul. Niyazova, 1. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 625–627, July–August, 1995. Original article submitted November 9, 1994.  相似文献   

4.
The compositions of cottonseed soapstocks from first-grade and low-grade cotton seeds have been studied by the methods of CC on polyamide and on silica gel, TLC, GLC, ESR, and UV, IR, and mass spectrometry. It has been found that saturated, and also oxygenated, fatty acids, nonpolar acylglycerols, glycolipids, sterols, arylalkanes, gossypol pigments, and ions of metals of variable valence are concentrated in the acid fat of the soapstock from low-grade seeds. The soapstock contains a very small amount of tocopherols and phospholipids, mainly phosphatidylinositols. The combined gossypol pigments of the soapstocks include stabilized gossypol radical ions.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 502–508, July–August, 1988.  相似文献   

5.
We apply differential scanning calorimetry (DSC) to measure the kinetics of the βδ solid-solid phase transition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, HMX. Integration of the DSC signal gives a direct measurement of degree of conversion. Data is analyzed by first-order kinetics, the Ozawa method, and isoconversional analysis. The range of activation energies found in this work, centering around 500 kJ/mol, is much higher than previously reported values by Brill and co-workers [AIAA J. (1982)], 204 kJ/mol [1], and Henson et al. and Henson and co-workers [B. Henson, L. Smilowitz, B. Asay, P. Dickson, Thermodynamics of the beta to delta phase transition in PBX-9501, in: Proceedings of American Physical Society Topical Group on Shock Compression of Condensed Matter, American Institute of Physics, Atlanta, GA, 2001; L. Smilowitz, B. Henson, J. Robinson, P. Dickson, B. Asay, Kinetics of the beta to delta phase transition in PBX-9501, in: Proceedings of American Physical Society Topical Group on Shock Compression of Condensed Matter, American Institute of Physics, Atlanta, GA, 2001; P.M. Dickson, B.W. Asay, B.F. Henson, C.S. Fugard, J. Wong, Measurement of phase change and thermal decomposition kinetics during cookoff of PBX-9501, in: Proceedings of American Physical Society Topical Group on Shock Compression of Condensed Matter, American Institute of Physics, Snowbird, UT, 1999], 200 kJ/mol [4]. We discuss possible reasons for the higher activation energies measured here but do not identify the cause.  相似文献   

6.
The present review gives the main advances made in the laboratory of alkaloid chemistry of the Institute of Plant Substances of the Usbekistan Republic Academy of Sciences [IKhRV AN RUz] (Tashkent) over 50 years in the field of the chemistry of diterpene, isoquinoline, quinoline, steroid, indole, spiropiperidine, sulfur-containing, tropane, pyrrolidine, quinazoline, quinolizidine, amaryllis, and pyrrolizidine bases and possible routes for the biosynthesis of some of these groups of alkaloids.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–33, January–February, 1993.  相似文献   

7.
High-performance liquid chromatography of alkaloids   总被引:2,自引:0,他引:2  
Literature information on the HPLC of alkaloids, including adsorption, reversed-phase, ion-exchange, ion-pair, and other variants is generalized. Results are given of the chromatographic analysis of various classes of alkaloids with an indication of the conditions of separation, and the columns used, and also of the methods of detection. The advantages and disadvantages of the HPLC variants are discussed. The review includes the literature over the last 14 years.Scientific Center for Chromatography, Institute of Chemistry and Physics of Polymers, Uzbek Academy of Sciences, Tashkent. Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 595–613, September–October, 1991.  相似文献   

8.
In our study, we aimed to synthesize novel, some biologically active compounds, Azoles and Azines derivatives, that to be nitrogen-containing heterocycles, and have their diverse therapeutic values. Thiosemicarbazide, 2 , was obtained from the attack of nitrogen of hydrazine to the carbon of heteroallene function of compound 1. Triazolotriazole derivative, 4 , was obtained from the reaction of 2 with diethyl malonate. Cyclization of thiourea unit of compound 2 with heteroallene, 1 , gave trazine, 6 . Benzolyation of 2 using benzoyl chloride formed triazole derivative, 8 . Reaction of 2 and maleic anhydride gave furothiadazine, 10. Cyclohexanopyrimidinthione, 12 , was obtained from cyclocondensation of cyclohexanone with 2. Triazole, 14 , was obtained from 2 and ammonium isothiocynate under thermal condition. Reaction of 2 with ethyl bromoacetate gave thiazole derivative, 16. [2+3] Cyclocondensation of acetyl acetone with 2 provided pyrazole, 18 . Triazolotriazole, 20 , was obtained from formalin and 2. Compound 2 suffers intramolecular base mediated cyclization affording pyrazole, 21. Keeping 2 and propinaldehyde under reflux provided triazolotriazole, 24. Acylation of 2 by succinic acid formed pyridazine derivative, 27.  相似文献   

9.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Institute of Physics, Siberian Branch, Russian Academy of Sciences. Buryat Institute of Natural Sciences, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 3, pp. 126–130, May–June, 1992.  相似文献   

10.
Institute of Inorganic Chemistry, Academy of Sciences of the USSR, Siberian Branch. Institute of Organic Chemistry, Academy of Sciences of the USSR, Siberian Branch. Translated from Zhurnal Strukturnoi Khimii, Vol. 28, No. 5, pp. 73–80, September–October, 1987.  相似文献   

11.
Conclusions 1. The chemical composition of mixtures of resin acids isolated from the balsams of native conifer species, Scotch, Crimean, and Siberian pines andP. hamota andP. pityusa, Norway spruce, and Siberian larch, has been studied by the GLC method.2. The following resin acids are present in the balsams: pimaric, sandaracopimaric, levopimaric, palustric, isopimaric, abietic, dehydro- and dihydroabietic, neoabietic, four acids of undetermined chemical structure, and fatty acids. The balsams differ in the quantitative composition of the resin acids that they contain.Institute of Physical Organic Chemistry, Academy of Sciences of the Belorussian SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 539–541, September–October, 1970.  相似文献   

12.
The alkaloid compositions of the roots, young shoots, and leaves of Berberis sibirica have been studied, and berberine, palmatine, columbamine, berberrubine, oxyacanthine, berbamine, 8-oxoberberine, 8-oxoberrberubine, pakistanine, and pronunciferine, and also the new base N-acetylhomoveratrylamine have been isolated. This is the first time that any of these alkaloids, except berberine, have been isolated from this plant.Andizhan State Medical Institute. Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 424–428, May–June, 1993.  相似文献   

13.
为探讨小儿脑性瘫痪(CP)体内微量元素的变化,测定了128例脑性瘫痪患者血钙、锌、铁、铜、镁含量,随机选择128例正常儿童进行对照分析。结果表明,两组病例血锌、铜、镁均在正常范围,脑瘫组血钙56例、铁45例低于正常参考值,健康组血钙16例、铁11例低于正常参考值。经统计学处理,两组病例中血钙、铁、铜、镁含量具有显著性差异(P<0.05),血锌无显著性差异(P>0.05)。提示脑瘫儿童血钙、铁、铜、镁含量均低于正常儿童,补充钙、铁、镁等可能有利于脑瘫康复。  相似文献   

14.
The methyl esters of colchicidylglycyl-L-leucine, -L-phenylalanine, and-L-tryptophan and the ethyl esters of colchicidylglycylglycine, -L-isoleucine,-L-valine, -L-tyrosine, and -L-glutamic acid have been obtained by the condensation of colchicidylglycine and esters of amino acids. The structures of the compounds have been confirmed on the basis of their UV spectra and nuclear magnetic resonance spectra.Institute of Molecular Biology and Biochemistry, Kazakh SSR Academy of Sciences, Alma-Ata. Institute of Molecular Biology, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 91–95, January–February, 1989.  相似文献   

15.
    
In the course of a further study of the alkaloids of the epigeal part of Aconitum turczaninowiia new alkaloid has been isolated, which has been named turpelline. A structure for turpelline has been proposed on the basis of a study of its IR, mass, PMR, 13 C NMR, and 2D COSY spectra.Institute of Chemistry, Mongolian Academy of Sciences, Ulan-Bator. Irkutsk Institute of Organic Chemistry, Siberian Division of the Russian Academy of Sciences. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 740–743, September–October, 1993.  相似文献   

16.
This review gives information on the distribution of flavonoids (flavonol and anthocyanin glycosides, catechins, and proanthocyanidins in plants of the family Malvaceae, namely the various species of the genera Gossypium, Hibiscus, Altheae, etc. It is shown that the flavonols are represented by glycosides of kaempferol, quercetin, myricetin, herbacetin. gossypetin, and hibiscetin, the most widespread being glycosides of quercetin and kaempferol. Characteristic for the majority of representatives of the families that were studied are flavonols having a hydroxy group in the C-8 position. Anthocyanins are represented by glycosides of cyanidin and of delphinidin. However, together with these, glycosides of methoxylated anthocyanins have also been detected — peonidin, petinidin, and malvidin. Sources of a food dye have been revealed among representatives of the family. Literature sources up to 1991 have been included.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. 3–19, January–February, 1994.  相似文献   

17.
The acid-base properties and chemical composition of the surface of solid solutions and binary components of the InSb-ZnTe system were studied by the hydrolytic adsorption, nonaqueous conductometric titration, mechanochemistry, IR spectroscopy, and mass spectrometry methods. The strength, nature, and concentration of acid centers were determined. Changes in the concentration of acid centers caused by surface exposure to CO and changes in the composition of the system were also studied. The mechanism of acid-base interactions was established. The chemical composition of the surface of system components exposed to air included adsorbed H2O molecules, OH groups, hydrocarbon and oxocarbon compounds, and the products of surface atom oxidation. After thermal treatment in a vacuum, the composition of the surface approached the stoichiometric composition. Original Russian Text ? I.A. Kirovskaya, E.G. Shubenkova, O.T. Timoshenko, T.N. Filatova, 2008, published in Zhurnal Fizicheskoi Khimii, 2008, Vol. 82, No. 4, pp. 732–738.  相似文献   

18.
19.
Institute of Inorganic Chemistry, Academy of Sciences of the USSR, Siberian Branch. Institute of Geology and Geophysics, Academy of Sciences of the USSR, Siberian Branch. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 1, pp. 67–73, January–February, 1990.  相似文献   

20.
It has been established that, in contrast to the pure substances, the thermal decomposition of hexacyanotransition metal complexes, encapsulated in the large cavities of faujasite, occurs by a hydrolytic mechanism. The composition of the gaseous products of the thermal decomposition depend on the characteristics of the localization of the cations in the inclusion compounds. L. V. Pisarzhevskii Institute of Physical Chemistry, National Academy of Sciences of Ukraine, 31 Prospekt Nauki, Kiev 252039, Ukraine. Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 35, No. 2, pp. 107–112, March–April, 1999.  相似文献   

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