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1.
The structures of phenolic alkaloids isolated previously fromVinca erecta Rgl. et Schmalh. have been reconsidered on the basis of the results of a study of their13C NMR spectra, and it has been shown that a base with mp 228–229° has the structure of 11-hydroxystrictamine and an amorphous base of the same composition isomeric with it is 10-hydroxystrictamine. The structures of two new indolenine alkaloids — ercinamine and ercinaminine — have been determined from an analysis of13C NMR spectra, and also on the basis of PMR and IR spectra and chemical transformations.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 483–488, July–August, 1983.  相似文献   

2.
A highly purified electrophoreticaly homogeneous protein with a NGF activity of 10·105 BU/mg of protein have been isolated from the venom of the Central Asian cobra by gel-filtration and ion-exchange chromatography followed by preparative isolectric focusing in a thin layer of Sephadex. It has been shown that the NGF isolated is characterized by a molecular weight in the range of 20–30 kD and a pI value of about 7.0.Institute of Biochemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii. No. 4, pp. 546–551, July–August, 1985.  相似文献   

3.
The interaction of the sage, mint, apple, and ginseng pectins, isolated from tissue culture wastes and purified with copper, mercury, zinc, and cadmium salts, has been studied by the amperometric method with two metal indicator electrodes. The optimum conditions of titration have been determined: pH 3.5–5.0; concentration of pectin substances 5·10–5-1·10–3 g/ml of solution. It has been established by graphical and mathematical methods that the interaction is accompanied by the formation of compounds with a ratio of the carboxy groups of pectins to the metal cation of two. The IR spectra of sage pectin and of copper and mercury pectinates are given.M. V. Frunze, Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 171–175, March–April, 1988.  相似文献   

4.
Aucubin and five substances of iridoid nature designated as A, B, C, D, and E have been isolated from two species of plants — Lagotis integrifolia (Willd.) Schisk and Incarvillea olgae (Rgl.). The IR, UV, mass, PMR and13C NMR spectra of substance A have been studied, and an x-ray structural investigation has been made of its tetrahydro derivative. This has shown that substance A is 7-benzoyltecomoside.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 61–69, January–February, 1995. Original article submitted November 1, 1994.  相似文献   

5.
Two monosaccharides have been found by paper chromatography in an aqueous extract of the herbage of red clover (Trifolium pratense). One of them has been identified as glucose. After hydrolysis of a dry water-soluble extract by paper chromatography in the presence of markers, galactose, arabinose, xylose, and mannose were detected. By paper chromatography in the presence of markers the amino acids phenylalanine, leucine (isoleucine), methionine, aspartic acid, proline, alanine, and histidine have been identified. Phytin with decomp. p 276°C has been isolated and identified, giving, after hydrolysis, inositol with mp 225–226°C, and Ca2+, Mg2+, and PO 4 3– have been detected. The amount of ash in the herbage of clover is 8.4% and the amount insoluble in HC1 1.5%. The amounts of macroelements were determined by the flame photometry of a solution of the ash (mg–%): K+ 1620; Na+ 310; Ca2+ 1240; Mg2+ 1090.Pyatigorsk Pharmaceutical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 483–485, July–August, 1980.  相似文献   

6.
Summary Di-2-ethylhexyl phthalate has been isolated from the neutral lipids fraction of the culture liquid of the fungusVerticillium dahliae Kleb. Its1H and13C magnetic resonance spectra have been obtained, and an assignment of the signals has been made.On the basis of their UV, IR, and ESR spectra, the chromogenic components of the neutral lipid fractions have been assigned to the melanins.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 689–693, November–December, 1975.  相似文献   

7.
The known cembrenolide sarcophin and its new acetoxy derivative — 13-acetoxy-7,8-epoxycembra-1(15),3,11-trien-2,16-olide — have been isolated from the soft coralLobophytum sp.. The compounds isolated are inhibitors of the activity of Na+K+-ATPase and are membranotropic agents. The structures of the compounds have been shown on the basis of the results of NMR spectroscopy.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 762–765, November–December, 1990.  相似文献   

8.
A new base — sophorine, with mp 59–60°C, [] D 23 -18.9° (c 0.98; ethanol) — has been isolated from the epigeal part of the plantSophora alopecuroides L. Its IR spectrum and the nature of its mass spectrometric composition have permitted sophorine to be assigned to the quinolizidine alkaloids. The13C NMR spectrum has shown the presence of 19 carbon atoms. The analysis of several of the carbon signals has confirmed the results of IR and mass spectroscopy. Additional details of the structure of sophorine have been obtained from its PMR spectrum.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 604–608, September–October, 1981.  相似文献   

9.
A Ca2+-dependent protein kinase C, active at pH 6.5–8.0 has been found in cotton seeds for the first time. The localization of the enzyme in the seeds has been established and some of its properties are described (stability in various media, capacity for performing the phosphorylation of various substrates, activation by calcium ions). Highly active preparations of cottonseed protein kinase C have been isolated by biospecific chromatography.Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 255–259, March–April, 1989.  相似文献   

10.
The structure of the alkaloid isoregecoline (I) with the composition C19H23O4N+, mp. 284–286°C, isolated previously fromColchicum kesselringii Regel growing in the flood plains of the R. Chirchik has been established. It has been shown by IR, PMR and mass spectroscopy and chemical transformations that (I) is an epimer of regecoline isolated from a plant of the same species.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 808–810, November–December, 1985.  相似文献   

11.
The reduction of CrO3 with an excess of L-ascorbic acid and its interaction with DNA fragments (adenine, adenosine) and the ATP nucleotide was studied by the analysis of the isolated solid products. The precipitates were characterised by elemental analyses, FAB-mass spectral data, spectroscopic methods (u.v.–vis., i.r) and magnetic measurements. The CrIII complexes obtained from ternary systems appeared to be [CrIIIL-ascorbic acid] and [CrIIIL-ascorbic acid–adenine (adenosine, ATP)] species. The structure of ternary complexes has been proposed assuming hydrogen bond formation between the [CrIII–ascorbic acid] complex and the DNA components. The effect of main cellular reductants: cysteine, glutathione and L-ascorbic acid on the composition and structure of isolated products has been discussed.  相似文献   

12.
In the work model calculations of the vibrations of ideally isolated silicooxygen rings (using PM3 method) have been carried out. three-, four-, and six-membered rings have been considered. It has been found that that the three-membered silicooxygen rings are flat and practically undeformed showing D3h symmetry. The rings of higher number of ring members (i.e. n>3) are deformed to some extent. The deformation reveals itself most significantly in the Si–O–Si bond angles distribution. In the case of all the rings the bridging Si–O–Si bonds are ca. 0.02–0.04 Å shorter than the non-bridging Si–O bonds. Hypothetical IR spectra for all the rings considered have been also calculated. Analysis of these hypothetical spectra leads to the conclusion that the whole spectrum can be divided into four wavenumbers regions, 1200–1100 cm−1 stretching Si–O(Si) vibrations; 1000–800 cm−1 stretching Si–O vibrations; 800–600 cm−1; the region in which a band characteristic of silicooxygen rings appears, and below 600 cm−1 bending O–Si–O and (Si)O–Si–O(Si). It has been also found that as the number of ring members increases the ‘ring band’ shifts to lower wavenumbers: 725 cm−1 for three-membered rings, 650 cm−1 for four-membered rings and 610 cm−1 for six-membered rings. Calculated spectra have been compared with the experimental spectra of cyclosilicates. They showed good agreement in the 1200–600 cm−1 region. In the experimental spectra as well as in the calculated ones, with increasing the number of ring members the ‘ring band’ shifts towards lower wavenumbers.  相似文献   

13.
Summary From the epigeal part ofStizolophus balsamita (Lam.) Cass. ex Takht. a new sesquiterpene lactone balsamin has been isolated with the composition C20H26O6, mp 242–244°C (from ethanol), [] D 17 –45.70° (c 1.9; chloroform). Do the basis of the basis of the IR, UV, and PMR spectra of balsamin and its acetate, a stereochemical structure has been proposed for balsamin, and the structures of stizolin and stizolicin isolated previously from the same plant have also been supplemented by stereochemistry.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 467–472, July–August, 1976.  相似文献   

14.
Squalene, 35-methoxyho-6-ene-32R,33R,34S-triol, hop-22(29)-ene, and hopan-22-ol have been isolated fromAcetobacter sp. VSB 917. The structures of the substances isolated and of the 35-methoxyhop-6-ene-32R,33R,34S-triol triacetate obtained have been established by IR, mass, and1H and13C NMR spectroscopies.Vitaminy Scientific-Production Association, Moscow. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 367–372, May–August, 1992.  相似文献   

15.
Díaz TG  Cabanillas AG  Soto MD  Ortiz JM 《Talanta》2008,76(4):809-814
Square-wave adsorptive-stripping voltammetry technique has been used to develop a method for the determination of fenthion in olive oil. Due to the fact that fenthion does not give any electrochemical signal at mercury electrode, the method has been based on a previous oxidation of fenthion to its metabolite, fenthion-sulfoxide, by using KMnO4. The metabolite gives rise to a peak due to an adsorptive-reductive process at −0.786 V. Fenthion is isolated from olive oil by carrying out a solid–liquid extraction procedure using silica cartridge, followed by a liquid–liquid partitioning with acetonitrile. The detection limit in olive oil is 78.8 ng g−1 and recoveries for four levels of fortification are ranged from 85% to 109%. On the other hand, it has been developed a method for the simultaneous determination of fenthion and its metabolite fenthion-sulfoxide, in river water. Pesticides are isolated from water by carrying out a liquid–liquid partitioning with trichloromethane. The detection limits are 0.41 ng g−1 and 0.44 ng g−1, for fenthion and fenthion-sulfoxide, respectively. Recoveries for three levels of fortification are ranged from 96% to 103% for fenthion and 94% to 104% for fenthion-sulfoxide.  相似文献   

16.
Summary Reaction between K2[ReI6] and KSCN in boiling MeOH or in the melt gave [Re(NCS)6]2– and a weakly paramagnetic species, isolated as its Cs salt. Tl, Me4N and other salts of this species have been isolated from the reaction medium of from the Cs salt by metathesis. On the basis of magnetic susceptibility and i.r. spectra the new complex has been formulated as [Re2(NCS)12]4– containing metalmetal bond and no bridging thiocyanate. The Me4N salt has also been isolated by bioling aqueous solutions of HReO4 and HSCN and then adding Me4NCL. A pyridinium salt, formulated as (pyH)4[Re2(NCS)12], has been obtained by boiling [ReO2py4]NCS with aqueous HSCN. The two complex species [Re(NCS)6]2– and [Re2(NCS)12]4– show distinctly different magnetic moment and electronic spectra.  相似文献   

17.
Stachybotrys alternans produces a series of low-molecular-mass compounds. By their column chromatography we have isolated the nitrogen-containing compound stachybotrin. The structure of stachybotrin has been determined on the basis of chemical transformations together with the results of1H and13C NMR spectroscopy, 2M NMR1H–1H and1H–13C chemical shift correlation (COSY), correlation of long-range1H–13C interactions (HMBC), measurements of NOEs in a rotating coordinate system (ROESY), and IR and electronimpact mass spectra.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 599–607, July–August, 1997.  相似文献   

18.
Twenty-five pure environmentally relevant toxaphene components have been isolated from photochemically modified technical toxaphene by means of a combination of column chromatography on silica gel and preparative high resolution liquid chromatography. These compounds are 6 chlorinated camphenes (1–3, 5, 7, and 11) and 19 chlorinated bornanes (4, 6, 8–10, 12–16, 18–24, 26, and 27 according to Table 1). Two further chlorobornanes (17 and 25) have been isolated from a highly chlorinated mixture obtained by the excess chlorination of 2-exo,10-dichlorobornane. The structural elucidation of the isolated compounds has been carried out with spectroscopical methods.  相似文献   

19.
Four new heteronuclear CrIII/VIV complexes have been isolated from the redox [CrIII–Vv–L1–L2] systems (L1 = glycine, glutaminic and nicotinic acids, L2 = cysteine and glutathione). The complexes have been analysed by spectroscopic methods (diffuse reflectance u.v./vis., i.r.) and by FAB mass spectra. A significant bathochromic shift of the d–d CrIII and VIV transitions in heteronuclear complexes (d1–d3) in comparison to the CrIII homonuclear species (d3/d3) has been related to the interaction of two metal centres. Spectral analyses by the digital filter and band deconvolution methods are presented.  相似文献   

20.
Two new 7-hydroxycoumarins have been isolated from the roots ofFerula lehmannii (Lehmann's giant fennel): lehmferidin (I), C24H28O4, M+ 380, mp 173–174°C, and lehmferin (II), C24H30O4, M+ 382, mp 118–119°C; and badrakemin (III) has also been identified. The structures and configurations of the asymmetric centers of the new coumarins have been established on the basis of spectral characteristics and conversion into known substances.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 709–712, November–December, 1983.  相似文献   

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