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1.
    
The isomerization of 5-vinyl-2-norbornene (1) has been studied in the presence of Co (R1-COCHCOR2)x–Et6–yAl2Cly (x=2, 3; y=2–4) catalytic systems. Co(acac)2–AlEt3 and Co(acac)3–AlEt3 systems isomerize1 to 5-ethylidene-2-norbornene (2), whereas the Co(PhCOCHCOPh)2–AlEt3 system selectively forms 3-vinylnortricyclene (3).2 is always accompanied by formation of ethylidene norbornane (4). A possible mechanism for formation of products is proposed.  相似文献   

2.
The composition of the fatty mono- and dihydroxy acids of the fruit ofRumex paulsenianus Rech. fil. (familyPolygonaceae) has been determined by a combination of IRS, UVS, GLC, and mass-spectrometric methods. (22) Monohydroxy acids of the C14–C20 series, including isomers and isologues, and four dihydroxy acids from C18 to C20, including a new isomeric 9-OH-10, 12–17:2 acid have been detected.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 762–765, November–December, 1991.  相似文献   

3.
Summary 1. Pectic acid contains galacturonic acid (78–83%) and, chemically linked with it, the monosaccharides D-galactose, L-arabinose, L-rhamnose, and substance (VIII) and (IX).2. By fractionating the polysaccharide complex of the leavesof Plantago major L. on a DEAE-cellulose column it has been shown that it consists of pectic acid (80–82%), and free galactoraban (5–6%) and galactan (4–5%).Khimiya Prirodnykh Soedinenii, Vol. 1, No. 6, pp. 369–372, 1965.We have used Kertesz's nomenclature of pectic compounds [4].  相似文献   

4.
Summary From the culture liquid of the mutant strains 47 and 48 ofAct. olivovariabilis a new o-naphthoquinone — olivovarin — has been isolated. Structure (I) is proposed for it.All-Union Scientific-Research Institute of Antibiotics. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 339–344, May–June, 1975.  相似文献   

5.
The possibility has been shown of obtaining NGFs in the process of isolating coagulant proteinases and other biologically active substances from the venoms of theAgkistrodon halys halys and theEchis multisquamata. Results characterizing the NGFs of both species as basic (weakly basic) proteins with molecular masses of 30.0–40.0 kDa are presented.Institute of Biochemistry, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 266–270, March-April, 1992.  相似文献   

6.
Summary Structure (I) is proposed for arnifolin — a sesquiterpene lactone fromArnica foliosa Nutt. andArnica montana L.All-Union Scientific-Research Institute for Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 270–272, May–June, 1971.  相似文献   

7.
Summary A spectrophotometric method is proposed for determining the content of aspidin in a crystalline powder and in the rhizomes of the fernsDryopteris spinulosa (M),D. phegopteris (L.), andD. fragrans (L.) Schott.All-Union Scientific-Research Institute for Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 684–687, November–December, 1970.  相似文献   

8.
Conclusions A new sesquiterpene lactone, saupirin, has been isolated from the epigeal green part ofSaussurea neopulchella Lipsch. andSaussurea pulchella Fisch., and structure (I) has been proposed for it.All-Union Scientific-Research Institute for Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 727–736, November–December, 1971.  相似文献   

9.
We have studied the uptake of237Np in marine plants and animals belonging to several phyla, and collected samples from the end of January 1986 to March 1986, in a sampling station situated near the outlet of the irradiated fuel reprocessing plant at La Hague.We determined the237Np by neutron activation analysis. This method is very sensitive, with a limit of detection of 5×10–10 mg, 1.3×10–2 mBq. The method consists of the following steps:Reduction of the neptunium to the tetravalent state by treatment with a mixture of hydrazine sulfate and ferrous iron-chromatographic separations on Dowex 1×10 resin in a nitric medium, then in a hydrochloric medium-neutron irradiation in a nuclear reactor-purification of the neptunium by chromatography on Dowex 1×10 resin in a nitric then hydrochloric medium-measurement of the isotope238Np by gamma ray spectrometry using a Ge(Li) detector. The species were collected at Goury, at the northwest extremity of the Cotentin Peninsula, 5 km from the outlet of the reprocessing plant at La Hague. The levels of237Np were as follows: red algaeCorallina officinalis 64 mBq kg–1 wet weight; andChondrus crispus 18 mBq kg–1 wet weight; the spongeHalichondria panicea 14 mBq kg–1 wet weight; the ascidianDendrodoa grossularia 12 mBq kg–1 wet weight. The bivaive molluscsPatella vulgata andGibbula umbilicalis (the flesh ofP. vulgata andG. umbilicalis: 4 and 7 mBq kg–1 wet weight respectively) also prove to be interesting biological indicatorsThe transfer modes of237Np to the various species as a function of their trophic levels are discussed as well as the distribution among the organs in the species consumed and the radiological impact of human consumption.  相似文献   

10.
A hexane extract of the soft coralSarcophyton trocheliophorum has yielded two new diterpenoids for which the structures of 13S-hydroxy-(–)-neocembrene and 13S-hydroxy-11,12-epoxy-(–)-neocembrene have been established.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 535–540, July–August, 1988.  相似文献   

11.
Summary By separating the total alkaloids ofV.erecta according to their basicities in an APS, in addition to bases known previously we have isolated ervincidine, apovincamine, (+)-quebrachamine, dl-eburnamine, (–)-1,2-dehydroaspidospermidine, and kopsanone. This is the first time that these alkaloids have been obtained from this plant. Thin-layer chromatography showed the presence of another 10–12 uncharacterized alkaloids.The region of the passage into the buffer solutions of some alkaloids has also been established.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 713–717, November–December, 1970.  相似文献   

12.
The isolation from the plantDipthychocarpus strictus (Cruciferae) of the optically active base diptaline, identified as N-(11-methylsulfinylundecyl)urea, has been reported [1]. A synthesis of the racemic form of this alkaloid has now been achieved.Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 102–105, January–February, 1992.  相似文献   

13.
Summary The fatty oils of the seeds of the wild speciesZiziphora pedicellata andEremostachys molluceloides (Labiatae) have been investigated. The glyceride, pigment, and hydrocarbon compositions of these oils and the fatty-acid composition of the oil ofZ. pedicellata have been determined.The oil ofE. molluceloides contains laballenic acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 324–328, May–June, 1975.  相似文献   

14.
Summary 1. The content of total alkaloids in the hypogeal parts ofAndrachne rotundifolia C. A. Mey. (family Euphorbicease) is 0.2–0.3% and in the epigeal parts 0.06–0.08%.The total alkaloids in both the hypogeal and the epigeal parts ofAndrachne rotundifolia consist of five or six non-phenolic bases.2. Three individual substances have been isolated: andrachnine C11H17NO2, which is a new alkaloid; base (II), giving a perchlorate with mp 139°–140° C; and base (III) with mp 135°–136° C.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 257–260, 1966  相似文献   

15.
On the basis of a modified Knoevenagel reaction starting from octanol and decanal, the stereodirected synthesis has been effected of dodec-5E-en-ol (the pheromone of the grass flyTricimba cincta — and tetradec-5E-en-yl acetate) an imitator of the pheromone of the mothRhynchopacha sp. A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 129–132, January–February, 1991.  相似文献   

16.
The class compositions of the lipids of leaf vegetables —Spinacea oleracea (variety Ispolinskii),Latuca sativa (variety Kucheryavets Odesskii), andRumex acetosa (variety Odesskii-17) have been studied. The compositions of their NLs (17 groups of individual compounds were identified), GLs (nine groups of compounds were found), and PhLs (seven groups of compounds have been found) have been determined by physicochemical methods of analysis. The maximum amount of the total lipids and also of the PhLs was possessed by the spinach. Among the FAs of the leaf vegetables, USFAs predominated.M. V. Lomonosov Technological Institute of the Food Industry, Odessa. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 199–205, March–April, 1993.  相似文献   

17.
(E)-Dodec-3-en-l-yl acetate — the main component of the sex pheromones ofScrobipalpa ocellatella andScrobipalpopsis solanivora — has been obtained by a three-stage synthesis from decanal and malonic acid. The overall yield of pheromone was 33% calculated on the initial aldehyde.A. S. Sadykov Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 682–683, September–October, 1988.  相似文献   

18.
It has been established by electrophoresis in polyacrylamide gel that the protein component of the lipopolysaccharide-protein complex ofYersinia pseudotuberculosis consists of two poly-peptides with molecular weights of 42,000–45,000 and 18,000–20,000. These polypeptides have been detected in the cell wall ofY. pseudotuberculosis as the main components. Protein fractions B-2 and B-3, differing with respect to solubility in phenol, were isolated from the LPPC ofY. pseudotuberculosis by extraction with hot 45% phenol. These protein fractions had the same polypeptide composition, which is characteristic for membrane proteins. B-3 included the LPS component and B-2 contained lipid A or fragments of it as impurity. Fractions B-3 and B-2 precipitated with antiserum to the LPPC.Pacific Ocean Institute of Bioorganic Chemistry of the Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 92–97, January–February, 1980.  相似文献   

19.
29Si NMR peaks due to species with the double four-membered ring siloxane backbone composed of both Si(O)4/2 and CH3Si(O)3/2 units, (CH3) n Si8O 20 – n /(8 – n) – (n=1–3), formed by co-hydrolysis of tetraethoxysilane and methyltriethoxysilane in the presence of tetramethylammonium ions in methanol have been assigned. It has been found that 29Si NMR peaks due to Si(OSi)3(O) units shift to lower frequencies by replacement of the adjacent Si(O)4/2 units by CH3Si(O)3/2 units, in other words, with increasing m value in Si[OSi(O)3]3 – m [OSi(CH3) (O)2] m (O) (m=0–2). Peaks from CH3 Si(OSi)3 units in the species have also appeared as separated due to the kind of neighbor structural units. On the basis of the assignments, positions of CH3Si(O)3/2 units in the cubic octameric siloxane framework of (CH3) n Si8O 20 – n /(8 – n) – (n=2, 3), for both of which three isomers are present, have been estimated.  相似文献   

20.
Summary The physicochemical properties of the oils of the seeds of seven plants of the family Cruciferae —Cakile maritima, Sisymbrium altissimum, Sisymbrium Loeselii, Descurainia Sophia, Erysimum cheiranthoides, Brassica amoracioides andCrambe pontica — have been studied and their fatty acid compositions have been determined. The results obtained showed no marked differences from those given in the literature.Zaporozhe Medical Institute. Ukrainian Scientific-Research Institute of the Oils and Fats Industry. Zaporozhe Oils and Fats Combine. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 15–18, January–February, 1973.  相似文献   

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