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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.
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   

3.
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   

4.
    
Summary From the hydrocarbon fractions of the oleoresins ofPicea obovata Ledb andPinus koraensis Sieb. Zucc. a new monocyclic diterpene hydrocarbon — neocembrene — has been isolated, and a structure has been proposed for it.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 694–698, November–December, 1970.  相似文献   

5.
    
A new alkaloid — leuconine — has been isolated from the epigeal parts ofAconitum leucostomum andA. septentrionale, and its structure has been established on the basis of spectral characteristics.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 538–540, September–October, 1992.  相似文献   

6.
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   

7.
Summary One of the possible methods of comparative calculation was used for calculating interatomic distancesd in gaseous alkali halides. The average deviation of the calculated values ofd from experimental values was 0.0012 A (for 15 substances).Translated from Zhurnal Strukturnoi Khimii, Vol. 1, No. 4, pp. 399–403, November–December, 1960  相似文献   

8.
Reserpine, ajmaline, serpentine, ajmalicine, isoreserpiline, and other alkaloids have been isolated from the roots ofRauwolfia cambodiana Pierre ex Pitard,R. verticillata Baill. andR. serpentina Benth.R. vomitoria Afz. was the richest in alkaloids.Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 813–816, November–December, 1991.  相似文献   

9.
The alkaloid compositions of four species of plants of the genusArgemone (A. mexicana L.,A. alba L.,A. platyceras Link et Otto., andA. hybrida) collected in the flowering phase in the Tashkent Botanical Garden have been studied. They have yielded 16 alkaloids. Corydine and isocorydine have been detected in plants of this genus for the first time, and O-methyl-platycerine has been found in nature for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 204–206, March–April, 1986.  相似文献   

10.
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   

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