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1.
A comparative study of the dioxane lignins isolated from healthy and wilt-affected cotton plant stems has shown thatFusarium fungi demethylate lignin and make it more oxidized than the lignin from healthy stems.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 825–827, November–December, 1985.  相似文献   

2.
The action of catalytic amounts of anthraquinone on the alkaline hydrolysis of the stems and dioxane lignin of the cotton plant of the ssp.mexicanium has been investigated. It has been established that this leads to a substantial increase in the yield of low-molecular-weight hydrolysis products. Analysis of the monomeric fractions of the hydrolysis products by the GLC method has shown the presence in them of large amounts of substances with a p-coumaryl structure. This, and also the low level of syringyl derivatives, may be caused by the demethoxylation of the lignin under the conditions described.Institute of the Chemistry of Plant Substances, Academy of Sciences of the USSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 391–395, May–June, 1985.  相似文献   

3.
Conclusions 1. The content of lignin in the wood ofSalix viminalis andSalix acutifolia increases with the growth of the shoots during shortened days and also in drier climatic periods.2. The monosaccharides, glucose, fructose, and arabinose take part in the synthesis of the lignin of young wood ofSalix viminalis andSalix acutifolia. The formation of lignin of one-year willow wood takes place from May to January (with a maximum in June–July). The content of methoxyl groups in it gradually rises.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 6, pp. 546–550, 1969  相似文献   

4.
With the aim of revealing the specific reactions of biotransformation under lignolytic conditions, the metabolic transformation bySporotrichum pulverulentum of a number of acetophenone compounds not previously investigated that model fragments of the lignin molecule has been studied. It has been established that the metabolism of 4-hydroxyacetophenone 3-O--D-glucopyranoside takes place as a sequence of processes involving deglucosylation, the methylation of free phenolic hydroxy groups with the formation of methylated intermediates, and the further hydroxylation of the m-methylated metabolite.Irkutsk Institute of Organic Chemistry, Siberian Branch, USSR Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 987–902, November–December, 1987.  相似文献   

5.
The biodegradation reactions of veratryl- and guaiacylpropane compounds modeling structural fragments of the lignin macromolecule by the yeast-like fungusTrichosporon cutaneum D-46 have been investigated. It has been shown that the enzyme complex ofT. cutaneum is capable of catalyzing a series of reactions of the biotransformation of arylpropane substrates, namely: oxidation, the cleavage of the C-C bond of the propane chain, demethylation, and decarboxylation. The action of the enzymes was shown most actively in the case of substrates having an unsubstituted phenolic hydroxy group.Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk. Institute of Microbiology, Belorussian Academy of Sciences, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 558–564, September–October, 1992.  相似文献   

6.
    
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   

7.
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   

8.
The new alkaloid dehydroacosanine has been isolated from the roots ofAconitum sajanense Kumin, and its structure has been established by spectral and chemical methods.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 531–534, September–October, 1992.  相似文献   

9.
The component composition of extracts of the rhizomes ofRhodiola rosea has been studied by the HPLC method; the amount of rosavin has been determined and its lability on the autofermention of the raw material has been established.All-Union Scientific-Research Institute of Medicinal Plants, Scientific-Production Combine, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 188–193, March–April, 1991.  相似文献   

10.
    
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   

11.
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   

12.
Summary The decomposition of the hydrochloric acid lignin of the stems of the cotton plantGossypium hirsutum of variety 108-F by metallic sodium in liquid ammonia gives 3.8% of a mixture of phenols, among which the following were identified by GLC: dihydroeugenol, 4-hydroxy-3-methoxyphenylpropan-1-ol, (4-hydroxy-3-methoxyphenyl)ethane, (4-hydroxy-3,5-dimethoxyphenyl)propane, and 1-(4-hydroxy-3,5-dimethoxyphenyl)ethanol, and also vanillin and vanillyl alcohol.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 646–648, September–October, 1976.  相似文献   

13.
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   

14.
(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   

15.
A phospholipase A2 with a molecular mass of 12–14 kDa has been isolated from the venom of the spiderEresus niger by three-stage column chromatography. Asparagine has been identified as the N-terminal amino acid.Institute of Physiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 557–560, July–August, 1991.  相似文献   

16.
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   

17.
Two new guaiane esters — karaferin and karaferinin — have been isolated fromFerula karakalensis, and their structures and stereochemistry have been established. It has been shown that theFerula sesquiterpene alcohols angrendiol, ugamdiol, and karaferol are biogenetically interconnected and are products of a single chain of the biogenesis of terpenoids in plants.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent; Botanical Garden of Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 227–231, March–April, 1993.  相似文献   

18.
From the epigeal part of the previously unstudied plantAconitum sajanense we have isolated the new alkaloid acosanine, the structure of which has been established on the basis of spectral characteristics and has been confirmed by a direct comparison with a sample of demethyldelcorine.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 247–249, March–April, 1992.  相似文献   

19.
Summary 1. The composition of the acid fraction of the oleresin ofPinus pumila (Pall.) Regel. has been studied, and from it has been isolated, in addition to known compounds, the methyl ester of a new labdane acetoxy acid.2. In the hydrocarbon fraction of the oleoresin 11 monoterpenes and 26 sesquiterpenes have been found (and 17 of the latter have been identified).3. The composition of the fraction of neutral oxygen-containing diterpenoids fromP. pumila differs considerably in its diterpenoid components from the corresponding fractions of the oleoresins of botanically related species-P. sibirica andP. koraiensis. Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 299–302, May–June, 1976.  相似文献   

20.
An improved synthesis of the quaternary homoproaporphine alkaloid regecoline from the main alkaloid ofColchicum kesselringii Rgl. — kesselringine — has been carried out by two methods: by photochemical conversion (yield 77%) and by iodine oxidation (yield 86%). It has been shown that the iodine oxidation of homoproaporphines of the kesselringine type leads to C6a-dehydro derivatives.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 464–465, July–August, 1986.  相似文献   

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