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1.
Several α,ω-bifunctional derivatives of E,E,E-geranylgeraniol were prepared via convergent synthesis starting with geraniol (8), which was converted in three steps into the tetrahydropyranyl ether of 8-chlorogeraniol (9) and 8-hydroxygeranylphenylsulfone (10). Combination of synthons 9 and 10 with subsequent reductive removal of the phenylsulfonyl group produced the tetrahydropyranyl ether of ω-hydroxygeranylgeraniol (5), hydrolysis of which gave exclusively trans-ω-hydroxygeranylgeraniol (1). Derivatives 5–7 of geranylgeraniol were synthesized using standard methods. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 231–234, May–June, 2007.  相似文献   

2.
Addition of ethyl-, propyl-, and n-butylmercaptans to 1-O-allyl-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose in the presence of benzoyl peroxide catalyst was studied for the first time. The products were 1-O-(3-ethylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose, 1-O-(3-propylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose, and 1-O-(3-butylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose. Deacetylation of 1-O-(3-ethylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose produced 1-O-(3-ethylthiopropyl)-β-D-galactopyranose. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 209–211, May–June, 2007.  相似文献   

3.
Nine compounds including six cycloartane glycosides cyclosieversiosides A, B, F, G, and H and astrasieversianin IX; β-sitosterol, β-sitosterol β-D-glucopyranoside, and D-3-O-methyl-chiro-inositol were isolated and identified from roots of Astragalus sieversianus Pall. (Leguminosae) growing in the Republic of Kyrgyzstan. Presented at the 6th International Symposium on the Chemistry of Natural Compounds (SCNC, Ankara, Turkey, June 28–29, 2005. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 253–256, May–June, 2008.  相似文献   

4.
A new synthetic approach to 4E,7Z-tridecadien-1-ylacetate, a component of the Phthorimaea opercucella (Zeller) potato moth sex pheromone, was developed using a highly stereoselective Claisen rearrangement and Wittig reaction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 235–236, May–June, 2007.  相似文献   

5.
A new laboratory method for isolating the glycosides stevioside and rebaudiosides A and C from leaves of Stevia rebaudiana was proposed. According to HPLC, the glycoside contents in plants grown in Russia (Voronezh Oblast’) and Ukraine (Crimea) were 5–6% (stevioside) and 0.3–1.3% (rebaudiosides A and C). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 68–71, January–February, 2007  相似文献   

6.
The alkylation of 1,6,8-trihydroxy-3-methylanthraquinone (frangula-emodin) by α-bromoalkylmethylketones was investigated. Hydroxyls in the 1-and 8-positions of the β-derivatives were O-acylated. The compositions and structures of the prepared compounds were confirmed by elemental analysis and UV, IR, PMR, and 13C NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 324–326, July–August, 2007.  相似文献   

7.
Structures of glucofructans isolated from Cousinii radians roots were studied by methylation, periodate oxidation, and IR and 13C NMR spectroscopies. It was found that fructofuranose units were bonded to each other by inulin-type β-(2→1)-gylcoside bonds. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–5, January–February, 2007.  相似文献   

8.
A mixture of two new norditerpene alkaloids consisting of two regioisomers was isolated from the total alkaloids of Delphinium cuneatum roots. Their structures were proposed as 16-demethoxydelavaine (2a and b) on the basis of PMR, 13C NMR, IR, and mass spectra. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 467–468, September–October, 2005.  相似文献   

9.
Free and bound lipids from Helianthus tuberosus tubers were investigated. Neutral, glyco-and phospholipid classes and their fatty-acid compositions were determined. The composition of unsaponified substances was established. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–4, January–February, 2008.  相似文献   

10.
The new cycloartane glycoside cyclochivinoside C, 24S-cycloartan-3β,6α,16β,24,25-pentaol 3,16-di-O-β-D-glucopyranoside, was isolated from the aerial part of Astragalus chivensis. The structures of the isolated compounds were established by chemical transformations and PMR and 13C NMR spectra. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 460–462, September–October, 2007.  相似文献   

11.
A novel steroidal saponin, along with 12 known steroidal compounds, was isolated from the rhizomes of Paris polyphylla var. chinensis. Spectral data, including two-dimensional NMR, showed that the structure of the novel saponin was 3β,21-dihydroxypregnane-5-en-20S-(22,16)-lactone-1-O-α-L-rhamnopyranosyl(1→2)-[β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside. The isolated steroidal compounds were evaluated for their cytotoxic activity on human gastric cancer cell line HepG2, SGC7901, BxPC3. Diosgenin-3-O-α-L-rhamnopyranosyl(1→2)[α-L-rabinofuranosyl(1→4)]-β-D-glucopyranoside exhibited the most potent cytotoxic activity among the isolated steroids. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 556–560, November–December, 2007.  相似文献   

12.
Neutral substances, carbohydrates, and microelements from the aerial part of Silene viridiflora in addition to the protein content and its amino-acid composition were determined. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 365–366, July–August, 2005.  相似文献   

13.
One new flavonol glycoside named terniflonoside A (1) and four known flavonol glycosides were isolated from the whole plants of Clematis terniflora. The structure was determined by 1D and 2D NMR, ESI-MS techniques, and chemical methods. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 108–110, March–April, 2007.  相似文献   

14.
Excess enthalpies (H E) of 17 binary mixtures of o- and m-isomers of dichlorobenzene, difluorobenzene, methoxymethylbenzene, dimethylbenzene, dimethoxybenzene, aminofluorobenzene, fluoronitrobenzene, diethylbenzene, chlorofluorobenzene, fluoroiodobenzene, bromofluorobenzene, chloromethylbenzene, fluoromethylbenzene, bromomethylbenzene, iodomethylbenzene, fluoromethoxybenzene, dibromobenzene at 298.15 K were measured. All excess enthalpies measured were very small, and those of o-+m-isomers of aminofluorobenzene, dibromobenzene and iodomethylbenzene were negative but 14 other binary mixtures of isomers were positive over the whole range of mole fractions. H E of o-+m-isomers of dimethoxybenzene showed the largest enthalpic instability and those of aminofluorobenzene showed the largest enthalpic stability. There was a correlation between dipole–dipole interaction, dipole–induced dipole interaction or entropies of vaporization and excess partial molar enthalpies at infinite dilution.  相似文献   

15.
Gold nanoparticles exhibit unique optical, thermal, chemical and physical properties. The microorganisms have high potential for production of nanoparticles with wide applications. Application of fungi to produce nanoparticles is potentially exciting because of their ability to secrete large amounts of enzymes. In this study, we investigated biosynthesis of gold nanoparticles by the fungus Epicoccum nigrum isolated from Andalian gold mine in north-west of Iran. The gold nanoparticles were produced intra and extracellular by reaction of an aqueous solution of chloroauric acid with the biomass of fungus E. nigrum. The produced gold nanoparticles were in the size range of 5–50 nm in spherical and rod shapes. This is the first report on the biosynthesis of gold nanoparticles by the fungus E. nigrum.  相似文献   

16.
Analyses of the essential oils of Bunium elegans (Fenzl) Freyn and B. caroides (Boiss.) Hausskn. ex Bornm., using GC, GC/MS, and13 C-NMR spectroscopy resulted in identification of their chemical constituents. The oils of both species contain mainly the sesquiterpene hydrocarbons germacrene-D and E-caryophyllene, which amounted to 24.1% and 38% for B. elegans and 22.1% and 26.6% for B. caroides respectively. The oil of B. caroides contained the monoterpenes α-pinene and Z-β-ocimene in 4.1 and 5.9% respectively, while traces of monoterpenes were detected for B. elegans. On the other hand, in B. caroides the phenylpropanoid derivatives asaricin (7.5%) and dillapiole (10.2%) were among the major constituents. __________ Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 335–336, July–August, 2005.  相似文献   

17.
Two new phenolic glycosides named meoside-A (1) and meoside-B (2) were isolated from Lespedeza juncea. Two compounds were characterized on the basis of 1D and 2D spectral analysis and chemical derivatization. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 479–480, September-October, 2008.  相似文献   

18.
A synthesis is reported for (4R,5R)-and (4S,5S)-4-hydroxymethyl-5-(4-nitrophenyl)oxazolidin-2-ones and (1′R,4R)-and (1′S,4S)-4-[hydroxy(4-nitrophenyl)methyl]oxazolidin-2-ones from (1R,2R)-and (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediols. The effect of the experimental conditions on the formation of these compounds was studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1562–1570, October, 2007.  相似文献   

19.
A preparative method for the synthesis of first representatives of O,O-diphenyl N-sulfonylbenzimidoylphosphonates was proposed. The method involves oxidation of the corresponding α-(sulfonylamino)benzylphosphonates. The σ-constants of the N-sulfonylbenzimidoylphosphonate group were estimated by 19F NMR spectroscopy. The imidoylphosphonates obtained easily formed stable adducts at the C=N bond with P-and O-nucleophiles. Dedicated to the Corresponding Member of the Russian Academy of Sciences T. A. Mastryukova. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2567–2570, November, 2005.  相似文献   

20.
Six substances were isolated from the branches and leaves of the Chinese herb Leptopus Chinensis (Bunge) Pojark. by column chromatography for the first time. Their structures were elucidated as 3α-hydroxyfriedelan-2-one, saccharose, triacontanol, friedelane-2α,3β-diols, β-sitosterol-3-O-β-D-glucoside, and β -sitosterol on the basis of x-ray, chemical, and spectroscopic methods. __________ Published in Kimiya Prirodnikh Soedinenii, No. 5, pp. 462–464, September–October, 2005.  相似文献   

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