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1.
The 3-O-β-D-glucopyranoside of β-sitosterol (1) and the known triterpene glycosides 3-O-α-L-arabinopyranosides of oleanolic (2a) and ursolic (2b) acids and hederagenin (3), 3-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranosideofoleanolic acid (4), 3-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosides of oleanolic (5a) and ursolic (5b) acids and the newglycoside 28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranoside of 23-hydroxyursolic acid (6) were isolated from leaves of Cussonia paniculata (Araliaceae). Their structures were established using chemical methods and NMR spectroscopy.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 160–163, March–April, 2005.  相似文献   

2.
The structure of galactomannans isolated from seeds of G. delavayi and G. aquatica was studied by 1H and 13C NMR spectroscopy. It was found that the galactomannans consisted mainly of β-1-4-bound mannopyranoses, a part of which was substituted on the C-6 hydroxyl by terminal units of α-galactopyranose.__________Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 12–13, January–February, 2005.  相似文献   

3.
The known hederagenin 3-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→ 3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside (sapindoside C) and its 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl and 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl esters, new triterpene glycosides, were isolated from leaves of Kalopanax septemlobum var. maximowiczii introduced to Crimea. The structures of these compounds were established using chemical methods and two-dimensional NMR spectroscopy.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 260–262, May–June, 2005.  相似文献   

4.
Ten pure compounds, three of which were identified as β-sitosterol, β-sitosterol β-D-glucopyranoside, and D-3-O-methyl-chiro-inositol, were isolated from roots of Astragalus macropus Bunge (Leguminosae). The structure of the new cycloartane triterpenoid cyclomacrogenin B was established as 24R-cycloartan-1α,3β,7β,24,25-pentaol. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 502–504, September-October, 2008. Original article submitted May 26, 2008.  相似文献   

5.
A novel organic gel film modified electrode was simply and conveniently fabricated by casting LixMoOy and polypropylene carbonate (PPC) onto the surface of a gold electrode. The cyclic voltammetry and amperometry studies demonstrated that the LixMoOy film modified electrode has a high stability and a good electrocatalytic activity for the reduction of iodate. In amperometry, a good linear relationship between the steady current and the concentration of iodate was obtained in the range from 3×10–7 to 1×10–4 mol L–1 with a correlation coefficient of 0.9997 and a detection limit of 1×10–7 mol L–1.  相似文献   

6.
Five triterpenoid saponins were isolated from the stems of Hedera colchica K. Koch (Araliaceae). Two of them are new natural substances. HCS-A (1): 3-O-α-L-arabinopyranoside, 28-O-α-L-rhamnopyranosyl-(1→ 4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-arjunolic acid. HCSt-B (2):3-O-β-D-xylopyranoside, 28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-hederagenin. A derivative of arjunolic acid is described for the first time in the Araliaceae family. The chemical structures of isolated compounds were established on the basis of chemical and 1D and 2D NMR experiments.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 39–41, January–February, 2005.  相似文献   

7.
Eight known glycosides of hederagenin and the new triterpene glycoside 3-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin were isolated by chromatographic methods from leaves of Kalopanax septemlobum var. maximowichii introduced to Crimea. The known 3-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin was observed for the first time in Kalopanax septemlobum.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 156–159, March–April, 2005.  相似文献   

8.
Lithiation of O-functionalized alkyl phenyl sulfides PhSCH2CH2CH2OR (R = Me, 1a; i-Pr, 1b; t-Bu, 1c; CPh3, 1d) with n-BuLi/tmeda in n-pentane resulted in the formation of α- and ortho-lithiated compounds [Li{CH(SPh)CH2CH2OR}(tmeda)] (α-2ad) and [Li{o-C6H4SCH2CH2CH2OR)(tmeda)] (o-2ad), respectively, which has been proved by subsequent reaction with n-Bu3SnCl yielding the requisite stannylated γ-OR-functionalized propyl phenyl sulfides n-Bu3SnCH(SPh)CH2CH2OR (α-3ad) and n-Bu3Sn(o-C6H4SCH2CH2CH2OR) (o-3ad). The α/ortho ratios were found to be dependent on the sterical demand of the substituent R. Stannylated alkyl phenyl sulfides α-3ac were found to react with n-BuLi/tmeda and n-BuLi yielding the pure α-lithiated compounds α-2ac and [Li{CH(SPh)CH2CH2OR}] (α-4ab), respectively, as white to yellowish powders. Single-crystal X-ray diffraction analysis of [Li{CH(SPh)CH2CH2Ot-Bu}(tmeda)] (α-2c) exhibited a distorted tetrahedral coordination of lithium having a chelating tmeda ligand and a C,O coordinated organyl ligand. Thus, α-2c is a typical organolithium inner complex.Lithiation of O-functionalized alkyl phenyl sulfones PhSO2CH2CH2CH2OR (R = Me, 5a; i-Pr, 5b; CPh3, 5c) with n-BuLi resulted in the exclusive formation of the α-lithiated products Li[CH(SO2Ph)CH2CH2OR] (6ac) that were found to react with n-Bu3SnCl yielding the requisite α-stannylated compounds n-Bu3SnCH(SO2Ph)CH2CH2OR (7ac). The identities of all lithium and tin compounds have been unambiguously proved by NMR spectroscopy (1H, 13C, 119Sn).  相似文献   

9.
Under natural conditions gold has low solubility that reduces its bioavailability, a critical factor for phytoextraction. Researchers have found that phytoextraction can be improved by using synthetic chelating agents. Preliminary studies have shown that desert willow (Chilopsis linearis), a common inhabitant of the Chihuahuan Desert, is able to extract gold from a gold-enriched medium. The objective of the present study was to determine the ability of thiocyanate to enhance the gold-uptake capacity of C. linearis. Seedlings of this plant were exposed to the following hydroponics treatment: (1) 5 mg Au L–1 (2.5×10–5 mol L–1), (2) 5 mg Au L–1+10–5 mol L–1 NH4SCN, (3) 5 mg Au L–1+5×10–5 mol L–1 NH4SCN, and (4) 5 mg Au L–1+10–4 mol L–1 NH4SCN. Each treatment had its respective control. After 2 weeks we determined the effect of the treatment on plant growth and gold content by inductively coupled plasma–optical emission spectroscopy (ICP–OES). No signs of shoot-growth inhibition were observed at any NH4SCN treatment level. The ICP–OES analysis showed that addition of 10–4 mol L–1 NH4SCN increased the concentration of gold by about 595, 396, and 467% in roots, stems, and leaves, respectively. X-ray absorption spectroscopy (XAS) studies showed that the oxidation state of gold was Au(0) and that gold nanoparticles were formed inside the plants.  相似文献   

10.
(±)-5,2′-Dihydroxy-6,7,6′-trimethoxyflavanone, (-)-5,2′-dihydroxy-6,7,8,6′-tetramethoxyflavanone, chrysin, wogonin, apigenin, isoscutellarein, scutellarein, cosmosiin, and the new flavonoid wogonin-7-O-β-D-glucopyranoside, the structure of which was established using chemical transformations and spectral data, were isolated from Scutellaria immaculata roots.__________Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 26–28, January–February, 2005.  相似文献   

11.
Among the perovskites, the rare earth manganites find application in several electrochemical devices because of their enhanced thermodynamic stability. In this paper, we present the results obtained on the preparation and characterization of La0.95MnO3+δ and Sm0.95MnO3+δ which were prepared by the solid state and sol–gel methods. XRD characterization of the manganites indicated that the crystal structure depends on the method of preparation and heat treatments. The ratio of Mn3+ to Mn4+ in these samples also depended on the method of preparation and heat treatments, as indicated by thermogravimetric (TG) and temperature programmed reduction (TPR) studies in Ar + 5% H2 atmosphere. The standard molar enthalpy of formation, which is a measure of the thermodynamic stability of these compounds were determined using an isoperibol calorimeter.  相似文献   

12.
Two new compounds of the AxMOXO4 family, β-LiVOAsO4 and β-VOAsO4, have been synthesized by solid state reaction and electrochemical lithium deintercalation from β-LiVOAsO4, respectively. Both compounds are isostructural and are built like other β-VOXO4 (X=S, P) by (VO5) chains of distorted VO6 octahedra connected via corner-shared AsO4 tetrahedra. For β-LiVOAsO4 the additional Li+ ions occupy chains of edge-shared octahedra running perpendicularly to the (VO5) chains. The one-dimensional antiferromagnetic behavior suggested by the structure has been experimentaly confirmed. It is shown that lithium deintercalation occurs through a first-order transition at 4.02 V vs Li+/Li0. From chemical bond considerations it is shown why the redox potential of a given transition element M in a six-fold coordination involving (M=O)m+ units lies between those observed in oxides and in M2(XO4)3 compounds with (XO4)n oxo anions (X=S, P, As).  相似文献   

13.
Hydrolyzed tannin (I), the structure of which was established using chemical investigations and UV, IR, PMR and 13C NMR spectra, was isolated from Euphorbia glareosa leaves.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 250–251, May–June, 2005.  相似文献   

14.
Water-distilled essential oil from the aerial parts of Nepeta oxyodonta Boiss. was analyzed by GC/MS for the first time. Fifty-eight components were identified. The major components were (E)-caryophyllene (12.6%), spathulenol (8.5%), β-bourbonene (8.1%), germacrene-D (7.4%), α-cadinol (7.3%), germacrene-D-4-ol (6.8%), T-cadinol (5.6%), and caryophyllene oxide (5.3%).__________Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 141–142, March–April, 2005.  相似文献   

15.
Ferula gummosa Boiss. (Apiaceae) fruit volatile oil was analyzed by GC/MS. Seventy-three components (96.89%) were identified, and the major components were β-pinene (43.78%), α-pinene (27.27%), and myrcene (3.37%). The antimicrobial activity of the oil was tested on three strains of Gram positive bacteria (Staphylococcus aureus, S. epidermis, and Bacillus subtilis), three strains of Gram negative bacteria (Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa), and two strains of fungi (Candida albicans and C. kefyr). The essential oil remarkably inhibited the growth of the tested microorganisms. The results indicate that the fruits have potential for use as an aromatic antimicrobial agent.__________Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 252–254, May–June, 2005.  相似文献   

16.
The essential oil of Helichrysum italicum (Roth) G. Don from Croatia has been fractionated into terpene and terpenoid fractions and analyzed using GC/MS. Fifty-two compounds were identified. The main hydrocarbons of the oil were α-pinene (10.2%), α-cedrene (9.6%) aromadendrene (4.4%), β-caryophyllene (4.2%), and limonene (3.8%), while the main oxygen-containing compounds were neryl acetate (11.5%), 2-methylcyclohexyl pentanoate (8.3%), 2-methylcyclohexyl octanoate (4.8%), and geranyl acetate (4.7%). The essential oil and its terpene and terpenoid fractions were evaluated for antibacterial and antifungal activities. The screening of antimicrobial activity was conducted by a disc diffusion test and the minimum inhibitory concentration was determined against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The essential oil and its terpenoid fraction exhibited higher antimicrobial activity with respect to the terpene fraction. The antimicrobial activities of the oil and its terpenoid fraction were more pronounced against Staphylococcus aureus and Candida albicans.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 29–32, January–February, 2005.  相似文献   

17.
The fatty acid composition of seed extracts of Salvia bracteata, S. aethiopis, and S. candidissima ssp. candidissima were analyzed by GC/MS. The main compound of S. bracteata, S. aethiopis, and S. candidissima ssp. candissima was found to be 9,12-octadecenoic acid at 64.3%, 73.4%, and 20.8%, respectively. The seed extracts of S. bracteata showed activity against S. aureus E. coli, M. smegmatis, and C. albicans with MIC values of 1.1, 0.5, 1.1, and 1.1 mg/mL, respectively, while the seeds extract of S. aethiopis showed activity against the same microorganisms with MIC values of 2.2, 2.2, 1.1, and 1.1 mg/mL, respectively. However, the seed extract of S. candidissima ssp. candidissima showed activity only against M. smegmatis with a MIC value of 0.25 mg/mL.__________Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 223–225, No. 3, May–June 2005.  相似文献   

18.
The dried and aerial part of Linum mucronatum ssp. mucronatum was analyzed by gas chromatography-mass spectrometry (GC-MS). Two aryltetralin lignans, podophylloyoxin, 6-methoxypodophylloyoxin, and β-peltatin, were identified. This is the first report of the analysis of L. mucronatum ssp. mucronatum.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 24–25, January–February, 2005.  相似文献   

19.
The far-infrared spectra (350–35 cm–1) of gaseous ethyl methyl ether-d 0 and ethyl methyl-d 3-ether have been recorded at a resolution of 0.10 cm–1. For the d 0 species, the fundamental asymmetric torsion of the more stable trans conformer (two methyl moieties are trans to one another) has been observed at 115.40 cm–1 with four upper state transitions falling to lower frequency, whereas, for the gauche form, it has been observed at 93.56 cm–1 with two excited states falling to lower frequency. the corresponding series for the d 3 species start from 106.00 and 87.10 cm–1, respectively. From these data, the asymmetric torsional potential coefficients for the d 0 species have been determined to be: V 1 = 572 ± 30; V 2 = 85 ± 8; V 3 = 619 ± 30; V 4 = 175 ± 18, and V 6 = –28 ± 3 cm–1. The trans to gauche and gauche to gauche barriers were calculated to be 958 cm–1 (11.5 kJ/mol) and 631 cm–1 (7.55 kJ/mol), respectively, with an energy difference of 550 ± 6 cm–1 (6.58 ± 0.07 kJ/mol). Utilizing three conformer pairs, variable temperature studies (–105 to –150°C) of the infrared spectra of the d 0 sample dissolved in liquid krypton gave an enthalpy difference of 547 ± 28 cm–1 (6.54 ± 0.33 kJ/mol) with the trans conformer the more stable rotamer. It is estimated that there is only 4% of the gauche conformer present at ambient temperatures. The structural parameters, conformational stabilities, barriers to internal rotation, and fundamental vibrational frequencies, which have been determined experimentally, are compared to those obtained from ab initio gradient predictions from RHF/6-31G* and with full electron correlation at the MP2 level with three different basis sets. The adjusted r 0 structural parameters have been obtained for the trans conformer from combined ab initio MP2/6-311+G** predictions and previously reported microwave rotational constants. The reported distances should be accurate to 0.003 Å and the angles to 0.5°. These results are compared to the corresponding quantities obtained for some similar molecules.  相似文献   

20.
In this work we report about a new rare-earth oxoborate β-Dy2B4O9 synthesized under high-pressure/high-temperature conditions from Dy2O3 and boron oxide B2O3 in a B2O3/Na2O2 flux with a walker-type multianvil apparatus at 8 GPa and 1000°C. Single crystal X-ray structure determination of β-Dy2B4O9 revealed: , a=616.2(1) pm, b=642.8(1) pm, c=748.5(1) pm, α=102.54(1)°, β=97.08(1)°, γ=102.45(1)°, Z=2, R1=0.0151, wR2=0.0475 (all data). The compound exhibits a new structure type which is built up from bands of linked BO3- (Δ) and tetrahedral BO4-groups (□). The Dy3+-cations are positioned in the voids between the bands. According to the conception of fundamental building blocks β-Dy2B4O9 can be classified with the notation 2Δ6□:Δ3□=4□=3□Δ. Furthermore we report about temperature-resolved in situ powder diffraction measurements and IR-spectroscopic investigations on β-Dy2B4O9.  相似文献   

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