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1.
A new cucurbitacin, endecaphyllacin C, was isolated from the tubers of Hemsleya endecaphylla. The structure was elucidated as 2β,16α,20β,25-tetrahydroxy-24-acetylaminocucurbita-5-en-3,11,22-trione (1) on the basis of extensive 1D and 2D NMR techniques, including COSY, HMBC, HMQC, and NOESY correlations, as well as HR-FAB-MS analysis.  相似文献   

2.
N-Chloroacetylcytisine was synthesized by acylation of (–)-cytisine. Stable Z- and E-conformers with respect to rotational isomerism around the N-12–CO bond were found in PMR spectra at room temperature. The point at which PMR resonances of the Z- and E-conformers coalesced upon heating was measured. The transition barrier between the conformers was estimated.  相似文献   

3.
A new 3,4-dihydroisocoumarin, named botryoisocoumarin A (1), was obtained from the fermentation culture of Botryosphaeria sp. F00741, together with two known ones, 3,8-dihydroxy-3-methylisochroman-1-one (2) and 4,8-dihydroxy-3-methylisochroman-1-one (3). Their structures were elucidated by spectroscopic analyses, including 1D and 2D NMR experiments and ESI mass spectrometry, and by comparison with those reported. Compound 1 was evaluated for its antitumor and antimicrobial activities in vitro.  相似文献   

4.
One new ten-membered lactone (1) named (Z)-4,6,9-trihydroxy-10-nonyl-3,4,5,6,9,10-hexahydrooxecin-2-one along with 5-methoxycarbonylmellein (2) and cytochalasin D (3) were isolated from the culture of the endophytic fungus strain Tubercularia sp. TF5, originally separated from the inner bark of Taxus mairei obtained in Fujian Province, Southeast China. The structures of compounds 1–3 were elucidated by spectroscopic methods. The antimicrobial and cytotoxic activities of 1 were analyzed but it showed no significant activities.  相似文献   

5.
A new compound of formula C28H48O with mp 179-180°C (aqueous ethanol) that was called eucanbin was isolated pure by column chromatography of the ethanol extract of the aerial part of Eupatorium cannabinum L. The structure 24α-methylcholest-20(21)-en-3β-ol was assigned based on chemical and spectral data. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–320, May–June, 2009.  相似文献   

6.
7.
A new cerebrogalactoside, Juglans cerebroside A (1), together with five known compounds, quercetin-3-O-β-D-galactopyranoside (2), myricetin-3-O-β-D-galactopyranoside (3), 2″E-quercetin-3-O-β-D-(6″″-O-[3″(4′″-hydroxyphenyl) propylene acyl]) glucopyranoside (4), gallic acid (5), and 2-methyl-1-hexadecanol (6) were isolated from the leaves of Juglans mandshurica Maxim. The structures of these compounds were determined by 1D, 2D NMR, and MS techniques.  相似文献   

8.
The composition of lipids from the aerial parts of two species of halophytes from the family Chenopodiaceae, Halostachys caspica C. A. Mey. and Halocharis hispida Bge. was determined. Neutral lipids (NL, 62.1 and 54.2%, respectively) dominated the total lipids (TL) of these plants. More than a third of the NL were esters of aliphatic alcohols and phytosterols (FAE). Fatty acids 16:0, 18:1, and 18:2 dominated the acids of FAE; 16:0, 18:1, and 18:3, the phospholipids. The principal fatty acids of glycolipids were unsaturated acids (68.3 and 75.1%) with linolenic acid dominating (44.9 and 43.5%). Presented at the 7th International Symposium on the Chemistry of Natural Compounds, Tashkent, October 16–18, 2007. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 276–278, May–June, 2009.  相似文献   

9.
A new nortriterpenoid (1), together with five known compounds, was isolated from Phlomis umbrosa. The structure of 1 was elucidated by spectroscopic evidence.  相似文献   

10.
A new C-glucoside, 3,4-epoxy-5-hydroxymethyl benzoate 2-C-β-glucoside (1), together with a known alkaloid, 1H-indole-3-carbaldehyde (2), were isolated from the whole plant of Commelina communis L. The structures of these compounds were determined by 1D, 2D NMR and MS techniques. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 51–52, January–February, 2009.  相似文献   

11.
A new stilbene glycoside, 5-methylresveratrol-3,4′-O-β-D-diglucopyranoside (1), was isolated from the n-butanol fraction of the rhizomes of Veratrum dahuricum, together with five known stilbenoids: resveratrol-3-O-β-D-glycoside (2), 4′-methylresveratrol-3-O-β-D-glycoside (3), oxyresveratrol-4′-O-β-D-glycoside (4), oxyresveratrol-3-O-β-D-glycoside (5), and oxyresveratrol-3,4′-O-β-D-diglycoside (6), and found for the first time in the investigated plant. The structures of six isolates were identified on the basis of 1D and 2D NMR data. Compounds 1–6 showed platelet aggregation inhibition, and compound 1 had an IC50 value of 383.6 μM against platelet aggregation induced by AA. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 279–282, May–June, 2009.  相似文献   

12.
A new flavonoid, 5,7-dihydroxy-2-(1-hydroxy-2,6-dimethoxy-4-oxo-cyclohex)-chromen-4-one (1), was isolated from the roots of Macrothelypteris torresiana (Gaud.) Ching. (Thelypteridaceae). The structure of the product was identified on the basis of detailed spectral analysis, including X-ray structure analysis.  相似文献   

13.
A new sesquiterpenoid, malloapelin D (1), and a known schizandriside (2) were isolated from the roots of Mallotus apelta. Their structures were elucidated on the basis of spectroscopic methods including IR, MS, and 1D and 2D NMR.  相似文献   

14.
A new seco-kaurane type diterpenoid, ent-3,4-seco-17-oxo-kaur-4(19),15(16)-dien-3-oic acid, and a known compound, ent-3,4-seco-kaur-4(19),16(17)-dien-3-oic acid, were isolated from the stem bark of Croton oblongifolius. The structures of these compounds were established on the basis of spectroscopic data.  相似文献   

15.
The hydrodynamic and conformational properties of molecules of poly(N,N-diallyl-N,N-dimethylammonium chloride) and N,N-diallyl-N,N-dimethylammonium chloride-maleic acid copolymers of different compositions in solutions with various ionic-strength and pH values, as well as of the polyelectrolyte complex based on the copolymer with dodecyl sulfate anions in chloroform, are studied. For poly(N,N-diallyl-N,N-dimethylammonium chloride) molecules in a 1 M NaCl solution, the Kuhn segment length and the hydrodynamic diameter of the chain are estimated as A = 3.9 nm and d = 0.48 nm, respectively. In acidic solutions with pH 3.5, the copolymers demonstrate behavior typical for polyelectrolytes. In an alkaline solution with pH 13, when 1 M NaCl is added to the solution of the copolymer containing 29 mol % maleic acid units, there is an antipolyelectrolyte effect that manifests itself as an increase in the intrinsic viscosity of the copolymer and in the hydrodynamic radius of its molecules. It is found that an increase in the fraction of maleic acid units in the copolymer from 12 to 42 mol % brings about a reduction in the equilibrium rigidity of its macromolecules from 4.1 to 2.2 nm. The equilibrium rigidity of polyelectrolyte-complex molecules is higher than that of initial copolymer molecules owing to steric interactions arising between the aliphatic chains of dodecyl sulfate anions. In an electric field, the molecules of the complex are oriented owing to the induced dipole moment resulting from the displacement of dodecyl sulfate anions along the chain contour.  相似文献   

16.
A copolymer of N,N-diallyl-N,N-dimethylammonium chloride with maleic acid of constant composition was prepared under the conditions of radical initiation. The possibility of the functionalization of the copolymer with drugs containing amino groups by polymer-analogous transformations was examined. Conditions were found for preparing conjugates of the copolymer with isoniazid. The structures and the quantitative compositions of the conjugates were determined by 13С NMR spectroscopy, and the possibility of preparing conjugates with controlled drug content was demonstrated.  相似文献   

17.
18.
A new flavonoid, kaempferol-3,4′-di-O-α-L-rhamnopyranoside (1), and three known flavonoids (2–4) were isolated from the aerial parts of T. communis L. The structure of the new compound was elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed significant antioxidant activity (IC50 187.151 ± 0.821 μM, and 92.079±0.513 μM, respectively), whereas compounds 3 and 4 showed moderate activity in DPPH free radical scavenging assays. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 295–297, May–June, 2009.  相似文献   

19.
In the search for platelet-activating-factor (PAF) antagonists, two new lignan compounds were isolated from the leaves of Syringa reticulata Hara var. mandshurica. Their structures were elucidated as (7R,8S, 8'S)-3,4,3',4'-dimethylenedioxy-8,9-dihydroxy-8.8', 7-O-9'-lignan (mandshuricol A) and (7R,8S,8'S)-3',4'methylenedioxy-4-methoxy-3,8,9-trihydroxy-8.8', 7-O-9'-lignan (mandshuricol B), Mandshuricol A and B showed antagonistic activity on PAF in the [3H] PAF receptor binding assay with IC50 values of 4.8 × 10–5 M and 3.5 × 10–5 M, respectively.  相似文献   

20.
Two new flavonoid-C-glycosides named triticuside A (1a) and triticuside B (1b) were isolated from bran of Triticum aestivum L. The structures of the two new compounds were elucidated by spectral techniques including 1H NMR, 13C NMR as well as HSQC, HMBC, and COSY. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 135–137, March–April, 2008.  相似文献   

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