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1.
Two new amide alkaloids were isolated from the alkaloidal fraction of Datura metel L. Their structures were elucidated as (E)-methyl 4-(3-(4-hydroxyphenyl)-N-methylacrylamido) butanoate and 6,7-dimethyl-1-D-ribityl-quinoxaline-2,3(1H,4H)-dione-5′-O-β-D-glucopyranoside on the basis of spectroscopic methods including HRESIMS, 1D and 2D NMR. Tropane alkaloids have for a long time been considered as characteristic ingredients of D. metel. However, the presence of amide alkaloids in D. metel was reported for the first time in this study.  相似文献   

2.
A novel anthocyanidin glycoside, abacopterin J (1), together with the known eruberin B (2) and eruberin C (3) was isolated from the fern Abacopteris penangiana (Hook.) Ching. The structure of the new compound 1 was elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, 1H–1H COSY and ROESY, and chemical evidence. Abacopterin J is the first example of an anthocyanidin glycoside isolated from natural sources, which is comprised of a flavan and an anthocyanidin moiety.  相似文献   

3.
Two new flavones were isolated from the aerial parts of Retama raetam subsp. raetam. Their structures were established as luteolin 4′-O-neohesperidoside (1) and 5,4′-dihydroxy-(3″,4″-dihydro-3″,4″-dihydroxy)-2″,2″-dimethylpyrano-(5″,6″:7,8)-flavone (2) by means of spectroscopic methods. Also present was ephedroidin (4′,5,7-trihydroxy-8-(2-hydroxy-3-butenyl)-flavone).  相似文献   

4.
Yan Wang  Ziyang Lou  Qing-Bin Wu  Mei-Li Guo   《Fitoterapia》2010,81(8):1246-1252
A new saponin, cristatain (1), together with four other saponins, celosin A (2), celosin B (3), celosin C (4) and celosin D (5) were isolated from the seeds of Celosia cristata L. (Amaranthaceae). Their structures were established by chemical and spectroscopic analyses. For the first time, the saponins were found in C. cristata L. In addition, compound 1 exhibited significant hepatoprotective effect on carbon tetrachloride (CCl4)- and N,N-dimethylformamide (DMF)–induced hepatotoxicity in mice, which were evidenced by significant decreases in the values of asparate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) of serum and histopathological examinations compared to controls.  相似文献   

5.
Two new furostanol glycosides, named tribufurosides I (1) J (2), were isolated from the fruits of Tribulus terrestris L. by a combination of chemical and spectroscopic methods. Its structures were established as 26-O-β-d-glucopyranosyl-(25S)-5α-furost-12-one-2α,3β,22α,26-tetraol-3-O-β-d-glucopyranosyl (1 → 2)-β-d-glucopyranosyl (1 → 4)-β-d-galactopyranoside (1) and 26-O-β-d-glucopyranosyl-(25R)-5α-furost-20(22)-en-12-one-2α,3β,26-triol-3-O-β-d-glucopyranosyl (1 → 4)-β-d-galactopyranoside (2).  相似文献   

6.
Two new 27-hydroxy-oleanolic acid type triterpenoid saponins, raddeanoside 20 (1) and raddeanoside 21(2) were isolated from the rhizome of Anemone raddeana Regel. The structures of the two compounds were elucidated as 27-hydroxy-oleanolic acid 3-O-α-l-rhamnopyranosyl(1→2) [β-d-glucopyranosyl (1→4)]-α-l-arabinopyranoside (1) and 3-O-α-l-rhamnopyranosyl (1→2)-α-l-arabinopyranosyl-27-hydroxy-oleanolic acid 28-O-α-l-rhamnopyranosyl(1→4)-β-d-glucopyranosyl (1→6)-β-d-glucopyranoside (2) on the basis of chemical and spectral evidence.  相似文献   

7.
A new isocoumarin, 7-hydroxyl-4-methyl isocoumarine (1), together with three known monoterpenes, (3R, 4R, 6S)-3, 6-dihydroxy-1-menthene (2), (+)-(1R, 3S, 4R, 6S)-6-hydroxymenthol (3) and 4-isopropyl-1-methylcyclohex-2-ene-1, 6-diol (4), was isolated from the methanol extract of Brickellia rosmarinifolia. The structures were determined by spectroscopic means. Compounds 1, 2, 3 and 4 showed antifungal activities against Colletotrichum musae and Peronophythora litchii in vitro.  相似文献   

8.
Two new clerodane diterpenoids 2β-methoxy-cleroda-3,13-dien-18-carboxy-15,16-olide (1) and 15ξ-methoxy-cleroda-3,12-dien-18-carboxy-15,16-olide (2) and one new nitrogen-containing clerodane diterpenoid 15-oxo-echinophyllin A (3), along with six known compounds, namely, echinophyllin A, (−)-patagonic acid, tyrosol, oplopanone, 4-hydroxy-4-methyl-2-[(1R)-1-(1-methylethyl)-4-oxopentyl]-2-cyclohexen-1-one and 1β,6α-dihydroxy-eudesman-4(15)-ene were isolated from the leaves of Casearia sylvestris. Their structures were determined by extensive NMR techniques.  相似文献   

9.
A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC50 value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC50 values of 2.12 and 3.71 µg/ml, respectively.  相似文献   

10.
Two new bergenin derivatives, named rivebergenin A and B (1, and 2), together with two known compounds, bergenin (3) and norbergenin (4) were isolated from the stem of Rivea hypocrateriformis (Desr.) Choisy. The structures of the new compound have been assigned from 1H and 13C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Compounds 1-4 showed the strong antioxidant activity.  相似文献   

11.
Phytochemical investigation of the stem bark of Terminalia mollis afforded friedelin (1), catechin with epicatechin (2), gallocatechin with epigallocatechin (3) and 3-O-methylellagic acid 4'-O-α-rhamnopyranoside (4). Arjunolic acid with 2α, 3β, 23-trihydroxy-urs-12-en-28-oic acid (5), 2α-hydroxyursolic acid (6), gallic acid (7), chebulanin (8) and 2'-O-galloylvitexin (9) were isolated from the leaf. Chebulanin (8), betulinic acid (10), ursolic acid (11), catechin (12), isoorientin (13), orientin (14), isovitexin (15) and punicalagin (16) were isolated from Terminalia brachystemma leaf. The first full unambiguous NMR assignments for (4) and (8), and revised assignments for (9), are reported. Compound (16) showed good activity against three Candida species.  相似文献   

12.
Ying Xu  Zeng Jun Guo  Nan Wu 《Fitoterapia》2010,81(8):1091-1093
Two new amide alkaloids, named 3-isopropyl-tetrahydropyrrolo [1,2-a] pyrimidine-2,4(1H,3H)-dione (1) and 1-acetyl-2,3,6-triisopropyl-tetrahydropyrimidin-4(1H)-one (2), were isolated from the roots of Aconitum taipeicum. Their chemical structures were characterized on the basis of MS, 1D- and 2D NMR. The anti-leukaemia activities of the compounds were also tested. The results indicated that the compounds exhibited more significant cell growth inhibitory activities against HL-60 cells than adriamycin, with the IC50 of 1.1 ± 0.03 μg/mL and 1.6 ± 0.07 μg/mL respectively. In addition, two compounds showed anti-tumor activities against K562 cells as well.  相似文献   

13.
Zhao ZX  Jin J  Lin CZ  Zhu CC  Liu YM  Lin AH  Liu YX  Zhang L  Luo HF 《Fitoterapia》2011,82(7):1102-1105
Two new chalcone glycosides 4′-O-(6″-O-galloyl-β-d-glucopyranosyl)-2′,4-dihydroxychalcone (1) and 4′-O-(6″-O-galloyl-β-d-glucopyranosyl)-2′-hydroxy-4-methoxychalcone (2) together with one known chalcone glycoside 4′-O-β-d-glucopyranosyl-2′-hydroxy-4-methoxychalcone (3) were isolated from the stems of Entada phaseoloides. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, 1H–1H COSY, and chemical evidences. This is the first report of chalcone-type compounds isolated from the genus Entada.  相似文献   

14.
A new glycocerebroside (1), along with one reported one (2), was isolated from the ethanol extract of Sagina japonica (Caryophyllaceae) and was fully characterized. The structures of two compounds were identified as (2S, 3S, 4R, 8E)-1-(β-D-glucopyranosyl-3, 4-dihydroxy-2-[(R)-2′- hydroxypalmitoyl]amino-8-heptadecaene (1) and (2S, 3R, 8E)-1-(β-D-glucopyranosyl-3-hydroxy-2-[(R)-2′-hydroxypalmitoyl]amino-8-octadecaene (2) by using spectroscopic methods (1H, 13C, and 2D NMR, MS) and chemical degradation.  相似文献   

15.
Studies on the chemical constituents of leaves of Camellia oleifera Abel. led to the isolation of 3 new bibenzyl glycosides. Their structures have been elucidated as 1-(3′,5′-dihydroxy)phenyl-2-(4″-O-β-D-glucopyranosyl)phenylethane (1), 1-(3′,5′-dimethoxy)phenyl-2-(4″-O-β-D-glucopyranosyl)phenylethane (2) and 1-(3′,5′-dimethoxy)phenyl-2-[4″-O-β-D-glucopyranosyl(6→1)-O-α-L-rhamnopyranosyl]phenylethane (3) through spectral studies including HR-ESI-MS, 1H NMR, 13C NMR and 2D NMR experiments. All the above 3 bibenzyl glycosides showed cytotoxic activities to Hela and hep2 cell lines.  相似文献   

16.
Wood samples of apitong (Dipterocarpus grandiflorua) and ilang-ilang (Ilang-Ilang C. dadloyi) and feces of termites [Cryptotermes brevis (Walker)] fed on these woods were collected from University of the Philippines, Los Baňos. Lignin of each sample was isolated by Björkman’s procedure. There was no significant difference in 1H nuclear magnetic resonance (NMR) spectra or in the methoxyl content between Björkman lignins from original woods and termite feces. Differences were detected in the contents of aliphatic and unconjugated phenolic hydroxyl groups, suggesting minor structural changes of lignin during digestion by termites. In addition, the ratio of syringyl to guaiacyl nuclei of Björkman lignin from termite feces determined by 1H NMR spectra was higher than those from the original woods. The molar ratio of syringyl to guaiacyl nuclei of termite feces was higher than those from the original woods as determined by alkaline nitrobenzene oxidation. These results suggest that the structural changes of lignin in the termite gut are due to the insignificant formation of C-C linkages in guaiacyl nuclei. It was concluded that there were minor changes in the structural features of lignin under mostly anaerobic conditions, in contrast to the significant changes that occur through biological modification under aerobic conditions.  相似文献   

17.
A new cerebroside, 1-O-β-d-glucopyranosyl-(2S,3S,4R,10E)-2-[(2′R)-2′-hydroxyltricosanoyl-amino]-10-octadecene-1,3,4-triol was isolated from the aerial parts of Gynura divaricata DC.  相似文献   

18.
Pathogenicity of Lecanicillium muscarium, against Eretmocerus sp. nr. furuhashii (Hymenoptera: Aphelinidae), was investigated under laboratory conditions to determine if the fungal infection of the whitefly host can effect the survival, longevity and fecundity of female parasitoid. The results indicated that the number of parasitized larvae surviving a L. muscarium treatment after 6 days of oviposition decreased with increasing concentrations of L. muscarium and in later stages of development (12 days post oviposition) were not affected by fungal application. There were no significant differences on adult parasitoid survivorship after 7 days among all treatments. Maximum survivorship (73.33%) was observed for control and it was minimum (60%) at 1 × 108 conidia/ml. L. muscarium showed a non significant effect on longevity and next offsprings of female parasitoids. The percentage emergence of parasitoids from the whitefly nymphs produced by the females emerged from treated pupae was almost similar. Maximum emergence (69.77%) was observed at 1 × 106 conidia/ml and it was lowest (61.02%) at conidial concentration of 1 × 108 conidia/ml. Maximum longevity of adult Eretmocerus sp. emerging from whitefly nymphs when treated after 12 days of postoviposition was observed for 1 × 105 conidia/ml having a mean value of 5 days whereas the lowest longevity was 4.9 days observed at 1 × 108 conidia/ml. The results mentioned above indicate that the interaction among biocontrol agents is positive to a greater extent with minimum risk hazards.  相似文献   

19.
A new abietane diterpene, glypensin A (1) and four known compounds, 12-acetoxy-ent-labda-8(17), 13E-dien-15-oic acid (2), quercetin 3-O-α-L-arabinofuranoside (3), quercetin 3-O-β-D-galactopyranoside (4), β-sitosterol (5) were isolated from the branches and leaves of Glyptostrobus pensilis (Staut.) Koch. Their structures were determined by MS, 1D- and 2D-NMR means. Compound 1 showed cytotoxicity on human chronic myeloid leukemia cell line K562 (IC50 = 21.2 μM).  相似文献   

20.
A polysaccharide, a glucan with mean Mr of 1.0×106 (MP1), was isolated from the mesocarp of fruits of Orbignya phalerata. Chemical and spectroscopic studies indicated that MP1 has a highly branched glucan type structure composed of α-(1→4) linked -glucopyranose residues with (3→4), (4→6), and with (3→6) branching points. MP1 enhanced phagocytosis in vivo and exhibited anti-inflammatory activity.  相似文献   

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