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1.
The phytochemical investigation of the roots of Euphorbia bupleuroides Desf. (Euphorbiaceae) yielded three new compounds named 4,20-dideoxy(4α)phorbol-12-benzoate-13-isobutyrate (1), 25-hydroperoxycycloart-3β-ol (2), and 3β,7β-dihydroxy-4α,14α-dimethyl-8β,9β-epoxy-5α-ergosta-24(28)-ene (3), together with 17 known compounds 4–20. Their structures were established from analysis of 1D (1H, 13C and DEPT) and 2D NMR (COSY, HSQC, HMBC and NOESY) data, and of mass spectrometry (HRESIMS), and by comparison with literature data. 相似文献
2.
《Phytochemistry letters》2008,1(2):85-88
The phytochemical investigation of the methylene chloride/methanol extract of the aerial parts of Artemisia herba-alba afforded two new natural sesquiterpene lactones 1β,9β-diacetoxyeudesm-3-en-5α,6β,11βH-12,6-olide (1) and 1β,9β-diacetoxyeudesm-4-en-6β,11βH-12,6-olide (2). The structures of the compounds were determined by comprehensive NMR studies, including DEPT, COSY, NOESY, HMQC, HMBC and HRMS. 相似文献
3.
Xiaoyu Wang Lianli Sun Kexin Huang Shuyun Shi Lijuan Zhang Juanhua Xu Hua Peng Xianfeng Sun Liwei Wang Xiumei Wu Yu Zhao Xiaokun Li Joachim Stöckigt Jia Qu 《化学与生物多样性》2009,6(7):1053-1065
A phytochemical investigation of the roots of Ligularia atroviolacea resulted in the isolation of 24 compounds including seven new eremophilanoids named eremophila‐3,7(11),8‐triene‐12,8;14,6α‐diolide ( 1 ), 3β‐(angeloyloxy)eremophil‐7(11)‐en‐12,8β‐olid‐14‐oic acid ( 2 ), 1α‐chloro‐10β‐hydroxy‐6β‐(2‐methylpropanoyloxy)‐9‐oxo‐7,8‐furoeremophilane ( 3 ), (10βH)‐8‐oxoeremophila‐3(4),6(7)‐diene‐12,14‐dioic acid ( 4 ), (10αH)‐8‐oxoeremophila‐3(4),6(7)‐diene‐12,14‐dioic acid ( 5 ), 8β‐[eremophila‐3′,7′(11′)‐diene‐12′,8′α;14′,6′α‐diolide]eremophila‐3,7(11)‐diene‐12,8α;14,6α‐diolide ( 6 ), and ligulatrovine A ( 7 ), eleven known eremophilanoids, 8 – 18 , four steroids, one glucose derivative, and one fatty acid. The structures of these compounds were elucidated by spectroscopic methods including 2D‐NMR experiments. The structure of 3 was also established by an X‐ray diffraction study. The in vitro cytotoxicity evaluation of selected compounds was performed on seven cultured tumor cell lines, i.e., KB, BEL‐7404, A549, HL‐60, HeLa, CNE, and P‐388D1. The preliminary taxonomy of this species was also discussed, and the possible biogenesis of a dimer possessing a new noreremophilanoid type skeleton, 7 , is presented in a preliminary form. 相似文献
4.
In this study the red flowers of Canna indica (Cannaceae) were extracted by using sonicator and isolation of anthocyanins have been carried out. Four anthocyanin pigments have been isolated apart from quercetin and lycopene. They are Cyanidin-3-O-(6′′-O-α-rhamnopyranosyl)-β-glucopyranoside (1), Cyanidin-3-O-(6′′-O-α-rhamnopyranosyl)-β-galactopyranoside (2), Cyanidin-3-O-β-glucopyranoside (3) and Cyanidin-O-β-galactopyranoside (4). These compounds were isolated by using HPLC and their structures were subsequently determined on the basis of spectroscopic analyses, i.e., 1H NMR, 13C NMR, HMQC, HMBC, ESI-MS, FTIR, UV–Visible etc. The isolated compounds showed good antioxidant activity thus makes it suitable for use in food coloration and as a nutraceutical. Thus it is a promising pigment source for food applications. 相似文献
5.
Ergosterol, episterol, 4α-methyl-5α-ergosta-8,24(28)-dien-3β-ol and 24-methylene-24,25-dihydrolanosterol, isolated from Phycomyces blakesleeanus grown in the presence of methionine-[methyl-2H3], each contained two deuterium atoms; lanosterol, however, was unlabelled. The 14C:3H atomic ratio of the following sterols isolated from P. blakesleeanus grown in the presence of mevalonic acid-[2-14C,(4R)-4-3H1], was: ergosterol, 5:3; episterol, 5:4; ergosta-5,7,24(28)-trien-3β-ol, 5:3; 4α-methyl-5α-ergosta-8,24(28)-dien-3β-ol, 5:4; 24-methylene-24,25-dihydrolanosterol, 6:5; lanosterol, 6:5. The significance of these results in terms of ergosterol biosynthesis is discussed. 相似文献
6.
A bio-assay guided fractionation of Piper garagaranum C. DC. led to the isolation of two prenylated hydroxybenzoic acids (1-2) with anti-inflammatory and cytotoxic activities. The anti-inflammatory action was determined in an LPS stimulated RAW 264.7 murine macrophage assay with IC50 values for inhibition of NO production of (18 ± 3) and (26 ± 5) μM, for 1 and 2, respectively. These compounds do not inhibit NO production by a competitive inhibition of the iNOS enzyme and show anti-inflammatory properties by lowering the expression of pro-inflammatory genes (TNF-α, IL-1β, CXCL2 and CCL2), as determined by qRT-PCR. Electrochemical measurements using cyclic voltammetry (CV) show that compound 1 exhibits anti-oxidant properties. This is the first phytochemical study of this plant, and we report a preliminary study of the biological activity of the isolated compounds. 相似文献
7.
From the roots of Xylopia nitida, were obtained a new natural diterpene, the ent-kaur-16-en-18,19-diol and a new aporphine alkaloid, the 5,6,6a,7-tetrahydro-1-methoxy-(6aS)-4H-benzo[de][1,3]benzodioxolo [5,6-g]quinoline. Some known compounds were also isolated, ent-trachylobane, ent-trachyloban-18,19-diol, ent-trachyloban-18-oic acid, ent-trachyloban-19-oic acid, (−)-xylopine, 1-O-ethyl-β-D-glucopyranose and a mixture of β-sitosterol and stigmasterol. This is the first phytochemical study about X. nitida. In this paper chemotaxonomic significance of these compounds is discussed. 相似文献
8.
Diabetes is a non-communicable disease, which occurs either due to the lack of insulin or the inability of the human body to recognize it. The recent data indicates an increase in the trend of people diagnosed with Type 2 diabetes mellitus (T2DM). α-Glucosidase inhibitors are known to reduce the impact of carbohydrates on blood glucose level and prevent the digestion of carbohydrates. α-glucosidase inhibitors hold great potential for the treatment of T2DM. In search of better α-glucosidase inhibitors, a series of novel (R)-4-fluorophenyl-1H-1,2,3-triazole derivatives were synthesized (6 and 8a-n) and evaluated for their α-glucosidase inhibitory activity in vitro. All new compounds were characterized by 1H NMR, 13C NMR, 19F NMR, ESI-MS, and where applicable by single crystal X-ray diffraction (8 m). A preliminary structure-activity relationship suggested that the presence of 1H-1,2,3-triazole ring in (R)-4-fluorophenyl-1H-1,2,3-triazole derivatives has remarkable contribution in the overall activity. Molecular docking studies were carried out to investigate the binding mode of compounds within the active site of the α-glucosidase enzyme. Docking results are in complete agreement with the experimental finding. This study unravelled a new class of triazole derivatives with α-glucosidase inhibitory activity. 相似文献
9.
Lactuca indica L. (Compositae) has been used as a folk medicine for the treatment of intestinal disorders. Phytochemical constituents of L. indica were investigated, and their antioxidant and α-glucosidase inhibitory activities thoroughly studied. A phytochemical investigation of the aerial parts of L. indica resulted in the isolation and identification of eight phenolic compounds. The structures of the compounds were elucidated on the basis of spectroscopic evidence as apigenin, luteolin, isoquercitrin, chlorogenic acid, protocatechuic acid, p-hydroxymethyl benzoic acid, trans-cinnamic acid, and p-coumaric acid. Luteolin, isoquercitrin, chlorogenic acid, and p-hydroxymethyl benzoic acid showed antioxidant activities with IC50 values in the range of 35.5–52.5 μM. In addition, apigenin and luteolin showed α-glucosidase inhibition activities with IC50 values of 96.4 and 100.7 μM, respectively. These findings strongly suggest that L. indica is a potential source of natural antioxidants and/or anti-diabetic agents in pharmaceutical and health functional foods. 相似文献
10.
A phytochemical analysis of Dianthus erinaceus Boiss. var. erinaceus (Caryophyllaceae) has led to the isolation of two novel triterpenoid saponins, containing an oleane type skeleton, named dianosides K and L (1, 2), along with six known triterpenoid saponins (3–8). On the basis of chemical and spectrometric data, the structures of the new compounds were elucidated as 3-O-[β-d-glucopyranosyl (1 → 3)]–[β-d-glucopyranosyl (1 → 6)]-β-d-glucopyranosyl-olean-12-ene-23α,28-β–dioic acid 28-O-β-d-glucopyranosyl ester (1) and 3-O-[β-d-glucopyranosyl (1 → 3)]–[β-d-glucopyranosyl(1 → 6)]-β-d-glucopyranosyl-olean-12-ene-23α,28-β-dioic acid 28-O-α-l-mannopyranosyl (1 → 6)-β-d-glucopyranosyl ester (2). All isolated natural compounds were structurally characterized by 1D- (1H, 13C, DEPT); 2D- (COSY, HMQC, HMBC) NMR and HR-ESI/MS methods. The antimicrobial activity of compounds 1 and 2 were tested against four Gram-negative, three Gram-positive bacteria and the yeast Candida albicans by the MIC method. 相似文献
11.
Leymus chinensis (Trin.) Tzvel is a rhizomatous grass species in the Eastern Eurasian steppe zone that is often limited by low soil nitrogen availability. Although a previous study showed that the rhizomes of L. chinensis have the capacity to take up nitrogen, the importance of such uptake for nitrogen nutrition is unclear. Moreover, little is known regarding the inorganic nitrogen uptake kinetics of roots and rhizomes in response to nitrogen status. Here, we first found that ammonium is preferred over nitrate and glycine for L. chinensis growth. Using the 15N-labelling method, we found that the rate of ion influx into roots was approximately five-fold higher than into rhizomes under the same nitrogen content, and the ion influxes into roots and rhizomes under 0.05 mM N were greater than in the presence of 3 mM N, especially in the form of NH4+. Using a non-invasive micro-test technique, we characterised the patterns of NH4+ and NO3– fluxes in the root mature zone, root tip, rhizome mature zone, and rhizome tip following incubation in the solution with different N compounds and different N concentrations. These results suggest a dynamic balance between the uptake, utilisation, and excretion of nitrogen in L. chinensis. 相似文献
12.
The genus Ludwigia belongs to the Onagraceae family and it encompasses seventy-five species of aquatic plants. The chemistry of this genus is scarcely investigated, although some studies have demonstrated the potential of Ludwigia leptocarpa to produce important bioactive compounds. Herein, we describe the phytochemical investigation of Ludwigia abyssinica A. Rich. Two new steroids named 3β-formyloxy-5α,6α-dihydroxysitostane (Ludwigiaformyl A, 1) and 3β,6α-diformyloxy-5α-hydroxysitostane (Ludwigiaformyl B, 2), along with six known compounds, 3β-formyloxysitost-5-en (3), 5α,6β-dihydroxysitosterol (4), maslinic acid (5), oleanolic acid (6) and a mixture of two iridoids: linearin (7) and 1-epilinearin (8) were obtained from whole plant of L. abyssinica. The structures of the isolated compounds were established by extensive analysis of their spectroscopic and spectrometric data, which included HR-TOF-ESIMS, 1D NMR (1H, 13C) and 2D NMR (1H–1H COSY, HSQC, HMBC and ROESY) and by comparison with data reported in the literature. The antimicrobial activities of extracts, fractions, and new compounds (1) and (2) were evaluated using broth microdilution method against fungi and bacteria strains. The MeOH extract and the ethyl acetate fraction displayed different degrees of antibacterial and antifungal activities (MIC = 32 – 512 µg/mL; MMC = 64 – 512 µg/mL) whereas compounds 1 and 2 showed moderate antimicrobial activities against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Shigella flexneri and Cryptococcus neoformans (MIC = 8 – 32 µg/mL; MMC = 8 – 64 µg/mL). 相似文献
13.
The 4,4-dimethylsterols 4α-lanost-24-ene-3β,9α-diol-[2-3H2] and parkeol-[2-3H2] were synthesized from lanosterol and subsequently incubated with cultures of Ochromonas malhamensis. 5α-Lanost-24-ene-3β,9α-diol was converted into poriferasterol with three times the efficiency of parkeol. Clionasterol was also found to be labelled from both parkeol and 5α-lanost-24-ene-3β,9α-diol. No significant incorporation of radioactivity into sterols was obtained after feeding 5α-lanost-24-ene-3β,9α-diol to higher plants, the chlorophyte alga Trebouxia, yeast or a cell free homogenate of rat liver. 相似文献
14.
The main diterpenoids in the roots of Arctopus (Apiaceae, tribe Saniculeae) have been identified for the first time. The major compounds are manool, ent-trachyloban-19-oic acid and a kauren-19-oic acid, while methyl-16β-hydroxy-ent-kaur-11-en-19-oate is a minor diterpene. Comparative studies of non-polar extracts by means of LC–MS showed that the isolated main compounds are present in all three species of Arctopus. The study also revealed that the diterpenoid pattern in Arctopus is very similar to that of the genus Alepidea. The tuberous roots of Arctopus and the rhizomes and roots of Alepidea are important traditional medicines in South Africa, used mainly for infections and respiratory ailments. Their efficacy is ascribed to antimicrobial and anti-inflammatory activity. The known biological activities of the isolated diterpenes provide a scientific rationale for the traditional uses. The chemical similarity in diterpenoids also supports the idea that the two genera are closely related, despite their conspicuous morphological differences. 相似文献
15.
Obtusifoliol-[2,2,4-3H3] was synthesised and incubated with the chrysophyte alga Ochromonas malhamensis which converted it into poriferasterol. A reaction sequence applied to poriferasterol showed that the tritium retained at C-4 occupied the 4α-position. This demonstrates that biological C-4 demethylation of a 4α-methylsterol precursor by O. malhamensis results in the axial 4β-hydrogen being inverted into the equatorial 4α-position of the 4-desmethyl sterol product. 相似文献
16.
5α,6-3H2-Solacongestidine and 5α,6-3 H2-(22S)-dihydrosolacongestidine administered to Solanum dulcamara as well as 16-3H2-(22S: 25R)-22,26-epimino- cholest-5-en-3β-ol (25-isodihydroverazine) and 7α-3H-(22S: 25R)-22,26-epimino-cholest-5-en-3β,16β-diol administered to Solanum laciniatum were converted to coladulcidine and solasodine, respectively. These results are discussed in relation to spirosolane alkaloid biosynthesis. 相似文献
17.
Jyoti Srivastava 《Carbohydrate research》2010,345(14):2023-2029
Methylated anthocyanin glycosides were isolated from red Canna indica flower and identified as malvidin 3-O-(6-O-acetyl-β-d-glucopyranoside)-5-O-β-d-glucopyranoside (1), malvidin 3,5-O-β-d-diglucopyranoside (2), cyanidin-3-O-(6″-O-α-rhamnopyranosyl-β-glucopyranoside (3), cyanidin-3-O-(6″-O-α-rhamnopyranosyl)-β-galactopyranoside (4), cyanidin-3-O-β-glucopyranoside (5) and cyanidin-O-β-galactopyranoside (6) by HPLC-PDA. Their structures were subsequently determined on the basis of spectroscopic analyses, that is, 1H NMR, 13C NMR, HMQC, HMBC, ESI-MS, and UV-vis. Compounds (1-4) were found to be in major quantity while compounds (5-6) were in minor quantity. 相似文献
18.
The endophytic fungus Piriformospora indica colonizes the roots of many plant species including Arabidopsis and promotes their performance, biomass, and seed production as well as resistance against biotic and abiotic stress. Imbalances in the symbiotic interaction such as uncontrolled fungal growth result in the loss of benefits for the plants and activation of defense responses against the microbe. We exposed Arabidopsis seedlings to a dense hyphal lawn of P. indica. The seedlings continue to grow, accumulate normal amounts of chlorophyll, and the photosynthetic parameters demonstrate that they perform well. In spite of high fungal doses around the roots, the fungal material inside the roots was not significantly higher when compared with roots that live in a beneficial symbiosis with P. indica. Fifteen defense- and stress-related genes including PR2, PR3, PAL2, and ERF1 are only moderately upregulated in the roots on the fungal lawn, and the seedlings did not accumulate H2O2/radical oxygen species. However, accumulation of anthocyanin in P. indica-exposed seedlings indicates stress symptoms. Furthermore, the jasmonic acid (JA) and jasmonic acid-isoleucine (JA-Ile) levels were increased in the roots, and consequently PDF1.2 and a newly characterized gene for a 2-oxoglurate and Fe2+-dependent oxygenase were upregulated more than 7-fold on the dense fungal lawn, in a JAR1- and EIN3-dependent manner. We conclude that growth of A. thaliana seedlings on high fungal doses of P. indica has little effect on the overall performance of the plants although elevated JA and JA-Ile levels in the roots induce a mild stress or defense response. 相似文献
19.
Khushi L. Matta Surjit S. Rana Conrad F. Piskorz Joseph J. Barlow 《Carbohydrate research》1983,112(2):213-220
Reaction of 2,3,4-tri-O-acetyl-α-l-fucopyranosyl bromide with p-nitrophenyl 3,4-O-isopropylidene-β-d-fucopyranoside in the presence of mercuric cyanide in acetonitrile, followed by removal of the isopropylidene group under mild conditions, gave a mixture of p-nitrophenyl 2-O-(2,3,4-tri-O-acetyl-α- and -β-l-fucopyranosyl)-β-d-fucopyranoside. These compounds were conveniently separated by preparative, thin-layer chromatography, and, on deacetylation, gave the title disaccharides, whose structures were established by 1H- and 13C-n.m.r. spectroscopy. 相似文献
20.
Two new diterpenoids, 3β-(β-d-glucopyranosyl)isopimara-7,15-diene-11α,12α-diol (1), and 16-O-β-d-glucopyranosyl-3β-20-epoxy-3-hydroxyabieta-8,11,13-triene (2), along with three known ones were isolated from the roots of Clerodendrum bungei. These compounds were purified, and their structures were elucidated by extensive spectroscopic analyses, especially 2D NMR experiments. All compounds were evaluated for cytotoxicity against several tumor cell lines. 相似文献