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1.
A new andirobin, thaimoluccensin A (1), and two new phragmalin-type limonoids, thaimoluccensins B (2) and C (3), were isolated from seeds of a Thai mangrove plant, Xylocarpus moluccensis, together with eight known compounds. The structures of these compounds were elucidated on the basis of spectroscopic data. Only 7-deacetylgedunin (7), a gedunin-type limonoid, exhibited significant inhibitory activity against nitric oxide production from activated macrophages with IC50 value less than 10 μM, suggesting that the compound has anti-inflammatory activity.  相似文献   

2.
von Reuss SH  Wu CL  Muhle H  König WA 《Phytochemistry》2004,65(15):2277-2291
The essential oils and extracts of Mylia taylorii and M. nuda were investigated by gas chromatography, mass spectrometry, NMR spectroscopy and chemical correlations. Beside several known compounds 13 new constituents including three new carbon skeletons could be identified. Four hydrocarbons with a molecular formula of C15H22 (m/z 202) were identified as myli-4(15)-ene (1), aromadendra-1(10),4(15)-diene (19), aromadendra-4,10(14)-diene (20) and aromadendra-4,9-diene (21). Three oxaspiro-compounds were identified as 7-epi-bourbon-3-en-5,11-oxide (22), guai-3,10(14)-dien-5,11-oxide (23) and guai-3,9-dien-5,11-oxide (24). The absolute configuration of myli-4(15)-en-3-one (5) could be established by chemical correlation. Together with α-taylorione (7) the corresponding 6,11-seco-compound taylopyran (25) with a new carbon skeleton was identified which serves as a precursor to taylocyclane (26) and taylofuran (27). Taynudol (28) contains a new carbon skeleton with a cyclobutenyl structure.  相似文献   

3.
Shi-Biao Wu 《Steroids》2009,74(9):761-18673
Three new (1-3) and several known (4-6) steroids were isolated from the leaves of Chinese Melia azedarach. The structures of the new compounds were elucidated by means of spectroscopic methods including 2D NMR techniques and mass spectrometry to be (20S)-5,24(28)-ergostadiene-3β,7α,16β,20-tetrol (1), (20S)-5-ergostene-3β,7α,16β,20-tetrol (2), and 2α,3β-dihydro-5-pregnen-16-one (3). The cytotoxicities of the isolated compounds against three human cancer cell lines (A549, H460, U251) were evaluated; only compounds 1, 2, and (20S)-5-stigmastene-3β,7α,20-triol (4) were found to show significant cyctotoxic effects with IC50s from 12.0 to 30.1 μg/mL.  相似文献   

4.
The reaction of 3β-hydroxy-21-hydroxymethylidenepregn-5-en-3β-ol-20-one (1) with phenylhydrazine (2a) affords two regioisomers, 17β-(1-phenyl-3-pyrazolyl)androst-3-en-3β-ol (5a) and 17β-(1-phenyl-5-pyrazolyl)androst-5-en-3β-ol (6a). The direction of the ring-closure reactions of 1 with p-substituted phenylhydrazines (2b-e) depends strongly on the electronic features of the substituents. Oppenauer oxidation of 3β-hydroxy-17β-exo-heterocyclic steroids 5a-e and 6a-e yielded the corresponding Δ4-3-ketosteroids 9a-e and 10a-e. The inhibitory effects (IC50) of these compounds on rat testicular C17,20-lyase were investigated by means of an in vitro radioligand incubation technique.  相似文献   

5.
Two new spirostanoides, filiasparosides E (1) and F (2), one new furostanoside, filiasparoside G (3), and one new ecdysterone, stachysterone A-20, 22-acetonide (4), together with six known steroidal saponins, asparagusin A (5), filiasparoside A (6), filiasparoside B (7), aspafilioside A (8), aspafilioside B (9), and filiasparoside C (10) were isolated from the roots of Asparagus filicinus Buch.-Ham. Their structures were elucidated on the basis of spectroscopic and chemical evidence. Compounds 1-10 were investigated for their cytotoxicities against human breast adenocarcinoma MDA-MB-231 cell line and compounds 8-10 exhibited cytotoxic activities with IC50 values ranging from 3.4 to 6.6 μM.  相似文献   

6.
Two new diterpenes, lobocompactols A (1) and B (2), and five known compounds (3-7) were isolated from the methanol extract of the soft coral Lobophytum compactum using combined chromatographic methods and identified based on NMR and MS data. Each compound was evaluated for cytotoxic activity against A549 (lung) and HL-60 (acute promyelocytic leukemia) human cancer cell lines. Among them, compound 5 exhibited strong cytotoxic activity against the A549 cell line with an IC50 of 4.97 ± 0.06 μM. Compounds 3, 4, and 7 showed moderate activity with IC50 values of 23.03 ± 0.76, 31.13 ± 0.08, and 36.45 ± 0.01 μM, respectively. The cytotoxicity of 5 on the A549 cells was comparable to that of the positive control, mitoxantrone (MX). All compounds exhibited moderate cytotoxicity against the HL-60 cell line, with IC50 values ranging from 17.80 ± 1.43 to 59.06 ± 2.31 μM. Their antioxidant activity was also measured using oxygen radical absorbance capacity method, compounds 1 and 2 exhibiting moderate peroxyl radical scavenging activity of 1.4 and 1.3 μM Trolox equivalents, respectively, at a concentration of 5 μM.  相似文献   

7.
The crystalline compounds [LnCl2(L)(thf)2] [Ln = Ce (1), Tb (2), Yb (3)], [NdI2(L)(thf)2] (4), [LnCl(L′)2] [Ln = Tb (5), Yb (6) (a known compound)] and [YbCl(L′′)(μ-Cl)2Li(OEt2)2] (7) have been prepared [L = {N(C6H3Pri2-2,6)C(H)}2CPh, L′ = {N(SiMe3)C(Ph)}2CH, L′′ = {N(SiMe3)C(C6H4Ph-4)}2CH]. The X-ray molecular structures of 2-7 have been established; in each, the monoanionic ligand L, L′ or L′′ is N,N′-chelating and essentially π-delocalised. Each of 1-7 was prepared from the appropriate LnCl3, or for 4 [NdI3(thf)2], and an equivalent portion of the appropriate alkali metal [Li for 7, Na for 2, 3 and 5, or K for 1, 4 and 6] β-diiminate in thf; the isolation of exclusively 5 and 6 (rather than the L′ analogues of 2 or 3) is noteworthy, as is the structure of 7 which has no precedent in Group 3 or 4f metal β-diiminato chemistry.  相似文献   

8.
From the reaction of tert-butyl lithium or n-butyl lithium with N-methylpyrrole (1a), furan (1b) or 2-bromo-thiophen (1c), 2-N-methylpyrrolyl lithium (2a), 2-furyl lithium (2b) or 2-thiophenyl lithium (2c), respectively, was obtained. When reacted with 6-(2-N-methylpyrrolyl) fulvene (3a), 6-(2-furyl) fulvene (3b) or 6-(2-thiophenyl) fulvene (3c), the corresponding lithiated intermediates were formed (4a-c). Titanocenes (5a-c) were obtained through transmetallation with titanium tetrachloride. When these titanocenes were tested against pig kidney epithelial (LLC-PK) cells, inhibitory concentrations (IC50) of 32 μM, 140 μM, and 240 μM, respectively, were observed. These values represent improved cytotoxicity against LLC-PK, compared to their ansa-analogues.  相似文献   

9.
Seven new withanolides (1-7), along with three known ones (8-10), were isolated from the leaves of Withania aristata. Their structures were elucidated on the basis of spectroscopic analysis, including 2D NMR experiments and spectrometric techniques, and the absolute configuration of 1 and 2 was established by CD analysis. In the search for new cytotoxic compounds from Withania species, the isolated compounds 1-9, along with two derivatives, were assayed for their cytotoxicity against HeLa, MCF-7 and A-549 human tumor cell lines. Derivative (4S,20R,22R)-27-acetoxy-4-p-bromobenzoyloxy-1-oxo-witha-2,5,16,24-tetraenolide (13) showed cytotoxicity against all the cell lines assayed with IC50 values ranging from 2.8 to 3.6 μM, and (4S,20R,22R)-4,27-diacetoxy-4-hydroxy-1-oxo-witha-2,5,16,24-tetraenolide (12) exhibited an IC50 value of 5.4 μM on the MCF-7 cell line.  相似文献   

10.
Investigation of the MeOH extract obtained from the root of the Ziziphus mauritiana grown in Thailand resulted in the isolation of two 14- and 13-membered cyclic alkaloids, mauritine L (1) and mauritine M (2), and three known cyclopeptide alkaloids, nummularines H (3), B (4) and hemsine A (5). Their structures were elucidated on the basis of extensive NMR spectroscopic analysis. The first single crystal X-ray diffraction study of the 13-membered ring cyclopeptide, nummularine B methiodide (4′), revealed all S configurations on the amino acid residues. The isolated alkaloids exhibited potent antiplasmodial activity against the parasite Plasmodium falciparum with the inhibitory concentration (IC50) ranging from 3.7 to 10.3 μM. Compounds 2 and 3 also demonstrated antimycobacterial activity against Mycobacterium tuberculosis with the MIC of 72.8 and 4.5 μM, respectively.  相似文献   

11.
The lithium β-diketiminate (1c, [Li{N(2,6-iPr2C6H3)C(Ph)CHC(tBu)NH}]2 represented as (LiL)2) reacted with 3d-metal (II) chlorides to afford the corresponding compounds (2-7). All metal compounds were fully characterized by elemental, spectroscopic analyses and the single-crystal X-ray diffraction. The coordination geometries around the metals are shown to be tetrahedral within the trinuclear Co2Li compound (2), planar in ML2 (M = Co, 3), pseudo-tetrahedral conformation in the ML2 with M as Mn (4), Fe (5) or Zn (6), and square planar in the dinickel compound (7). Indicated by the trimetallic Co2Li compound 2, a six-membered ring is constructed of three metal atoms and three bridged chlorides as a twisted conformation. An inversion center is present in the centroid of the Ni2Cl2 four-membered ring within compound 7. The plausible mechanism of forming ML2 was proposed through the chloro-bridged multinuclear compounds on the basis of isolated intermediates of trinuclear (2) and dinuclearic (7) compounds. Upon treatment with methylaluminoxane (MAO), the nickel compound 7 possessed good activity towards ethylene oligomerization, whereas the other metal compounds showed moderate activities towards ethylene polymerization.  相似文献   

12.
Nine oxygenated cyclohexanoids, speciosins L-T (1-9) as well as a 5H-furan-2-one metabolite, 5′-O-acetylaporpinone A (10), together with known analogs, speciosins A, B, D, E, F, I and K (11-17), and aporpinone A (18), were isolated from a scale-up cultures of the basidiomycete Hexagonia speciosa. Their structures were elucidated by analysis of spectroscopic data, including 1D and 2D NMR. Speciosin B (12) showed significant cytotoxicity against several tumor cell lines with IC50 values in the range 0.23-3.30 μM.  相似文献   

13.
A series of dihydropyrimidin-(2H)-one analogues and rhodanine derivatives were synthesized and their inhibitory effects on the diphenolase activity of mushroom tyrosinase were evaluated. The results showed that some of the synthesized compounds exhibited significant inhibitory activities. Especially, compound 15 bearing a hydroxyethoxyl group at position-4 of phenyl ring exhibited most potent tyrosinase inhibitory activity with IC50 value of 0.56 mM. The inhibition mechanism analysis of compound 15 demonstrated that the inhibitory effect of the compound on the tyrosinase was irreversible. These results suggested that such compounds might be served as lead compounds for further designing new potential tyrosinase inhibitors.  相似文献   

14.
Two new monoterpene glycosides, distyloside A-B (1-2), and a new megastigmane glucoside, iso-dihydrodendranthemoside A (3) were isolated from twigs and leaves of Distylium racemosum, along with five known phenolic compounds (4-8). The structures were established via spectroscopic techniques and chemical transformations, and the absolute stereochemistry of 3 was determined by Mosher’s esterification. A homogeneous fluorescence resonance energy transfer (FRET) quenching assay was used to determine the inhibitory activity of isolates (1-8) on the ribonuclease H enzymes from HIV-1, 2, human, and Escherichia coli. Among them, 6″-O-galloylsalidroside (6) showed potent inhibitory effects with an IC50 value of 3.5 μM on HIV-2, and 1.7 μM on human RNase H, respectively.  相似文献   

15.
Hyper-pigmentation of the skin is a common problem that is prevalent in middle aged and elderly people. It is caused by over production of melanin. Tyrosinase is known to be the key enzyme in melanin production. Ethanolic extract of Greyia flanaganii leaves showed significant (P < 0.05) antityrosinase activity exhibiting the IC50 of 32.62 μg/ml. The total extract was further investigated for its toxicity and effect on melanin production by melanocytes cells, and showed significant inhibition (P < 0.05) (20%) of melanin production at 6.25 μg/ml and low levels of cytotoxicity (IC50 < 400 μg/ml). The amount of antioxidants necessary to decrease the initial DPPH absorbance by 50% (EC50) by the total ethanolic extract was found to be 22.01 μg/ml. The effect of G. flanaganii against acne causing bacteria, Propionibacterium acnes, was investigated using microdilution assay. The MIC of the extract of G. flanaganii was found to be 250 μg/ml. Bioassay-guided fractionation led to the isolation of (3S)-4-hydroxyphenethyl 3-hydroxy-5-phenylpentanoate (1), 2′,4′,6′-trihydroxydihydrochalcone (2), 2′,6′,4-trihydroxy-4′-methoxydihydrochalcone (3), 2′,6′-dihydroxy-4′-methoxydihydrochalcone (4), 5,7-dihydroxyflavanone [(2S)-pinocembrin] (5), 2′,6′-dihydroxy-4′,4-dimethoxy dihydrochalcone (6) and (2R,3R)-3,5,7-trihydroxy-3-O-acetylflavanone (7). The isolated compounds were tested for their antioxidant, cytotoxicity, tyrosinase inhibition and antibacterial activities. Compound 2 exhibited significant (P < 0.05) antityrosinase activity exhibiting the IC50 of 69.15 μM. The isolated compounds showed low toxicity of the cells with reduction of melanin content of the cells. All compounds tested showed good radical scavenging activity. These data indicates that G. flanaganii extract and its isolated phenolic constituents could be possible skin lightening agents.  相似文献   

16.
Three new dammarane-type sapogenins (1, 3, and 5) together with two known ones (2 and 4) were isolated from the total hydrolyzed saponins extracted from Panax ginseng berry. Their structures were elucidated using a combination of 1D and 2D 1H and 13C NMR spectra and mass spectroscopy as 20(R)-25-methoxyl-dammarane-3β,12β,20-triol (1), 20(R)-25-methoxyl-dammarane-3β,6α,12β,20-tetrol (2), 20(R)-20-methoxyl-dammarane-3β,12β,25-triol (3), 20(R)-20,25-dimethoxyl-dammarane-3β,12β-diol (4), and (12R,20S,24S)-20,24-; 12,24-diepoxy-dammarane-3β-ol (5). Their antitumor activities were evaluated in six human cancer cell lines. The novel compounds 1 and 3 showed significant cytotoxic activity against the six cell lines. The IC50 values of 3 against HepG2, Colon205, and HL-60 were the lowest (8.78, 8.64, and 3.98 μM, respectively). Compounds 1 and 20(S)-25-OCH3-PPD, which are a pair of configuration isomers, showed a 10- to 100-fold greater growth inhibition than ginsenoside-Rg3 (an anti-cancer clinical agent in China). The data presented here may be useful for the development of novel anti-cancer agents.  相似文献   

17.
The present study reports the isolation of sixteen lignans (1–16), an aporphine alkaloid (17), two phenolic amides (18 and 19), and a germacrane sesquiterpene lactone (20) from T. odorum. Except for compound 20, the other isolated constituents are firstly reported from T. odorum. And in this study, three polylignans (11–13) and six norlignans (5–7, 14–16) are reported for the first time from the Magnoliaceae family, which may support the opinion to establish Tsoongiodendron as a monotypic genus from a chemotaxonomical point of view.  相似文献   

18.
A series of dibenzylideneacetones (A1-A12) and some of their pyrazolines (B1-B4) were synthesized and evaluated in vitro for blood stage antiplasmodial properties in Plasmodium falciparum culture using SYBR-green-I fluorescence assay. The compound (1E, 4E)-1,5-bis(3,4-dimethoxyphenyl)penta-1,4-dien-3-one (A9) was found to be the most active with IC50 of 1.97 μM against chloroquine-sensitive strain (3D7) and 1.69 μM against chloroquine-resistant field isolate (RKL9). The MTT based cytotoxicity assay on HeLa cell line has confirmed that A9 is selective in its action against malaria parasite (with a therapeutic index of 166). Our results revealed that these compounds exhibited promising antiplasmodial activities which can be further explored as potential leads for the development of cheaper, safe, effective and potent drugs against chloroquine-resistant malarial parasites.  相似文献   

19.
Yu BZ  Zhang GH  Du ZZ  Zheng YT  Xu JC  Luo XD 《Phytochemistry》2008,69(13):2523-2526
Four azaphilones, named phomoeuphorbins A-D (1-4) were isolated from cultures of Phomopsis euphorbiae, an endophytic fungus isolated from Trewia nudiflora. Structures of 1-4 were established on the basis of spectroscopic analyses, including application of 2D NMR spectroscopic techniques. Phomoeuphorbins A and C exhibited very weak inhibitory activities against HIV replication in C8166 cells in vitro.  相似文献   

20.
Six new bufadienolides (1-6) and two new C23 steroids (7 and 8), together with three known compounds (9-11) were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated by spectroscopic analysis and single-crystal X-ray diffraction. In vitro cytotoxicities of all compounds were evaluated in A549 cancer cell line. Compounds 2, 3 and 10 showed significant cytotoxic activities.  相似文献   

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