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1.
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2.
Six sesquiterpenes: germacrone (1), zederone (2), dehydrocurdione (3), curcumenol (4), zedoarondiol (5) and isocurcumenol (6) were isolated from rhizomes of Curcuma aeruginosa Roxb. (Zingiberaceae). They inhibited 5α-reductase which converts testosterone to dihydrotestosterone (DHT). Germacrone (1) was the most potent (IC(50)=0.42±0.05 mg/mL). Compound 1 was anti-androgenic in LNCaP cells when proliferation was testosterone-induced. The growth of flank gland of male Syrian hamsters is dependent on circulating androgen and when maintained with testosterone, 1 (3, 30, 100μg) inhibited growth but was ineffective against DHT. The similar activity profile was observed on the 5α-reductase inhibitor, finasteride (100 μg) treatment group. The androgen receptor binding assay showed that 1 did not bind to the androgen receptor. In conclusion, 1 showed anti-androgenic effect on in vitro and in vivo assays. One of the possible mechanisms was inhibition 5α-reductase activity. Thus, 1 is a potential lead compound for treatment of androgen-dependent disorders.  相似文献   

3.
Zhang JL  Tian HY  Li J  Jin L  Luo C  Ye WC  Jiang RW 《Fitoterapia》2012,83(5):973-978
A new diketosteroid, (E)-stigmasta-24(28)-en-3,6-dione (1), along with three known steroids (2-4) was isolated from marine alga Tydemania expeditionis collected in China Sea. Their structures were elucidated by extensive spectroscopic methods. Comparison of the chemical constituents revealed significant diversity among different locations. The biological activities of 1, 3 and 4 were evaluated on the prostate cancer cell lines and androgen receptor. Compound 1 exhibited moderate inhibitory activities against the prostate cancer cells DU145, PC3 and LNCaP with IC(50) values of 31.27±1.50, 40.59±3.10 and 19.80±3.84 μM, respectively. Compound 3 showed more potent activities with IC(50) values of 12.38±2.47, 2.14±0.33 and 1.38±0.07 μM, respectively. However, compound 4 showed only weak inhibitory activities on LNCaP cells and was inactive on DU145 and PC3 cells. A competitive binding assay showed that compound 1 exhibited significant affinity to the androgen receptor with an IC(50) value of 7.19±0.45 μM, while 3 and 4 were inactive. The fact that the inhibitory properties of 1 and 3 against the prostate cancer cells were inconsistent with their affinities to the androgen receptor suggested that there might be other mechanism of action involved in the cytotoxic activity.  相似文献   

4.
A series of cardiac glycosides were isolated and identified from the anti-tumor fraction of the root of Streptocaulon juventas in previous studies. In the present research, the cytotoxic activities of the 43 cardiac glycosides on three cell lines, human lung A549 adenocarcinoma cell, large cell lung cancer NCI-H460 cell and normal human fetal lung fibroblast MRC-5 cell, were evaluated in vitro. Most of the tested compounds showed potent inhibitory activities toward the three cell lines. Then, the structure–activity relationships were discussed in detail. It was indicated that hydroxyl and acetyl groups at C-16 increased the activity, whereas hydroxyl group at C-1 and C-5 can both increase and decrease the activity. Two glucosyl groups which were connected by C1′ → C6′ showed better inhibitory activity against cancer cell lines, while the C1′ → C4′ connection showed stronger inhibitory activity against the normal cell line. Also, this is the first report that the activities of these compounds exhibited different variation trends between A549 and NCI-H460 cell lines, which indicated that these compounds could selectively inhibit the cell growth. The results would lay a foundation for further research on new anti-tumor drug development.  相似文献   

5.
To examine the effect of the presence of benzylic hydroxyl group on the reaction of β-O-4 type lignin moiety with active oxygen species (AOS) under oxygen bleaching conditions, a specially designed β-O-4 type model compound carrying the benzylic methoxyl group, 2-(3,5-difluorophenoxy)-3-methoxy-3-(3,4-dimethoxyphenyl)propan-1-ol (IV), was treated together with a phenolic compound, 4-hydroxy-3-methoxybenzyl alcohol (II), under oxygen bleaching conditions. In this reaction system, AOS were generated by reactions of compound II with dioxygen and attacked compound IV. Compound IV was rather stable, while an analogous model compound carrying the benzylic hydroxyl group, 2-(3,5-difluorophenoxy)-1-(3,4-dimethoxyphenyl)propane-1,3-diol (I), was rather degraded. This result and the previous knowledge on the relatively high stability of 3,4-dimethoxybenzyl alcohol carrying only the hydroxymethyl group as side-chain under the identical reaction conditions suggested that the existence of benzylic hydroxymethylene group is essential in the extensive reaction of side-chain of β-O-4 type lignin moiety with AOS. To compare the reactivity of AOS toward different types of hydroxyl and aryloxyl carbons, 2-(3,5-difluorophenoxy)propane-1,3-diol (VI) or 3-(3,5-difluorophenoxy)propane-1,2-diol (VII) was also subjected to this reaction system. Compound VII was degraded by AOS more extensively than compound VI.  相似文献   

6.
The rates (k) of hydroxymethylation of phenol, resorcinol, phloroglucinol, and several methylphenols in diluted 10% dimethylformamide aqueous alkaline solution were calculated based on the consumption of phenols and formaldehyde. Thek values of phloroglucinol and resorcinol relative to that of phenol were about 62000 and 1200 times, respectively. The phenols that have methyl or hydroxyl groups at the C-3 or C-5 position (or both) have larger rate constants than phenols with substituents at other positions. Several kinds of atomic charge of the carbons on the aromatic ring of phenols were calculated using the semiempirical orab initio method. The correlations between the averagek (Ave.k) and average electrostatic charges (Ave.q) at the carbons were fairly good. Highest occupied molecular orbitals (HOMO) were observed. The best correlation between Ave.k and Ave.q was obtained when diphenols and triphenols were assumed to exist in solution as their respective di-anion.  相似文献   

7.
The consumption rates of three monolignols (p-coumaryl, coniferyl, and sinapyl alcohols) and eight analogues using horseradish peroxidase (HRP)–H2O2 as an oxidant were measured and compared with the anodic peak potentials thereof measured with cyclic voltammetry. 3-Monosubstituted p-coumaryl alcohols, i.e., 3-methoxy-, 3-ethoxy-, 3-n-propoxy-, and 3-n-butoxy-p-coumaryl alcohols, had faster reaction rates than p-coumaryl alcohol. This is most probably due to the electron-donating effect of alkoxyl groups. However, the reaction rates gradually decreased with an increase in the molecular weight of the alkoxyl groups. Furthermore, t-butoxyl group, which is a very bulky substituent, caused an extreme reduction in the reaction rate, even though its electron-donating effect was almost the same as that of other alkoxyl groups. The reaction rates of 3,5-disubstituted p-coumaryl alcohols, especially 3,5-dimethyl-p-coumaryl alcohol, were very low compared with 3-monosubstituted p-coumaryl alcohols. These results suggest that there are three main factors of hindrance during the approach of monolignols to the active site of HRP. First, from the results of 3-monoalkoxy-p-coumaryl alcohols, it was suggested that the volume of substituents could decrease their oxidation rates. Second, from the results of 3,5-disubstituted p-coumaryl alcohols, it was suggested that local steric hindrance by the amino residues quite near the heme decreased the oxidation rates. Third, from the results of the substrates with hydrophobic substituents at their 3,5-positions, we suggested that hydrophilicity near heme would decrease their oxidation rates.  相似文献   

8.
Prostate cancer is the fifth most common neoplasm worldwide, and the second most common cancer among men. Ginsenosides, the main component of ginseng, have been known for their medicinal effects such as anti-inflammatory and anti-proliferative activities. In this study, we investigated the inhibitory effects of ginsenosides (ginsenoside 20(R)-Rh2 and ginsenoside 20(S)-Rh2) on prostate cancer cells in vitro. Only ginsenoside 20(S)-Rh2 showed proliferation inhibition on androgen-dependent and -independent prostate cancer cells. These results implied that the stereochemistry of the hydroxyl group at C-20 may play an important role in antitumor activities.  相似文献   

9.
A water-soluble polysaccharide LT1 was isolated from the basidiocarps of Lentinus edodes by hot water extraction and ethanol precipitations, further purified by gel chromatography. The Mw of LT1 was estimated to be 642 kDa by using HPGPC. Chemical and spectroscopic studies illustrated that LT1 has a backbone chain composed of 1 → 4-linked and 1 → 3-linked glucopyranosyl residues and has branches of single glucosyl stubs at C-6 of β-(1 → 4)-linked glucopyranosyl. AFM and Congo-red test revealed that LT1 existed as triple helix chain in 0.10 M NaOH solution or distilled water. Our studies showed that LT1 presented significant antitumor bioactivities on Sarcoma180 solid tumor cell implanted in BALB/c mice, which implies that LT1 could be potentially applied as a natural antitumor drug.  相似文献   

10.
Six new anthraquinone glycosides: digiferruginol-1-methylether-11-O-β-gentiobioside (1); digiferruginol-11-O-β-primeveroside (2); damnacanthol-11-O-β-primeveroside (3); 1-methoxy-2-primeverosyloxymethyl-anthraquinone-3-olate (4); 1-hydroxy-2-primeverosyloxymethyl-anthraquinone-3-olate (5); and 1-hydroxy-5,6-dimethoxy-2-methyl-7-primeverosyloxyanthraquinone (6) were isolated from Morinda citrifolia (Rubiaceae) roots together with four known anthraquinone glycosides. The structures of the new compounds were established using spectral methods. For five of the new compounds, the sugar is attached via the hydroxymethyl group of the anthraquinone C-2 carbon. This type of bond is rarely found for anthraquinone glycosides isolated from natural sources.  相似文献   

11.
To examine why green liquor (GL) pretreatment of lignocellulosic materials effectively facilitates enzymatic saccharification under conditions milder than those of a common alkaline cooking process, dimeric β-O-4 type lignin model compounds with and without free phenolic hydroxyl group were reacted in several alkaline solutions including a model solution of GL, which mainly contains Na2CO3 and Na2S. The β-O-4 bond of the phenolic model compound was cleaved with a sufficient rate in the model solution of GL. The β-O-4 bond cleavage of the non-phenolic model compound was more frequent in the model solution of GL than in other alkaline solutions. These results suggest that β-O-4 bonds present in lignocellulosic materials are effectively cleaved in a GL pretreatment. It was also suggested that HS? and CO3 2? synergistically contribute to the β-O-4 bond cleavage of the non-phenolic model compound under GL pretreatment conditions.  相似文献   

12.
Antifeedant activity of some flavonoids and their related compounds against the subterranean termiteCoptotermes formosanus Shiraki was examined with nochoice tests and two-choice tests. The activities of these compounds were evaluated in relation to their chemical structures. All flavonoids tested showed antifeedant activity, whereas catechinic acid, possessing no A-ring or pyran ring in the molecule, showed feeding-preference activity. For the structure-activity relations, it was found that compounds containing two hydroxyl groups at C-5 and C-7 in A-rings showed high antifeedant activity. Furthermore, the presence of a carbonyl group at C-4 in the pyran rings of the compounds was necessary for the occurrence of high activity. 3-Hydroxyflavones and 3-hydroxyflavanones with 3,4-dihydroxylated B-rings exhibited higher activity than those with 4-hydroxylated B-rings.Part of this paper was presented at the 49th annual meeting of the Japan Wood Research Society, Tokyo, April 1999  相似文献   

13.
The work presented here is the first study performed on the biotransformation and/or metabolism of atractylenolide I (1) as a valuable anti-inflammatory and chemopreventive agent, using liver microsomes from rats pre-treated with sodium phenobarbital. Two known eudesmane-type sesquiterpenoid lactones, namely 1β-acetoxyatractylenolide I (2) and 1β-hydroxy-atractylenolide I (3), and five new ones, namely 3β-hydroxy-atractylenolide I (4), 1β,13-dihydroxy-atractylenolide I (5), 1β,2α-dihydroxy-atractylenolide I (6), 1β,3α-dihydroxy-atractylenolide I (7), and 1β,3β-dihydroxy-atractylenolide I (8) were obtained. Their chemical structures were unambiguously established by both 1D and 2D NMR as well as mass spectroscopic techniques. The result indicated that the parent prototype compound 1 could be specifically oxidized at C-1, C-2 and C-3 of A-ring, suggesting that the oxidizable of 1 may contribute to its in vivo anti-inflammatory and chemopreventive effects. And the result also provided valuable information for further investigation of relationship among metabolic activation and liver microsomal cytochrome P450 enzyme isoforms.  相似文献   

14.
A series of novel 4-O-alkoxytrityl chlorides (1) with different chain lengths was synthesized as a novel reagent for obtaining 6-O-alkylated cellulose with high regioselectivity via trityl groups in one reaction step without the use of any protective groups. These chlorides were reacted with methyl -d-glucoside, which was used as a model compound, to examine the reactivities toward the primary hydroxyl groups of cellulose to afford a series of 6-O-alkylated methyl -d-glucosides in high yields. The product compounds were found to have interesting solubilities and thermal properties. Thus, newly prepared trityl chloride derivatives were found to be useful regioselective derivatization reagents on the primary hydroxyl group in carbohydrates, especially in cellulose.  相似文献   

15.
In this study, 4 new triterpenoids—3β- acetoxy-olean-11-en,28,13β-olide (1), 3β- acetoxy-11α,12α-epoxy-olean-28,13β-olide (2), 19α-epi-betulin (3), and 20, 28-epoxy-17β,19β-lupan-3β-ol (4)—and 12 known compounds, were isolated from the root bark of Hibiscus syriacus L. by using acetone extraction. Their structures were characterized by extensive spectroscopic analysis. To investigate cytotoxicity, A549 human lung cancer cells were exposed to the extract and the compounds identified from it. Significantly reduced cell viability was observed with betulin-3-caffeate (12) (IC50, 4.3 μM). The results of this study indicate that betulin-3-caffeate (12) identified from H. syriacus L. may warrant further investigation for potential as anticancer therapies.  相似文献   

16.
Termiticidal activity of wood vinegar, its components and their homologues   总被引：5，自引：0，他引：5  
The termiticidal activity of wood vinegar, its components, and their homologues have been studied. Three kinds of wood vinegar made from the mixed chips ofCryptomeria japonlca andPseudotsga menziesii (wood vinegar A),Quercus serrata (wood vinegar B), andPinus densiflora (wood vinegar C) exhibited high termiticidal activities againstReticulitermes speratus. Acetic acid, which is the largest content of wood vinegar, exhibited high termiticidal acitivity. The contents of organic fraction of wood vinegars and acetic acid might be responsible for the differences in termiticidal activities among these wood vinegars. The structure and termiticidal activity relations of phenols were studied. Phenol with some substituents revealed higher termiticidal activity than benzene derivatives, which have no hydroxyl group; an ortho substituent of phenol plays an important role in termiticidal activity. It has become apparent that high termiticidal activity cannot be obtained by a phenolic hydroxyl group alone; it can be obtained, however, by some substituents, especially an ortho substituent in addition to a phenolic hydroxyl group. The bulkiness of the substituent at the ortho position participates in termiticidal activity; activity decreases as the size of an ortho substituent increases. It is thought that the interaction at the receptor site of termites is affected by the increased size of the ortho substituent.  相似文献   

17.
A comprehensive investigation into the effect of molecular size of the substituent group of softwood modified with linear chain carboxylic acid anhydrides, namely acetic, propionic, butyric, valeric, hexanoic, upon the sorption of water vapour has been performed. The sorption isotherms for untreated and chemically modified wood were analysed using the Hailwood–Horrobin model. The experimental analysis of the sorption isotherms showed that esterification affects the total, polymolecular and monomolecular sorption. The effect of molecular size of the substituent group on site accessibility was addressed by comparing the effect on water vapour sorption produced by adducts with differences in molecular size. Similar levels of cell-wall bulking were produced at different levels of hydroxyl substitution. Analysis of the sorption isotherms at comparable weight percentage gain revealed that the five anhydrides used show similar effectiveness in both total, polymolecular and monomolecular sorption, despite the substantial difference in the proportion of hydroxyl groups reacted. It is concluded that the reduction in total, polymolecular and monomolecular sorption produced by the linear chain anhydrides is primarily determined by the volume of adduct deposited in the cell wall (bulking) rather than by the number of hydroxyl groups that have been substituted. The validity of the Hailwood–Horrobin model is questioned.  相似文献   

18.
Wang F  Guan Y 《Fitoterapia》2012,83(1):13-17
Four new nor-dammarane triterpenoids, 12β-O-acetyl-15α,28-dihydoxy-17β-methoxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanran (1), 12β-O-acetyl-15α,17β,28-trihydoxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanran (2), 12β-O-acetyl-15α,28-dihydoxy-3-oxo-17-en-20,21,22-23,24,25,26,27-octanordammanran (3), and 12β,15α,17β,28-tetrahydoxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanran (4), were isolated from the 70% EtOH extract of Dysoxylum hainanense. The structures of the new compounds were elucidated by spectral methods. All the triterpenoids were in vitro evaluated for their cytotoxic activities against four tumor cell lines (A549, SK-OV-3, SKMEL-2 and HCT15).  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.
Ganoderic acid Df, a new lanostane-type triterpenoid, was isolated from the fruiting body of Ganoderma lucidum. Its structure was characterized as 7β, 11β-dihydroxy-3, 15, 23-trioxo-5α-lanosta-8-en-26-oic acid by 1D- and 2D-NMR spectra. This compound exhibited potent human aldose reductase inhibitory activity, with an IC50 of 22.8 μM in vitro. A carboxyl group of this compound's side chain is essential for eliciting inhibitory activity because its methyl ester is much less active.  相似文献   

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