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1.
Four new triterpene glycosides, cucumariosides A(2)-5 (1), A(3)-2 (2), A(3)-3 (3), and isokoreoside A (4), along with the previously isolated koreoside A (5), have been found in the sea cucumber Cucumariaconicospermium. Glycoside 1 was isolated as a native substance, while glycosides 2-5 were identified through their desulfated derivatives. Their structures have been deduced by extensive spectral analysis (NMR and MS) and chemical evidence. All the glycosides contain the same branched pentasaccharide carbohydrate chain but differ in the number and positions of the sulfate groups. Glycoside 1 has one, glycosides 2 and 3 have two, and glycosides 4 and 5 have three sulfate groups. Glycosides 2-5 are non-holostane derivatives; their aglycons lack the 18(20)-lactone and are characterized by shortened side chains, which is a very rare feature among the sea cucumber glycosides.  相似文献   

2.
The mixture of flavonolignans [Legalon: silybin (2a), isosilybin (3), silydianin (4) and silychristin (5)] and derivatives of silybin (2b-d) were assessed for their inhibitory activity on the oxidative burst of PMA-stimulated human PMNLs. The inhibitory effect of flavonolignans on O(2)(-) release were compared with that of vitamin E (1). The flavonolignans tested exhibited the following order in inhibition of O(2)(-) release by PMA-stimulated PMNLs: 5,7,4"- trimethylsilybin (2c) approximately vitamin E (1) > Legalon >or= peracetylsilybin (2b) > silybin (2a) > peracetyl-5,7,4"-trimethylsilybin (2d). The flavonolignans inhibited not only the O(2)(-) release, but also the H(2)O(2) formation in PMA-stimulated PMNLs. The inhibitory capacity of flavonolignans on H(2)O(2) formation was similar to their inhibitory capacity on O(2)(-) release. These data suggest that the flavonolignans have antioxidant properties on the PMNL oxidative burst. The fact that the trimethyl derivative of silybin (2c) has a greater inhibitory effect than silybin itself suggests that the efficacy of the antioxidant properties is dependent on the lipophilicity of the molecules. This is underlined by the fact that peracetylation of all of the hydroxyl groups in silybin resulted in a total loss of the antioxidant activity of the molecule. In summary, flavonolignans inhibit the oxidative burst of PMNLs, and this inhibitory effect depends on the chemical structure of the flavonolignans.  相似文献   

3.
Four new iridoid glycosides were isolated from a 90% MeOH extract of Scrophularia buergeriana roots and characterized as 8-O-E-p-methoxycinnamoylharpagide (1), 8-O-Z-p-methoxycinnamoylharpagide (2), 6'-O-E-p-methoxycinnamoylharpagide (3), and 6'-O-Z-p-methoxycinnamoylharpagide (4), respectively. In addition, three known iridoids were identified as E-harpagoside (5), Z-harpagoside (6), and harpagide (7). Compounds 1-7 significantly attenuated glutamate-induced neurotoxicity when added to primary cultures of rat cortical cells at concentrations ranging from 100 nM to 10 microM. The results obtained indicate that the iridoid glycosides isolated from S. buergeriana have significant protective effects against glutamate-induced neurodegeneration in primary cultures of rat cortical neurons.  相似文献   

4.
Neuroprotective constituents from Hedyotis diffusa   总被引:10,自引:0,他引:10  
In a bioassay-guided search for neuroprotective compounds from medicinal plants, a MeOH extract of whole plants of Hedoytis diffusa yielded five flavonol glycosides, kaempferol 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-galactopyranoside (1), quercetin 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-galactopyranoside (2), quercetin 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-glucopyranoside (3), kaempferol 3-O-(2-O-beta-D-glucopyranosyl)-beta-D-galactopyranoside (4), and quercetin 3-O-(2-O-beta-D-glucopyranosyl)-beta-D-galactopyranoside (5), and four O-acylated iridoid glycosides (6-9). Compounds 1 and 2 are previously unreported natural products, and all nine compounds exhibited significant neuroprotective activity in primary cultures of rat cortical cells damaged by L-glutamate.  相似文献   

5.
Bioassay-guided fractionation of the MeOH extract from the octocoral Muricea austera collected in the Pacific coast of Panama led to the isolation of eight compounds, including three tyramine derivatives (1-3), two steroidal pregnane glycosides (4, 5), and three sesquiterpenoids (6-8). Compounds 2-5 are new natural products, and their structures were determined on the basis of their spectroscopic data (HRMS, 1D and 2D NMR, and CD studies). The antiprotozoal activities of the natural compounds 1-8 as well as those of a series of synthetic glycosides (11-22) and tyramine derivatives (23-35) were evaluated in vitro against a drug-resistant Plasmodium falciparum and intracellular form of Trypanosoma cruzi.  相似文献   

6.
Silymarin, an extract of Silybum marianum seeds, and the constituent flavonolignans silybin, silydianin and silychristin, as well as the flavonol quercetin, protected rat heart microsomes and mitochondria against iron-dependent doxorubicin induced lipid peroxidation. Quercetin was found to be more potent than either silymarin or its three constituents, whose cytoprotectivity was comparable. The radical scavenging activity of the compounds was investigated using a DPPH colour reduction assay and cyclic voltametry to assess their antioxidant activities. In contrast to quercetin, silybin, silydianin and silychristin did not chelate iron in aqueous solution. The results suggest that silymarin may prevent doxorubicin-mediated damage to rat heart membrane primarily through a free radical scavenging mechanism.  相似文献   

7.
Of the three flavanolignans that are found in silymarin (Silybum marianum [L.] Gaertn.), silybin is thought to be the primary therapeutic constituent. To test the capacity of silybin to protect the rat fetus from toxic effects of maternally ingested EtOH we did the following: Adult female rats were assigned to one of four groups; EtOH, EtOH/silybin, pair-fed control, and chow fed control. Silybin was orally administered as Siliphos(R), which is one part silybin to two parts phosphatidylcholine. All groups except the chow-fed control were maintained on a liquid diet throughout pregnancy. On day 21 of pregnancy the rats were killed and the fetuses removed. Gamma glutamyl transpeptidase (GGTP) activity and glutathione (GSH) levels were determined for liver and brain tissue for both the fetuses and the dams. Maternal and fetal GGTP activity in the EtOH rats was significantly higher than that of pair-fed controls, whereas the GGTP activity observed in the Siliphos(R)/EtOH rats was not elevated. Fetal mortality rates in the EtOH rats significantly exceeded those of all three other groups.  相似文献   

8.
Two new hepatoprotective stilbene glycosides from Acer mono leaves   总被引:1,自引:0,他引:1  
Two new stilbene glycosides, 5-O-methyl-(E)-resveratrol 3-O-beta-d-glucopyranoside (1) and 5-O-methyl-(E)-resveratrol 3-O-beta-D-apiofuranosyl-(1-->6)-beta-d-glucopyranoside (2), were isolated from the leaves of Acer mono, along with seven known compounds. Among these compounds, 1, 2, and quercetin (3) showed significant hepatoprotective activities against H(2)O(2)-induced toxicity in primary cultures of rat hepatocytes.  相似文献   

9.
Three new cycloartane glycosides have been isolated from Astragalus bicuspis. They were identified as 6alpha-hydroxy-3-O-beta-xylopyranosyloxy-24,25,26,27-tetranor-9,19-cyclolanosta-16,23-lactone (1), 6alpha-hydroxy-23-methoxy-16beta,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-beta-xyloside (2), and 23(R),24(S),25(R),26(S)-16beta/23,23/26,24/25-triepoxy-6alpha,26-dihydroxy-9,19-cyclolanosta-3-O-beta-xyloside (3), on the basis of their spectroscopic data. Two known cycloartane derivatives, 4 and 5, were also obtained from this plant. Compounds 2-5 were tested for leishmanicidal activity against Leishmania major promastigotes and for cytotoxicity against 3T3 cancer cells.  相似文献   

10.
Six new pregnane glycosides, four of them sulfated derivatives, were isolated from small branches of Periploca graeca. The compounds were identified as 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-en-20-ol-3beta-yl O-(2-O-acetyl-beta-D-digitalopyranosyl)-(1-->4)-beta-D-cymaropyranoside (1), 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-en-20-ol-3beta-yl O-beta-D-oleandropyranosyl-(1-->4)-beta-D-oleandropyranoside (2), 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-en-20-ol-3beta-yl O-beta-D-oleandropyranoside (3), 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-ene-3beta,20-diol (4), 20-O-[(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl-(1-->2)-beta-D-digitalopyranosyl)oxy]pregn-5-en-16beta-ol-3beta-yl O-beta-D-digitalopyranosyl-(1-->4)-beta-d-cymaropyranoside (5), and calogenin 3-O-beta-D-digitalopyranoside-20-O-beta-D-canaropyranoside (6). Three pregnane glycosides, previously reported from the genus Periploca, were also isolated. Structures were established on the basis of spectroscopic analyses, including 1D and 2D NMR experiments, HRESIMS, elemental analysis, and chemical degradation.  相似文献   

11.
Five non-sulfated triterpene glycosides, synallactosides A(1) (1), A(2) (2), B(1) (3), B(2) (4), and C (5), have been isolated from the sea cucumber Synallactes nozawai. Their structures have been deduced by extensive analysis of NMR and mass spectra. The glycosides 2-5 are new glycosides. Glycosides 2-4 have carbohydrate chains without precedent in the glycosides from sea cucumbers. This is the first time glycosides are found in members of the family Synallactidae.  相似文献   

12.
Bioassay-directed fractionation of an anti-inflammatory CHCl(3)-MeOH (9:1) extract of leaves of Vernonia colorata, using a carrageenan-induced rat paw model, led to the isolation of six new compounds (1-6).These were assigned as two new androst-8-en glycosides, 3-O-[beta-d-galactopyranosyl-(1-2)-[beta-d-glucopyranosyl-(1-->6)]-beta-d-glucopyranoside]-5alpha,14alpha-androst-8-ene (1) and 3-O-[beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside]-5alpha,14alpha-androst-8-ene (2), two new stigmastane-type glycosides, 3beta,21,24-trihydroxy-21,23;22,28;26,28-triepoxy-5alpha-stigmasta-8(9),14(15)-dien-3-O-beta-d-galactopyranosyl-(1-->2)-beta-d-glucopyranoside (3) and 3beta,21,24-trihydroxy-21,23;22,28;26,28-triepoxy-5alpha-stigmasta-8(9),14(15)-dien-3-O-beta-d-galactopyranosyl-(1-->2)-beta-d-(6-acetyl)glucopyranoside (4), and two new stigmastane-type steroids, 3beta,25,29-trihydroxy-5alpha-stigmasta-8(9),14(15),24Z(28)-triene (5) and 3beta,23,25-trihydroxy-24,28-epoxy-5alpha-stigmasta-8(9),14(15)-diene (6). The structures of 1-6 were elucidated by spectral and chemical studies. Compounds 1-6 were tested for the anti-inflammatory activity, but all were inactive or weakly inactive as anti-inflammatory agents.  相似文献   

13.
??OBJECTIVE To study the chemical constituents and their proliferation activity on rat osteoblasts of Semen Sojae Praeparatum. METHODS The compounds were isolated by chromatography on silica gel column,MCI and sephadex LH-20 column. Their structures were elucidated by spectral analysis. The proliferation test was performed by using rat osteoblasts with MTT assays in vitro. RESULTS Twelve compounds were obtained and identified as daidzin(1), daidzein(2),genistein(3), genistin(4), glycitein(5), glycitin(6),apigenin(7), ??-sitosterol(8), stigmasterol(9), campesterol(10), syringaldehyde(11), syringic acid(12), respectively. CONCLUSION Compounds 5-11 are isolated from Semen Sojae Praeparatum for the first time. The five isoflavones show proliferation activity on rat osteoblasts, and aglycones proved to show better activity than glycosides.
  相似文献   

14.
注射用水飞蓟宾脂质纳米乳中水飞蓟宾含量测定   总被引:2,自引:1,他引:2       下载免费PDF全文
 目的建立直接紫外分光光度法,测定最新研制的注射用水飞蓟宾脂质纳米乳中水飞蓟宾含量的方法。方法选用1 mol·L-1的NaOH碱溶液破乳,弃去以氯仿为萃取剂提取的纳米乳油相,水相层由纳米乳中释放出的水飞蓟宾以无水乙醇溶解,HCl中和,于288 nm处直接测定吸光度,计算水飞蓟宾的含量。结果水飞蓟宾在0.297 0~1.784 mg·mL-1浓度范围内呈线性,r=0.999 9;高、中、低3种浓度的萃取回收率和方法回收率分别为96.08%~98.95%和99.72%~100.5%,n=3;日内和日间RSD分别为0.37%和3.6%,n=5。结论建立的方法准确度高,重现性好,本实验为水飞蓟宾脂质纳米乳新剂型质量标准的制定提供了方法学依据。  相似文献   

15.
Four chalcone glycosides (1-4), including three new natural products, and three flavanones (5-7) were isolated from the methanol extract of stem bark of Maclura tinctoria. The new compounds have been characterized as 4'-O-beta-D-(2' '-p-coumaroyl)glucopyranosyl-4,2',3'-trihydroxychalcone (1), 4'-O-beta-D-(2' '-p-coumaroyl-6' '-acetyl)glucopyranosyl-4,2',3'-trihydroxychalcone (2), and 3'-(3-methyl-2-butenyl)-4'-O-beta-D-glucopyranosyl-4,2'-dihydroxychalcone (3); the known derivatives were elucidated as 4'-O-beta-D-(2' '-acetyl-6' '-cinnamoyl)glucopyranosyl-4,2',3'-trihydroxychalcone (4), eriodictyol 7-O-beta-D-glucopyranoside (5), naringenin (6), and naringenin 4'-O-beta-D-glucopyranoside (7). Their structures were determined by 1D and 2D NMR and ESIMS. The antioxidant activity of all the isolated compounds was determined by measuring free-radical-scavenging effects using two different assays, namely, the Trolox Equivalent Antioxidant Capacity (TEAC) assay and the coupled oxidation of beta-carotene and linoleic acid (autoxidation assay). The results showed that compound 3 was the most active in both antioxidant assays.  相似文献   

16.
Three new monosulfated triterpene glycosides, calcigerosides B (2), C(1) (3), and C(2) (4), along with the known cucumarioside G(2) (1), have been isolated from the sea cucumber Pentamera calcigera. Their structures have been deduced from extensive spectral analysis (NMR and MS) and chemical evidence. Compounds 2-4 present a novel pentasacharide chain never reported before in sea cucumber triterpene glycosides. The desulfated derivatives of calcigerosides B, C(1), and C(2) (5, 7, and 9, respectively) showed moderate cytotoxicity (IC(50) = 5 microg/mL) against a selection of four human and mouse tumor cell lines.  相似文献   

17.
Aldose reductase, the principal enzyme of the polyol pathway, has been shown to play an important role in the complications associated with diabetes. A methanol extract of the stamens of Nelumbo nucifera Gaertn. was shown to exert an inhibitory effect on rat lens aldose reductase (RLAR), and thus was fractionated using several organic solvents, including dichloromethane, ethyl acetate and n-butanol. The ethyl acetate-soluble fraction, which manifested potent RLAR-inhibitory properties, was then purified further via repeated measures of silica gel and Sephadex LH-20 column chromatography. Thirteen flavonoids: kaempferol (1) and seven of its glycosides (2-9), myricetin 3',5'-dimethylether 3-O-beta-d-glucopyranoside (10), quercetin 3-O-beta-d-glucopyranoside (11) and two isorhamnetin glycosides (12, 13) were isolated from N. nucifera, as well as four non-flavonoid compounds: adenine (14), myo-inositol (15), arbutin (16) and beta-sitosterol glucopyranoside (17). These compounds were all assessed with regard to their RLAR-inhibitory properties. Among the isolated flavonoids, those harboring 3-O-alpha-l-rhamnopyranosyl-(1-->6)-beta-d-glucopyranoside groups in their C rings, including kaempferol 3-O-alpha-l-rhamnopyranosyl-(1-->6)-beta-d-glucopyranoside (5) and isorhamnetin 3-O-alpha-l-rhamnopyranosyl-(1-->6)-beta-d-glucopyranoside (13), were determined to exhibit the highest degree of rat lens aldose reductase inhibitory activity in vitro, evidencing IC(50) values (concentration required for a 50% inhibition of enzyme activity) of 5.6 and 9.0 microm, respectively.  相似文献   

18.
目的:探讨清肝调脂饮对非酒精性脂肪性肝炎(NASH)大鼠脂质过氧化反应的干预机制.方法:Wistar大鼠70只,除10只作为正常对照组外,余60只建立以高脂饲料(基础饲料88%,猪油10%,胆固醇1.5%,胆盐o.5%)诱导的非酒精性脂肪性肝炎大鼠模型并随机分为5组,除模型组外,造模同时ig清肝调脂饮低、中、高剂量组(4.59,9.18,18.39 g·kg-1)和西利宾胺组(27 mg·kg-1,ig)分别按临床等效剂量的0.5,1,2和1倍剂量药物治疗.实验12周,大鼠全部处死.检测各组大鼠血清丙氨酸转氨酶(ALT),天冬氨酸转氨酶(AST),甘油三酯(TG)含量,肝组织匀浆肿瘤坏死因子(TNF-α),丙二醛(MDA)含量以及超氧化物歧化酶(SOD)活性;肝组织行CD14,细胞色素P450 2E1( CYP2E1)免疫组化染色,阳性结果作定量分析.结果:与空白对照组比较,模型组ALT(62.57±17.08)U·L-1,TNF-α( 902.00±22.66) pg·mg-1,CYP2E1阳性率(0.88±0.07),SOD(81.78±2.24) U·mg-1各指标均显示异常(P <0.05,P<0.01);与模型组比较,各用药组均能不同程度的改善以上各指标(P<0.05,P<0.01).在降低TG,TN F-α方面,清肝调脂饮高剂量组明显优于西药对照组(P<0.01);而对其他各指标的改善,清肝调脂饮各剂量组与西药对照组疗效无显著差异.结论:清肝调脂饮具有降低脂质过氧化反应、提高抗氧化能力的作用,从而减轻NASH肝细胞变性坏死程度.  相似文献   

19.
Glycosides from the bark of Adina polycephala   总被引:1,自引:0,他引:1  
Four new dimeric phenolic glycosides (1- 4), a new iridoid diglycoside (5), and 15 known glycosides have been isolated from an ethanolic extract of the bark of Adina polycephala. Their structures were determined by spectroscopic and chemical methods. Compounds 1, 3, and 5 showed in vitro inhibitory activity against the release of beta-glucuronidase in rat polymorphonuclear leukocytes induced by platelet-activating factor.  相似文献   

20.
Investigation of the inhibitory fraction of Leucas aspera on prostaglandin-induced contraction in guinea pig ileum provided four new diterpenes, leucasperones A (1) and B (2) and leucasperols A (3) and B (4), and three new isopimarane glycosides, leucasperosides A, B, and C (5-7), together with the known compounds asperphenamate, maslinic acid, (-)-isololiolide, and linifolioside. The structures of the compounds were determined by detailed spectroscopic analysis. The configurations of 1 and 2 and the acetylated derivatives of 3 and 4 were determined by differential NOE analysis and CD data. Leucasperone A (1), leucasperosides A (5) and B (6), and linifolioside showed inhibition of prostaglandin-induced contractions.  相似文献   

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