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1.
为探究飞机草地上部分化学成分及其抑菌作用.采用正相硅胶、Sephadex LH-20等色谱方法,从飞机草乙酸乙酯提取物中得到10个化合物,根据1H NMR、13C NMR、MS波谱数据,分别鉴定为:5,6,7,4'-四甲氧基黄烷酮(1)、圣草素-7,4'-二甲醚(2)、5,7-二羟基-6,4'-二甲氧基黄酮(3)、二氢...  相似文献   

2.
Six flavonoids, five of them novel, have been isolated from the whole stem of Popowia cauliflora and identified as: baicalein trimethyl ether, 5-hydroxy-6,7-dimethoxyflavone, 5,7,8-trimethoxyflavanone, 2′-hydroxy-3′,4′,6′-trimethoxychalcone, 2′,3′,4′,6′-tetramethoxychalcone and 2′,4-dihydroxy-3′,4′,6′-trimethoxychalcone, on the basis of spectral data and simple chemical modifications. The value of 13C NMR in assigning the positions of methoxy substituents is briefly discussed.  相似文献   

3.
Poincianella pyramidalis (Fabaceae) is an endemic tree that grows in semiarid regions of Brazil. Phytochemical investigations on the bark roots of this plant led to the isolation of four new biflavonoids named (+)-5-hydroxy-7,4′-dimethoxyflavone-3α-2′′′-hydroxy-4′′′,4′′-dimethoxydihydrochalcone (1), (+)-5,7-dihydroxy-4′-methoxyflavone-3α-2′′′-hydroxy-4′′′,4′′-dimethoxydihydrochalcone (2), (−)-7-hydroxy-4′-methoxyflavone-3α-2′′′,4′′′-dihydroxy-4′′-methoxydihydrochalcone (3), (−)-7,4′-dihydroxy-flavanone-3,8-5′′,6′′,4′′-trihydroxy-flavone (4), and the previously identified compound 4,2′,4′,4′′,2′′′,4′′′-hexahydroxy-3,5′′′-bichalcone (rhuschalcone VI, 5). Their structures were determined by HR-ESI-MS and extensive analyses of NMR spectroscopic data.  相似文献   

4.
Cinnamic acid, 4-hydroxy-cinnamic acid, ferulic acid, methyl ferulate, sinapic acid, methyl 3-(4-hydroxy-3-methoxyphenyl)propanoate, 4-(1-hydroxyethyl)-2-methoxyphenol, vanillyl alcohol, 4-(hydroxymethyl)-2-methoxyphenol, 4-hydroxy-3-methoxybenzoic acid, 4-vinylphenol, 4-methylbenzaldehyde, N-[2-(1H-indol-3-yl)ethyl]acetamide, pinoresinol, syringaresinol, lariciresinol, 5,5'-dimethoxy-lariciresinol, threo-guaiacylglycerol-3-beta-4-syringaresinol ether and two new sesquilignans, namely, threo-guaiacylglycerol-alpha-O-methyl-beta-O-4-syringaresinol ether and threo-syringylglycerol-alpha-O-methyl-beta-O-4-syringaresinol ether, were isolated and identified as components of Chenopodium album. Constitutions were established on the basis of spectroscopic data, including two-dimensional NMR analyses.  相似文献   

5.
Two structurally interesting new norlignans named 2-hydroxy-4-[4-hydroxyphenyl-(4-hydroxy-3-methoxybenzyl)]-3-(3,5-dihydroxyphenyl)tetrahydrofuran (1) (pouzolignan A), and 1,4-dihydroxy-3-[4-hydroxyphenyl-(4-hydroxy-3-methoxybenzyl)]-2-(3,5-dihydroxyphenyl)butane (2) (pouzolignan B), were isolated from the EtOAc fraction of the methanol extract of Pouzolzia occidentalis. Compound 3, the methyl ether of 1, most likely an artifact, was also isolated. The overall structures and relative stereochemistry were elucidated largely by analysis of 1D and 2D NMR spectral data.  相似文献   

6.
采用硅胶和凝胶柱色谱,以及制备性薄层色谱等多种分离手段,从盘龙参全草中分离得到了2个新的9,10-二氢菲类化合物,运用NMR和MS等波谱技术分别鉴定为4-羟基-2-甲氧基-8-呋喃[4′,5′:7,8]-9,10-二氢菲(1),4-羟基-2-甲氧基-8-{2',2'-二甲基吡喃[5',6':7,8]}-9,10-二氢菲(2).  相似文献   

7.
从青蕨的乙酸乙酯提取物中分离得到6个化合物,通过化学方法及波谱分析,分别将其结构鉴定为木香素Ⅲ(1),7-甲氧基鬼灯擎素(2),扶桑甾醇(3),5-(3′-甲基丁基)-8-甲氧基呋喃香豆素(4),2-(3′-羟基-3′-甲基)丁基-4-羟基-5-甲氧基苯酚-1-O-β-D匍吡喃糖苷(青蕨素Ⅰ)(5)和2-(3′-羟基-3′-甲基)丁基-4-羟基-3,6-二甲氧基苯酚-1-O-β-D-匍吡喃糖苷(青蕨素Ⅱ)(6)。化合物5和6为新化合物,化合物1,2,3和4为首次从该植物中分离得到。  相似文献   

8.
From the petroleum ether extract of the rhizomes of Tamus communis, the 7-hydroxy-2,3,4,8-tetramethoxyphenanthrene (1) was isolated, together with the known 2,3,4-trimethoxy-7,8-methylenedioxyphenanthrene (2), 3-hydroxy-2,4,-dimethoxy-7,8-methylenedioxyphenanthrene (3), 2-hydroxy-3,5,7-trimethoxyphenanthrene (4) and 2-hydroxy-3,5,7-trimethoxy-9,10-dihydrophenanthrene (5), through cytotoxic assay guidance. The structures were determined by means of HREIMS, (1)H NMR, JMOD and NOESY experiments. The cytotoxic effects of the isolated compounds were tested on cervix adenocarcinoma (HeLa) cells, with the MTT assay. The results demonstrated that, with the exception of 2, all these compounds displayed pronounced cytotoxic activity; especially 1 and 3 exhibited significant cell growth inhibitory effects, with IC(50)=8.52+/-0.70 and 3.64+/-0.12 microM, respectively.  相似文献   

9.
为研究柯拉斯那(Aquilaria crassna Pierre ex Lecomte)沉香的化学成分。实验采用多种柱色谱方法从该沉香中分离得到9个2-(2-苯乙基)色酮类化合物,通过现代波谱学技术分别鉴定为6-甲氧基-2-[2-(3′-羟基-4′-甲氧基苯基)乙基]色酮(1)、5-羟基-6-甲氧基-2-[2-(3′-羟基-4′-甲氧基苯基)乙基]色酮(2)、tetrahydrochromone F(3)、6-甲氧基-2-[2-(3′-甲氧基-4′-羟基苯基)乙基]色酮(4)、6-甲氧基-7-羟基-2-[2-(4′-甲氧基苯基)乙基]色酮(5)、6,7-二甲氧基-2-[2-(3′-羟基-4′-甲氧基苯基)乙基]色酮(6)、6,7-二甲氧基-2-[2-(4′-甲氧基苯基)乙基]色酮(7)、6-羟基-2-[2-(4′-羟基苯基)乙基]色酮(8)、5-羟基-2-[2-(2′-羟基苯基)乙基]色酮(9)。化合物2、3和5~9均为首次从柯拉斯那所得沉香中分离得到。采用MTT法对单体化合物的细胞毒活性进行测试,测试结果表明,化合物1,2和4具有微弱的细胞毒活性。  相似文献   

10.
The CHCl3-soluble fraction of the whole plant of Duranta repens showed anti-plasmodial activity against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum, with IC50 values of 8.5?±?0.9 and 10.2?±?1.5?μg/mL, respectively. From this fraction, two new flavonoid glycosides, 7-O-α-d-glucopyranosyl-3,4′-dihydroxy-3′-(4-hydroxy-3-methylbutyl)-5,6-dimethoxyflavone (1) and 7-O-α-d-glucopyranosyl(6′′′-p-hydroxcinnamoyl)-3,4′-dihydroxy-3′-(4-hydroxy-3-methylbutyl)-5,6-dimethoxyflavone (2), along with five known flavonoids, 3,7,4′-trihydroxy-3′-(4-hydroxy-3-methylbutyl)-5,6-dimethoxyflavone (3), 3,7-dihydroxy-3′-(4-hydroxy-3-methylbutyl)-5,6,4′-trimethoxyflavone (4), 5,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-3,6,4′-trimethoxyflavone (5), 3,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-buten-yl)-5,6,4′-trimethoxyflavone (6), and 7-O-α-d-glucopyranosyl-3,5-dihydroxy-3′-(4′′-acetoxy-3′′-methylbutyl)-6,4′-dimethoxyflavone (7), have been isolated as anti-plasmodial principles. Their structures were deduced by spectroscopic analysis including 1D and 2D NMR techniques. The compounds (1–7) showed potent anti-plasmodial activities against D6 and W2 strains of Plasmodium falciparum, with IC50 values in the range of 5.2–13.5?μM and 5.9–13.1?μM, respectively.  相似文献   

11.
为研究马尾伸筋草(Lycopodium fargesii Hert.)的化学成分及其抗骨质疏松活性,采用硅胶、MCI、RP-18、Sephadex LH-20柱色谱及半制备高效液相色谱对马尾伸筋草的乙醇提取物进行系统分离,从乙酸乙酯部位中得到18个化合物,综合利用NMR、HR-ESI-MS等技术,分析鉴定化合物的结构,分别鉴定为α-芒柄蜡素(1)、26-去甲-8-氧化-α-芒柄蜡素(2)、serrat-14-en-3β,21α,24-triol(3)、serrat-14-en-3β,21β,24-triol(4)、1,20-eicosanediol(5)、二十三烷(6)、glycerolmonolinoleate(7)、glyceryl linolentate(8)、3-(4′-formylphenoxy)-4-methoxybenzaldehyde(9)、芹菜素(10)、对羟基苯甲醛(11)、香草酸(12)、3-羟基-4-甲氧基苯甲酸(13)、2-羟基-1-(4-羟基-3-甲氧基-苯基)-丙基-1-酮(14)、3-甲氧基-4-羟基桂皮醛(15)、8-acetoxy-5-hydroxyumbelliprenin(16)、trans-4-hydroxy-2-nonenoic acid(17)和正十烷硫醇(18)。化合物1~18均为首次从马尾伸筋草中分离得到,其中化合物16对破骨细胞活性具有显著的抑制作用,其IC50为1.98μM。  相似文献   

12.
Nine analogues of methyl acarviosin (1), the core structure of acarbose and its homologues, the 6-hydroxy-(2), 6-azido-(3), 6-amino- (4), 6-acetamido-(5), 6-methoxy-(6), 6-hydroxy-2-O-methyl-(8), and 6-hydroxy-3-O-methyl derivatives (9), including the 5-methoxycarbonyl analogue (7) and 3,6-anhydro derivative (10) of 2, were synthesized by chemical modification of the sugar part of 2 derived by condensation of methyl 3,4-anhydro-alpha-D-galactopyranoside (17) and 4,7:5,6-di-O-isopropylidenevalienamine (26) or by direct coupling between 26 and the 6-substituted methyl 3,4-anhydro-alpha-D-galactopyranoside derivatives. Compounds 2 and 8 show notable inhibitory activity against yeast alpha-D-glucosidase almost comparable to that of 1. Introduction of a polar substituent at C-6 of 1 decreases the inhibitory activity. Interestingly, inversion of the conformation of the sugar part of 1 by introduction of the 3,6-anhydro bridge elicits almost no effect on the inhibitory activity.  相似文献   

13.
Alkaline degradation of Aurasperone A, C32H26O10, gave a binaphthyl (IIa), m.p. 255°C and acetone. (IIa) afforded a tetraacetate (IIb), C32H30O12 m.p. 219°C and a tetramethyl ether (IId), C28H30O8, m.p. 188°C. These facts along with the NMR spectra of aurasperone A and (IIb) confirm that aurasperone A is a dimeric 2-methyl-5-hydroxy-6,8-dimethoxy-4H-naphtho[2,3-b]pyran-4-one with asymmetric C-C linkage (7-10′ or 9-10′). The ether (IId) is not identical with 1,1′ ,3,3′ ?6,6′ ,8,8′-octamethoxy-4,4′-binaphthyl. Thus, it follows that (IId) is a 2,4′-binaphthyl and hence aurasperone A is 2,2′-dimethyl-5,5′- dihydroxy-6,6′,8,8′-tetrahydroxy-7,10′-bi[4H-naphtho[2,3-b]pyran-4-one] (I).  相似文献   

14.
对苏铁(Cycas revoluta)的化学成分进行研究,采用多种色谱技术(硅胶、氧化铝和Sephadex LH-20等)从苏铁茎的乙酸乙酯部位分离得到16个化合物,其结构由HR-ESI-MS、1H和13CNMR等波谱学方法鉴定为5,6-去氢柳杉酚(1)、cunningine A (2)、6-羟基-5,6-去氢柳杉酚(3)、6α-羟基-7-氧代弥罗松酚(4)、ligballinol (5)、xanthoxyol (6)、callislignan A (7)、(2R,3R)-bis[(4-hydroxy-3-methoxyphenyl) methyl]-1,4-diacetate (8)、开环异落叶松脂醇(9)、二氢山柰酚(10)、4'-甲基木犀草素(11)、5-methoxypinosylvin (12)、N-benzoylphenyl alaninol(13)、(E,4R)-4-hydroxy-4,5,5-trimethyl-3-(3-oxobut-1-enyl) cyclohex-2-enone (14)、3-hydroxy-5α,6α-epoxy-β-io-none (15)和acuminantin (16)。以上化合物均为首次从苏铁属植物中分离得到,其中化合物13和16为首次以天然产物报道。本研究还首次发现了苏铁属植物中含有松香烷型二萜类(1~4)和芪类(12)化合物。化合物11具有中等的体外α-葡萄糖苷酶抑制活性。  相似文献   

15.
A new optically active flavan aglucone, 7-hydroxy-3′,4′-methylenedioxyflavan, and its 7-glucoside have been isolated from the bulbs of Zephyranthes flava, collected at flowering. Additionally, two known flavans, 7,4′-dihydroxy-3′-methoxyflavan and 7-methoxy-2′-hydroxy-4′,5′-methylenedioxyflavan, have been isolated for the first time from this species. The structures of these flavans have been established by comprehensive analyses (UV, IR, 1H NMR, 13C NMR, mass spectrometry, [α]D) of the compounds and their acetates, and also by chemical correlation.  相似文献   

16.
Rapid absorption and degradation of chlomethoxynil were observed in seedlings of rice and barnyard millet. The amounts of absorption by rice and barnyard millet, at the 2-leaf and 4-leaf stages of plants, were determined in water and soil cultures.

The major metabolic products of chlomethoxynil were 2,4-dichlorophenyl 3′-hydroxy-4′-nitrophenyl ether, 2,4-dichlorophenyl 3′-methoxy-4′-aminophenyl ether and their conjugates, and 2,4-dichlorophenyl 3′-methoxy-4′-acetylaminophenyl ether. Several minor unknown substances were also detected. A major metabolic pathway of chlomethoxynil in plants was postulated.  相似文献   

17.
Three new phenolic acid derivatives, 1-methyl glyceric acid-2-vanillic acid ether (1), methyl 2-hydroxy-6-(3-methoxy-3-oxoprop-1-en-2-yloxy) benzoate (2), methyl 2-hydroxy-6-(1-Carboxyvinyloxy) benzoate (3) and five known compounds namely 4-hydroxymellein (4), mellein methyl ether (5), 2-methyl-5,7-dihydroxychromone (6), latifolicinin C (7) and oresbiusin A (8) were isolated from Oenothera biennis L. The structures of these secondary metabolites were elucidated using different spectroscopic techniques, including 1H, 13C NMR, HR-ESI-MS, ECD and comparison with published data.  相似文献   

18.
The trunk wood of Iryanthera elliptica Ducke (Myristicaceae) contains, besides 2-(ω-piperonyltridecyl) -4-methylidenetetronic acid (iryelliptin), three biogenetically related compounds: (±)-7,4′-dihydroxy-3′-methoxyflavan, 1-(4′-hydroxy-2′-methoxyphenyl)- 3-(4″-hydroxy-3″-methoxyphenyl)-propane and spiro-[3-methoxy-2,5-cyclohexadien-1.1′-6′,7′- dihydroxy-5′-methoxy-1′,2′,3′,4′-tetrahydronaphthalen]-4-one-(spiroelliptin). Spiroelliptin rearranges upon methylation to 2,2′-trimethylene-3,4,5,4′,5′-penta-methoxybiphenyl.  相似文献   

19.
(2R,3R)-2 3-Dihydro-2-(4′-hydroxy-3′-methoxyphenyl)-3-(hydroxymethyl)-7-methoxy-5-benzofuranpropanol 4′-O-β-d-glucopyranoside [dihydrodehydrodiconiferyl alcohol glucoside], (2R,3R)-2 3-dihydro-7-hydroxy-2-(4′-hydroxy-3′-methoxyphenyl)-3-(hydroxymethyl)-5-benzofuranpropanol 4′-O-β-d-glucopyranoside and 4′-O-α-l-rhamnopyranoside, 1-(4′-hydroxy-3′-methoxyphenyl)-2- [2″-hydroxy-4″-(3-hydroxypropyl)phenoxy]-1, 3-propanediol 1-O-β-d-glucopyranoside and 4′-O-β-d-xylopyranoside, 2,3-bis[(4′-hydroxy-3′-methoxyphenyl)-methyl]-1,4-butanediol 1-O-β-d-glucopyranoside [(?)-seco-isolariciresinol glucoside] and (1R,2S,3S)-1,2,3,4-tetrahydro-7-hydroxy-1-(4′-hydroxy-3′-methoxyphenyl)-6-methoxy-2 3-naphthalenedimethanol α2-O-β-d-xylopyranoside [(?)-isolariciresinol xyloside] have been isolated from needles of Picea abies and identified.  相似文献   

20.
白叶香茶菜中的紫罗兰酮衍生物   总被引:2,自引:0,他引:2  
从白叶香茶菜Isodon leucophyllus(Dunn)Kudo地上部分的丙酮提取物中,分离得到1个新的紫罗兰酮类化合物和6个黄酮类化合物,经IR,UV,MS,NMR波谱数据分析,其结构分别确定为:13—羧基布卢姆醇C(1),5,7,3′,4′—四甲氧基黄酮(2),线蓟素(3),5—羟基—6,7,3′,4′—四甲氧基黄酮(4),3′—羟基—5,7,8,4′—四甲氧基黄酮(5),异甜橙素(6)和异槲皮素(7)。其中,化合物2—7均为首次从该植物中得到。  相似文献   

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