Flavonoids and phenolic acids from the aerial parts of Alyssum alyssoides L. (Brassicaceae)

Two phenolic acids (1 and 2) and seven flavonoids (3–9) were isolated from the aerial parts of Alyssum alyssoides (Brassicaceae). All these compounds (1–9) were isolated from this particular species for the first time. Their structures were identified, on the basis of MS and NMR spectra as: p-hydroxy-benzoic acid (1), 3-methoxy-4-hydroxybenzoic acid (vanillic acid) (2), kaempferol 3-O-β-D-glucopyranoside (astragalin) (3), kaempferol 3-O-(6″-α-L-rhamnopyranosyl)-β-D-glucopyranoside (nicotiflorin) (4), quercetin 3-O-β-D-glucopyranoside (isoquercetin) (5), quercetin 3-O-β-D-galactopyranoside (hyperoside) (6), isorhamnetin 3-O-β-D-glucopyranoside (7), isorhamnetin 3-O-β-D-galactopyranoside (8) and isorhamnetin 3-O-(6″-α-L-rhamnopyranosyl)-β-D-glucopyranoside (narcissin) (9). The chemotaxonomic significance of these compounds was summarized.     

青蕨植物化学成分的研究

从青蕨根部的乙酸乙酯提取物中分离得到4个化合物。通过化学及波谱分析鉴定其结构为：saucerneol D(1),dehydrogoniothalamin(2),1-acetoxyl-2-piperonyl-6-[6-methoxyl-piperonyl]3,7-dioxabicyclo-[3,3,0]-octane(3) and 5,5′-dihydroxy-3-methoxy-6,8,3″,3″-tetramethylpyran-(3′,4′)flavone-7-O-[β—D—apiofuranosyl-(1→6)]-β-D-glucopyranoside(4)。其中化合物(4)为新化合物,化合物(1)为首次从该属植物中分离得到。     

Acetylated allose-containing flavonoid glucosides from Stachys anisochila

In continuation of our chemosystematic study of Stachys (Labiatae) we have isolated the previously reported isoscutellarein 7-O-[6″'-O-acetyl-β-D-allopyranosyl-(1 → 2)-β-D-glucopyranoside] (1) and 3′-hydroxy-4′-O-methylisoscutellarein 7-O-[6″'-O-acetyl-β-D-allopyranosyl-(1 → 2)-β-D-glucopyranoside] (4) and four new allose-containing flavonoid glycosides from S. anisochila. The new glycosides are hypolaetin 7-O-[6″'-O-acetyl-β-D-allopyranosyl-(1 → 2)-β-D-glucopyranside] (6) as well as the three corresponding diacetyl analogues of 1, 4 and 6, isoscutellarein 7-O-[6″'-O-acetyl-β-D-allopyranosyl-(1 → 2)-6″-O-acetyl-β-D-glucopyranoside], 3′-hydroxy-4′-O-methylisoscutellarein 7-O-[6″'-O-acetyl-β-D-allopyranosyl-(1 → 2)-6″-O-acetyl-β-D-glucopyranoside] and hypolaetin 7-O-[6″'-O-acetyl-β-D-allopyranosyl-(1 → 2)-6″-O-acetyl-β-D-glucopyranoside]. Extensive two-dimensional NMR studies (proton-carbon correlations, COSY experiments) allowed assignment of all ¹H NMR sugar signals and a correction of the ¹³C NMR signal assignments for C-2 and C-3 of the allose.     

5-Methyl ether flavone glucosides from the leaves of Bruguiera gymnorrhiza

Two new 5-methyl ether flavone glucosides (7,4′,5′-trihydroxy-5,3′-dimethoxyflavone 7-O-β-D-glucopyranoside and 7,4′-dihydroxy-5-methoxyflavone 7-O-β-D-glucopyranoside) were isolated from the leaves of Thai mangrove Bruguiera gymnorrhiza together with 7,3′,4′,5′-tetrahydroxy-5-methoxyflavone, 7,4′,5′-trihydroxy-5,3′-dimethoxyflavone, luteolin 5-methyl ether 7-O-β-D-glucopyranoside, 7,4′-dihydroxy-5,3′-dimethoxyflavone 7-O-β-D-glucopyranoside, quercetin 3-O-β-D-glucopyranoside, rutin, kaempferol 3-O-rutinoside, myricetin 3-O-rutinoside and an aryl-tetralin lignan rhamnoside. The structure of a lignan rhamnoside was found to be related to racemiside, an isolated compound from Cotoneaster racemiflora, and also discussed. Structure determinations were based on analyses of physical and spectroscopic data including 1D- and 2D-NMR.     

Flavonol glycosides acylated with 3-hydroxy-3-methylglutaric acid as systematic characters in Rosa

LC–UV–MS/MS analysis of leaf extracts from 146 accessions of 71 species of Rosa revealed that some taxa accumulated flavonol O-glycosides acylated with 3-hydroxy-3-methylglutaric acid, which are relatively uncommon in plants. The structures of two previously unrecorded examples isolated from Rosa spinosissima L. (syn. Rosa pimpinellifolia L.) were elucidated using spectroscopic and chemical methods as the 3-O-α-l-rhamnopyranosyl-(1 → 2)-[6-O-(3-hydroxy-3-methylglutaryl)-β-d-galactopyranosides] of kaempferol (3,5,7,4′-tetrahydroxyflavone) and quercetin (3,5,7,3′,4′-pentahydroxyflavone). The corresponding 3-O-[6-O-(3-hydroxy-3-methylglutaryl)-β-d-galactopyranoside] of quercetin was also present in R. spinosissima, but at lower levels, together with 17 other flavonol O-glycosides for which structures were assigned using LC–UV–MS/MS. The distribution of flavonol 3-hydroxy-3-methylglutarylgalactosides in Rosa was limited to some species of subgenus Rosa section Pimpinellifoliae and Rosa roxburghii Sw. of the monotypic subgenus Platyrhodon, indicating that this character could be of value in phylogenetic analyses of the genus.     

Flavonol glycosides in leaves of Spinacia oleracea

Besides spinatoside (3,6-dimethoxy-5,7,3′,4′-tetrahydroxyflavone 4′-O-β-D-glucopyranuronide), three new flavonol glycosides have now been isolated from the polar fractions of the methanolic extract of Spinacia oleracea. They have been identified as patuletin 3-O-β-D-glucopyranosyl-(1 → 6)-[β-D-apiofuranosyl-(1 → 2)]-β-D-glucopyranoside, patuletin 3-O-β-gentiobioside and spinacetin 3-O-β-gentiobioside, respectively.     

瓦山锥化学成分研究(Ⅰ)

瓦山锥植物富含植物多酚类成分且资源丰富,目前尚无该植物化学成分及生物活性方面的报道。为了明确瓦山锥的物质基础,为该植物资源的合理开发与可持续利用提供科学依据,该研究采用Sephadex LH-20、Diaion HP20SS、Toyopearl HW-40F等多种柱层析方法对瓦山锥树叶乙醇提取物进行分离纯化,从中得到11个单体化合物,它们的结构经波谱数据分析及文献对照鉴定为没食子酸(1)、咖啡酸(2)、1-(3’,4’-二羟基肉桂酰)-环戊-2,3-二酚(3)、绿原酸(4)、绿原酸甲酯(5)、kaempferol 3-O-β-D-glucuronopyranoside(6)、kaempferol 3-O-{β-D-xylopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside}(7)、quercetin 3-O-β-D-glucuronopyranoside(8)、quercetin 3-O-β-glucuronide-6″-methyl ester(9)、芦丁(10)、quercetin5-O-[α-L-rham...     

Acylated flavonol glycosides from Delphinium staphisagria

An ethanolic extract of the aerial parts of Delphinium staphisagria L. from Tenerife yielded four new flavonol glycosides 2″-acetylastragalin, 2″-acetylpaeonoside, quercetin 3-O-(2-acetyl-β-glucopyranoside)-7-O-β-glucopyranoside and 2″-acetylpetiolaroside in addition to astragalin, isoquercitrin, paeonoside, kaempferol 3-O-β-glucopyranoside-7-O-α-rhamnopyranoside, petiolaroside and rutin.     

Further studies of flavonols of Clibadium (compositae)

The flavonoids of an additional eight species of Clibadium have been determined. The compounds are derivatives of kaempferol, quercetin and quercetagetin. O-Methylated quercetagetin derivatives were found in several taxa with the possibility that 6-methoxykaempferol may also exist in one collection. Kaempferol and quercetin exist as 3-O-glucosides, galactosides, rhamnosides, rutinosides and diglucosides although not all glycosides occur in each taxon. Quercetagetin derivatives occur as 7-O-glucosides. Observations on these newly investigated species confirm previous work in the genus that three types of flavonoid profiles exist: (1) kaempferol and quercetin 3-glycosides; (2) kaempferol and quercetin 3-glycosides plus quercetagetin 7-glucoside; and (3) kaempferol and quercetin 3-glycosides plus quercetagetin 7-glucoside and O-methylated derivatives of quercetagetin.     

Secondary metabolites of Rubus caesius (Rosaceae)

The European dewberry (Rubus caesius) is a perennial shrub that is widely distributed in Europe but can also be found in North America. In folk medicine, the European dewberry is used to treat hyperglycaemia, diarrhoea and inflammation. LC-MS analysis of the European dewberry confirmed the presence of 35 compounds, mostly flavonoids, phenolic acids and derivatives of ellagic acid. Phytochemical analysis of R. caesius leaves led to the isolation of nine phenolics, namely: quercetin 3-O-β-D-rutinoside (1), kaempferol 3-O-β-D-glucuronide (2), quercetin 3-O-β-D-glucuronide (3), methyl brevifolincarboxylate (4), kaempferol 3-O-β-D-(6″-O-(E)-p-coumaroyl)-glucoside (5), kaempferol (6), quercetin (7), pedunculagin (8), and ellagic acid (9). Compounds 1–8 were isolated from this species for the first time. The chemophenetic significance was discussed.     

Characterization and quantification of flavonoid glycosides in the Prunus genus by UPLC-DAD-QTOF/MS

Widely distributed in plants, flavonoids reduce the incidence of cancer and cardiovascular disease. In this study, flavonoid content and composition in members of the Prunus genus were evaluated using liquid chromatography with diode array and electrospray ionization mass spectrometric detection (UPLC-DAD-ESI/QTOF-MS). Flavonoids in plants of the Prunus genus include the basic structures of kaempferol, quercetin, and catechin, and exist as mono-, di-, or tri-glycoside compounds mono-acylated with acetic acid. A total of 23 individual flavonoids were isolated and confirmed, three of which appear to be newly identified compounds: quercetin 3-O-(2″-O-acetyl)neohesperidoside, quercetin 3-O-(4″-O-acetyl)rutinoside, and kaempferol 3-O-(4″-O-acetyl)rutinoside. Japanese apricot and Chinese plum contained the highest amounts of flavonoids in the Prunus genus. During the ripening stage of Japanese apricot, the total flavonol content was reduced, while the catechin content was increased.     

Phenolic derivatives from Ruprechtia polystachya and their inhibitory activities on the glucose-6-phosphatase system

Two new compounds, 5-methyl-2-(2-methylbutanoyl)phloroglucinol 1-O-(6-O-β-D-apiofuranosyl)-β-D-glucopyranoside (1) and trans-2,3-dihydrokaempferol 3-O-(4-O-sulfo)-α-L-arabinopyranoside (2), together with 14 known flavonoids, trans-dihydrokaempferol 3-O-α-L-arabinopyranoside (3), trans-taxifolin 3-O-α-L-arabinofuranoside (4), quercetin 3-O-α-L-rhamnopyranoside (5), quercetin 3'-O-α-L-arabinofuranoside (6), catechin 3-O-α-L-rhamnopyranoside (7), trans-taxifolin 3-O-α-L-arabinopyranoside (8), cis-dihydrokaempferol 3-O-α-L-arabinopyranoside (9), catechin (10), myricetin 3-O-α-L-rhamnopyranoside (11), quercetin 3-O-α-L-arabinopyranoside (12), quercetin 3-O-α-L-arabinofuranoside (13), quercetin 3-O-(3″-galloyl)-α-L-rhamnopyranoside (14), quercetin 3-O-(2″-galloyl)-α-L-rhamnopyranoside (15), and epicatechin 3-O-gallate (16), were isolated from the leaves of Ruprechtia polystachya Griseb. (Polygonaceae). Their structures were established on the basis of extensive 1D- and 2D-NMR experiments as well as MS analyses. All compounds, except 1, showed inhibition of the enzyme glucose-6-phosphatase in intact microsomes.     

Anthocyanins and flavonols from the blue flowers of six Meconopsis species in Bhutan

Blue flowers of six Bhutani Meconopsis species, M. bhutanica, M. bella, M. horridula, M. simplicifolia, M. primulina and M. polygonoides, were surveyed for anthocyanins and other flavonoids. Four anthocyanins were isolated and identified as cyanidin 3-O-sambubioside-7-O-glucoside (1), cyanidin 3-O-[xylosyl-(1 → 2)-(6″-malonylglucoside)]-7-O-glucoside (2), cyanidin 3-O-sambubioside (4) and cyanidin 3-O-[xylosyl-(1 → 2)-(6″-malonylglucoside)] (5). On the other hand, 12 flavonols were isolated from their Meconopsis species with various combination and characterized as kaempferol 3-O-glycosides (8–12), kaempferol 3,7-O-glycosides (13–16), quercetin 3-O-glycosides (17 and 18) and isorhamnetin 3-O-glycoside (19). Of six Meconopsis species which were surveyed in this experiment, anthocyanin and flavonol composition of five species except for M. horridula was clarified for the first time. Their Meconopsis species showed the different flavonoid profiles, respectively, and flavonoid diversity within the glycosylation level of Meconopsis flowers were indicated.     

Armenin and isoarmenin--two prenylated coumarins from the aerial parts of Artemisia armeniaca

The reversed-phase (RP) preparative HPLC analyses of the MeOH extract of the aerial parts of Artemisia armeniaca yielded four prenylated coumarins, 7-hydroxy-8-(4-hydroxy-3-methylbutoxy)coumarin (named armenin), 8-hydroxy-7-(4-hydroxy-3-methylbutoxy)coumarin (named isoarmenin), lacarol, and deoxylacarol, together with five other compounds, including three flavonoid glycosides, quercetin 3-O-β-D-glucopyranoside, rutin, and kaempferol 3-O-β-D-glucopyranoside, and chlorogenic acid, and tryptophan. (10E,12Z)-9-Hydroxyoctadeca-10,12-dienoic acid (β-dimorphecolic acid) was isolated from the CH(2)Cl(2) extract. Armenin and isoarmenin were new coumarins. Structures of all compounds were determined by spectroscopic means, including UV, MS, 1D- and 2D-NMR. The in vitro free-radical-scavenging property of the extracts and isolated compounds was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay.     

Flavonoid glycosides from needles of Pinus massoniana

Seven flavonoids have been isolated from Pinus massoniana needles and identified as taxifolin and its 3′-O-β-D-glucopyranoside, (+)-catechin, naringenin-7-O-β-D-glucopyranoside and three new flavonoid glycosides, 6-C-methylaromadendrin 7-O-β-D-glucopyranoside, taxifolin 3′-O-β-D-(6″-O-phenylacetyl)-glucopyranoside and eriodictyol 3′-O-β-D-glucopyranoside.     

Angkorensides A and B – Two anti-inflammatory acyl glycosides from Gardenia angkorensis

Two new acyl glycosides, angkorensides A and B (1 and 2) together with twelve known compounds including hedyotol C 7″-O-β-D-glucopyranoside (3), proanthocyanidin A-1 (4), (-)-epicatechin (5), (+)-lyoniresinol 3α-O-β-D-glucopyranoside (6), kaempferol-3-O-β-D-galactopyranoside (7), cuneataside E (8), 4-hydroxyacetophenone 4-O-(6′-O-β-D-apiofuranosyl)-β-D-glucopyranoside (9), cinnamtannin B-1 (10), aesculitannin B (11), quercetin 3-O-rham-(1−6)-β-D-galactopyranoside (12), quercetin 3-O-β-D-galactopyranoside (13), and proanthocyanidin A-2 (14) have been unprecedentedly isolated from Gardenia angkorensis Pit. Angkorensides A and B (1 and 2) showed moderate anti-inflammatory inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophages and the known compounds (4, 10-14) exhibited strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity.     

金花茶花化学成分的研究

采用反复硅胶柱色谱法、Sephadex LH-20柱色谱法、ODS柱色谱法、反复重结晶等方法对金花茶花的化学成分进行分离纯化,并通过理化常数测定和波谱分析等方法进行结构鉴定.从金花茶花的乙醇提取物中分离得到13个化合物,分别鉴定为:槲皮素(1)、槲皮素-7-O-β-D-葡萄糖苷(2)、槲皮素-3-O-β-D-葡萄糖苷(...     

Arbutin derivatives from the buds of Vaccinium dunalianum and their MS/MS spectrometric fragmentations

Four arbutin derivatives were isolated from the buds of Vaccinium dunalianum in which 4-hydroxyphenyl-6′-(3''-O-β-D-glucopyranosyl-4''-hydroxycinnamoyl)-O-β-D-glucopyranoside (1) was a new compound. The structure of the new compound was determined on the basis of NMR and HR-ESI-MS data. All the arbutin derivatives were subjected to the MS/MS analyses from which the MS/MS spectrometric fragmentations were summarized.     

Flavonoids of the flowers of tamarix nilotica

The ethyl ester of kaempferol 3-O-β-D-glucuronide, the methyl and ethyl esters of quercetin 3-O-β-D-glucuronide have been isolated from an aqueous acetone extract of the flowers of Tamarix nilotica. In addition kaempferol 3-O-sulphate-7,4′-dimethyl ether and the free aglycones were isolated. The structures were established by routine methods, by FAB-MS and by ¹³C NMR spectral measurements.     

桂火绳中化学成分的研究

从梧桐科火绳属桂火绳中提取分离到22个化合物,经结构鉴定为:羽扇豆醇(1),白桦脂酸(2),齐墩果酸(3),丁香脂素(4),(+)-异落叶松树脂醇(5),东莨菪内酯(6),对羟基肉桂酸(7),二十七碳酸单甘油酯(8),2-十八烯酸单甘油酯(9),sitoindosideⅡ(10),儿茶素(11),表儿茶素(12),表儿茶素3-O-β-D-吡喃木糖甙(13),山奈酚3-O-β-D-吡喃葡萄糖甙(14),5,7,4'-三羟基异黄酮(15),4'-O-methylgallocatechin(16),反式-二氢槲皮素-3-O-α-阿拉伯糖甙(17),顺式-二氢槲皮素-3-O-α-阿拉伯糖甙(18),反式-二氢槲皮素-3-O-β-吡喃葡萄糖甙(19),3,5,7,3',5'-五羟基-4'-甲氧基异黄酮(20),山奈酚-3-O-β-D-吡喃葡萄糖(6→1)-α-L-吡喃鼠李糖甙(21),以及槲皮素3-O-β-D-吡喃葡萄糖(6→1)-β-D-吡喃葡萄糖甙(22),这些化学成分首次从该属植物中分离出来。