Iridoid and phenylethanoid glucosides from Veronica lavaudiana

From an extract of Veronica (sect. Hebe) lavaudiana we have identified mannitol and isolated 11 iridoid glucosides, the carbohydrate ester hebitol II, and four phenylethanoid glycoside esters. Five of the iridoid glycosides are new; of these, lavaudiosides A, B, and C (2a, 3a, and 4) are 1-mannityl esters of 8-epiloganic acid, while 7e and 7f are 6'-O-caffeoyl derivatives of catalpol. The new phenylethanoid glycoside esters, heliosides A, B, and C (8b-d), are 6'-xylosyl derivatives of aragoside. The structures of the new compounds were elucidated mainly by spectroscopic analysis, but also by chemical degradation. We also demonstrated that the structures of the known glycosides globularitol and hebitols I and II should be revised. These compounds are derivatives of mannitol and not glucitol as previously believed.     

Verbaspinoside, a new iridoid glycoside from Verbascum spinosum

A new iridoid glycoside, verbaspinoside (1), was isolated from the aerial parts of Verbascum spinosum. Its structure was elucidated on the basis of chemical and spectral data as 6-O-[(2' '-O-trans-cinnamoyl)-alpha-L-rhamnopyranosyl]-catalpol. Additionally, three known iridoids (aucubin, catalpol, and ajugol) and three phenylpropanoid glycosides [acteoside, angoroside A (2), and angoroside C (3)] were isolated and identified.     

An iridoid glucoside from Euphrasia pectinata

A new iridoid glucoside, 5beta,6beta-dihydroxyboschnaloside (1), was isolated from the aerial parts of Euphrasia pectinata. Five known iridoid glucosides, 6beta-hydroxyboschnaloside (2), aucubin, euphroside, plantarenaloside, and geniposidic acid, and two known phenylethanoid glycosides, verbascoside (= acteoside) and leucosceptoside A, were also obtained and characterized. The structure of compound 1 was established by spectroscopic evidence.     

Steroidal glycosides from the aerial parts of Polianthes tuberosa

A chemical investigation of the aerial parts of Polianthes tuberosa resulted in the isolation of a new bisdesmosidic cholestane glycoside (1) and three new spirostanol saponins (2-4), along with a known cholestane glycoside. The structures of new glycosides were determined by spectroscopic analysis, including 2D NMR spectroscopic data, and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activity on HL-60 human promyelocytic leukemia cells.     

Effects of phenylpropanoid and iridoid glycosides on free radical-induced impairment of endothelium-dependent relaxation in rat aortic rings.

The protective effect of phenylpropanoid glycosides, forsythoside B and alyssonoside, and the iridoid glycoside lamiide, isolated from the aerial parts of Phlomis pungens var. pungens, against free radical-induced impairment of endothelium-dependent relaxation in isolated rat aorta was investigated. Aortic rings were exposed to free radicals by the electrolysis of the physiological bathing solution. Free radical-induced inhibition of the endothelium-dependent relaxation in response to acetylcholine was countered by incubation of the aortic rings before electrolysis with the aqueous extract (200 microg/ml), phenylpropanoid fraction (100 microg/ml) and iridoid fraction (150 microg/ml) of P. pungens var. pungens. Major components of the phenylpropanoid fraction forsythoside B and alyssonoside also prevented the inhibition of the acetylcholine response, at 10(-4) M concentration. However, the major component of iridoid fraction lamiide was found ineffective at the same concentration. The protective activity of phenylpropanoid glycosides against the free radical-induced impairment of endothelium-dependent relaxation may be related to their free radical scavenging property.     

Holothurins B(2), B(3), and B(4), new triterpene glycosides from mediterranean sea cucumbers of the genus holothuria

Triterpene glycosides of three species of the Mediterranean sea cucumbers Holothuria polii, Holothuria tubulosa, and Holothuria sp. were studied. Three new monosulfated biosides, holothurins B(2) (1), B(3) (2), and B(4) (3), along with the previously known holothurins A (4) and B (5) were isolated from the sea cucumber H. polii. Triterpene glycosides belonging to holothurin A and B groups were found in H. tubulosa, while only one individual glycoside, holothurin A (4), was isolated from Holothuria sp. Structures of new substances were elucidated on the basis of spectral data (2D NMR and MS). The significance of holothurins as chemotaxonomic markers of the animals belonging to the genus Holothuria and taxonomic status of some representatives of the holothurians studied are discussed.     

Triterpene glycosides from Antarctic sea cucumbers. 1. Structure of liouvillosides A1, A2, A3, B1, and B2 from the sea cucumber Staurocucumis liouvillei: new procedure for separation of highly polar glycoside fractions and taxonomic revision

Five new triterpene glycosides, liouvillosides A1 (1), A2 (2), A3 (3), B1 (4), and B2 (5), have been isolated from the Antarctic sea cucumber Staurocucumis liouviellei along with the known liouvilloside A(6), isolated earlier from the same species, and hemoiedemosides A (7) and B (8), isolated earlier from the Patagonian sea cucumber Hemioedema spectabilis. The isolation was carried out using a new chromatographic procedure including application of ion-pair reversed-phase chromatography followed by chiral chromatography on a cyclodextrin ChiraDex column. The structures of the new glycosides were elucidated using extensive NMR spectroscopy (1H and 13C NMR spectrometry, DEPT, 1H-(1)H COSY, HMBC, HMQC, and NOESY), ESI-FTMS, and CID MS/MS, and chemical transformations. Glycosides 1-3 are disulfated tetraosides and glycosides 4 and 5 are trisulfated tetraosides. Glycosides 2 and 3 contain 3-O-methylquinovose, found for the first time as a natural monosaccharide in sea cucumber glycosides. On the basis of analyses of glycoside structures a taxonomic revision is proposed.     

Acylated iridoid and phenylethanoid glycosides from the aerial parts of Scrophularia nodosa.

From the aerial parts of Scrophularia nodosa L. (Scrophulariaceae), eighteen acylated iridoid glycosides and nine phenylethanoid glycosides were isolated. The structures of eight new iridoid and two new phenylethanoid glycosides were elucidated on the basis of chemical and spectroscopic evidences.     

Sucrose esters and xanthone C-glycosides from the roots of Polygala sibirica.

Six new sucrose esters, sibiricoses A(1)-A(6) (1-6), two new xanthone C-glycosides, sibiricaxanthones A (7) and B (8), and a new acetophenone glycoside, sibiricaphenone (9), were isolated from the roots of Polygala sibirica together with six known glycosides. The structures of new compounds were elucidated on the basis of chemical and spectroscopic evidence. The structure of the known xanthone glycoside, polygalaxanthone III (10), was revised.     

Characterization of lipophilic pentasaccharides from beach morning glory (Ipomoea pes-caprae)

The hexane-soluble extract from the aerial parts of the herbal drug Ipomoea pes-caprae (beach morning-glory), through preparative-scale recycling HPLC, yielded six lipophilic glycosides, namely, five new pentasaccharides of jalapinolic acid, pescaproside A (1) and pescapreins I-IV (2-5), as well as the known stoloniferin III (6). Saponification of the crude resin glycoside mixture yielded simonic acid B (7) as the glycosidic acid component, whereas the esterifying residues of the natural oligosaccharides comprised five fatty acids: 2-methylpropanoic, (2S)-methylbutyric, n-hexanoic, n-decanoic, and n-dodecanoic acids. Pescaproside A (1), an acylated glycosidic acid methyl ester, is related structurally to the product obtained from the macrolactone hydrolysis of pescapreins I-IV (2-5). All the isolated compounds (1-6), characterized through high-field NMR spectroscopy, were found to be weakly cytotoxic to a small panel of cancer cell lines.     

Flavonoid, iridoid, and lignan glycosides from Putoria calabrica

From the aerial parts of Putoria calabrica, two new flavonol triglycosides were isolated and their structures were elucidated as quercetin-3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside]-7-O-beta-D-glucopyranoside (1, calabricoside A) and quercetin-3-O-[4' "-O-caffeoyl-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside]-7-O-beta-D-glucopyranoside (2, calabricoside B). Additionally, seven iridoid and three lignan glycosides were isolated and characterized. Radical scavenging activities of all compounds were determined by quantifying their effects on luminol-enhanced chemiluminescence in formyl-methionyl-leucyl-phenylalanine (FMLP) stimulated human polymorphonuclear neutrophils (PMNs). Calabricoside A and B showed strong radical scavenging activity with IC(50) values of 0.25 and 0.3 microM, respectively.     

Four new neuroprotective iridoid glycosides from Scrophularia buergeriana roots

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.     

Iridoid glycosides of Leonurus persicus.

Two new iridoid glucosides, 6-O-acetylajugol (1) and 7, 8-epoxy-8-epi-loganic acid (2), together with five known iridoid glucosides, galiridoside (3), ajugoside (4), 10-deoxygeniposidic acid (5), 7-deoxy-8-epi-loganic acid (6), and 8-O-acetylharpagide (7), have been isolated from the aerial parts of Leonurus persicus. Leucosceptoside A (8), eugenyl beta-rutinoside (9), and kaempferol 3-O-glucoside (10) were also isolated. The structures of 1 and 2 were elucidated by extensive 1D- and 2D-NMR spectroscopy and molecular modeling. The structure of 3 was confirmed by single-crystal X-ray diffraction. Antimicrobial activity of compounds (1-10) was also evaluated against a panel of gram-positive and gram-negative bacteria and two strains of fungi.     

Steroidal glycosides from the leaves of Cestrum nocturnum

Further phytochemical analysis aimed at the steroidal glycoside constituents of the leaves of Cestrum nocturnum has resulted in the isolation of eight new steroidal glycosides (1-8), which were classified into a spirostanol saponin (1), a furostanol saponin (2), a pseudo-furostanol saponin (3), two pregnane glycosides (4, 5), two cholestane glycosides (6, 7), and pregnane-carboxylic acid gamma-lactone glycoside (8), and of two known spirostanol glycosides (9, 10). The structures of the new compounds were elucidated on the basis of chemical and spectroscopic evidence.     

Flavonol glycosides from cassia hirsuta

A new flavonol glycoside, kaempferol 3-O-alpha-L-rhamnopyranosyl (1-->2)-alpha-L-rhamnopyranoside (1), was isolated from the flowers of Cassia hirsuta along with two known flavonol glycosides, kaempferol 3-O-rutinoside and rutin. The structure of compound 1 has been established on the basis of spectral data and by acid hydrolysis.     

Tetrasaccharide multi-esters and xanthone glycosides from the roots of Polygala wattersii

Ten new tetrasaccharide multi-esters, watteroses A-J (1-10), and two new xanthone glycosides, wattersiixanthones A (11) and B (12), were isolated from the roots of Polygala wattersii, together with 11 known compounds (10 oligosaccharide multi-esters and a xanthone glycoside). The structures of new compounds were elucidated on the basis of chemical and spectroscopic evidence.     

Glycosides from the bark of Adina polycephala

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.     

Seven new sesquiterpene glycosides from the root bark of Dictamnus dasycarpus

From the water-soluble constituents of the root bark of Dictamnus dasycarpus, six new eudesmane-type sesquiterpene glycosides, dictamnosides H-M (1-6), and a new trinorguaiane-type sesquiterpene glycoside, dictamnoside N (7), together with four known sesquiterpene glycosides, dictamnosides A (8), B (9), D (10), and G (11), were isolated. Their structures were elucidated by spectroscopic analyses and chemical evidence. In vitro tests for immunological activity showed dictamnoside A (8) to possess remarkable activity in stimulating the proliferation of T-cells.     

Anti-inflammatory and potential cancer chemopreventive constituents of the fruits of Morinda citrifolia (Noni)

A new anthraquinone, 1,5,15-tri-O-methylmorindol (1), and two new saccharide fatty acid esters, 2-O-(beta-D-glucopyranosyl)-1-O-hexanoyl-beta-D-gluropyranose (4) and 2-O-(beta-D-glucopyranosyl)-1-O-octanoyl-beta-D-gluropyranose (5), have been isolated from a methanol extract of the fruits of Morinda citrifolia (noni) along with 10 known compounds, namely, two anthraquinones (2, 3), six saccharide fatty acid esters (6-11), an iridoid glycoside (12), and a flavanol glycoside (13). Upon evaluation of six compounds (5-7, 9, 10, and 13) for inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 microg/ear) in mice, four saccharide fatty acid esters, 5-7 and 9, exhibited potent anti-inflammatory activity, with ID50 values of 0.46-0.79 mg per ear. In addition, when compounds 1-13 were evaluated against the Epstein-Barr virus early antigen (EBV-EA) activation induced by TPA, all of the compounds exhibited moderate inhibitory effects (IC50 values of 386-578 mol ratio/32 pmol TPA).     

管花肉苁蓉化学成分的研究

目的：研究国产管花肉苁蓉的化学成分。方法：采用各种色谱技术包括HPLC分离化学成分,根据理化性质和波谱数据鉴定结构。结果：分离得到4个环烯醚萜苷、1个木脂素苷和1个单萜,分别为五福花苷酸(Ⅰ),8-表马钱子酸(Ⅱ),京尼平苷酸(Ⅲ),玉叶金花苷酸(Ⅳ),丁香树脂酚葡萄糖苷(Ⅴ)和8-羟基香叶醇(Ⅵ)。结论：化合物Ⅰ和Ⅵ为首次从本属植物中分离得到,化合物Ⅲ,Ⅳ和Ⅴ为首次从本植物中分离得到。