Further flavonol and iridoid glycosides from Ajuga remota aerial parts

Five new iridoid glycosides characterised as 6-keto-8-acetylharpagide (1), 6,7-dehydro-8-acetylharpagide (2), 7,8-dehydroharpagide (3), 8-acetylharpagide-6-O-β-glucoside (4), harpagide-6-O-β-glucoside (5) together with three flavonol glycosides, myricetin 3-O-rutinoside-4'-O-rutinoside (6), myricetin 3-O-rutinoside-3'-O-rutinoside (7) and isorhamnetin 3-O-rutinoside-7-O-rutinoside-4'-O-β-glucoside (8) have been isolated from the aerial parts of Ajuga remota. Also isolated were two known compounds ajugarin IV and ajugarin V. Their structures were established using spectroscopic methods including UV, IR, FAB-MS, HR-MS, 1D and 2D NMR techniques.     

Sesquiterpene glucosides from anti-leukotriene B4 release fraction of Taraxacum officinale

Chemical examination of the MeOH extract of the root of Taraxacum officinale, which exhibited inhibitory activity on the formation of leukotriene B₄ from activated human neutrophils, has resulted in the isolation of 14-O-β-D-glucosyl-11,13-dihydro-taraxinic acid (1) and 14-O-β-D-glucosyl-taraxinic acid (2). The absolute stereostructure of 1 has been established by X-ray chrystallographic examination.     

Stilbene C-glucosides from Cissus repens

Four new stilbene C-glucosides, namely trans-3-O-methyl-resveratrol-2-C-β-glucoside (1), cis-3-O-methyl-resveratrol-2-C-β-glucoside (2), trans-3-O-methyl-resveratrol-2-(2-p-coumaric)-C-β-glucoside (cissuside A) (3), and trans-3-O-methyl-resveratrol-2-(3-p-coumaric)-C-β-glucoside (cissuside B) (4), were isolated from the aerial parts of Cissus repens, along with known trans-resveratrol (5), trans-resveratrol-2-C-β-glucoside (6) and cis-resveratrol-2-C-β-glucoside (7). Their structures were established by spectroscopic methods. Stilbene C-glucosides were found in the genus Cissus for the first time.     

Arylglycerol glucosides from Dracocephalum forrestii

Three new arylglycerol glucosides, threo-guaiacylglycerol 3-O-(6-O-p-hydroxybenzoyl)-β-D-glucopyranoside (1), threo-guaiacylglycerol 3-O-[6-O-(E)-p-coumaroyl]-β-D-glucopyranoside (2) and threo-guaiacylglycerol 3-O-[6-O-(Z)-p-coumaroyl]-β-D-glucopyranoside (3), together with seven known compounds were isolated from the whole plants of Dracocephalum forrestii and their structures were determined on the basis of spectroscopic evidences.     

Studies on chemical constituents from Ilex pubescens

Two new phenolic glycosides, ilexpubsides A and B, along with four known lignan glycosides were isolated from the roots of Ilex pubescens. By spectral evidence, the structures of the new compounds were elucidated as 4-O-β-D-[6'-O-(4'-O-β-D-glucopyranosylvanilloyl)glucopyranosyl] vanillic acid (1) and syringinic 6'-O-β-D-xylopyranoside (2). The known compounds were identified to be liriodendrin (3), (-)-olivil (4), tortoside A (5) and (+)-cyclo-olivil (6). All compounds were first isolated from Ilex pubescens.     

Chemical Constituents from the Leaves of Magnolia Denudata

20 compounds were isolated from the leaves of Magnolia denudata including 16 lignans, which belong to 6 structural types. Except for (7R, 8S, 1'S) -δ^8' - 1', 4' - dihydro - 5'- methoxy - 3, 4 -methylenedioxy - 4' - oxo -7.O.2', 8.1' - neolignan (6), magliflonenone (9), 2,5' - diene-2', 8'- epoxy - 5' - methoxy - 8 - methyl - 4' - oxo - 3,4-methylenedioxy - spiro (5,5) - undecane (10), veraguensin (16) and β-sitosterol (20), the other 15 compounds were obtained from this species for the first time. The absolute configurations of 3 compounds (1,4,10) were determined by CD spectroscopy for the first time. The anti-inflammatory activities of compounds 1, 2 and 16 were assessed and 2 was shown to have significant inhibition effect on mice hind-paw edema induced by carrageenan.     

Three new norlignans from Curculigo capitulata

From the ethanolic extract of the rhizomes of Curculigo capitulata have been isolated, and structurally elucidated by spectral evidences and chemical methods, three new norlignans, capituloside (1), a mixture of curculigenin (2) and isocurculigenin (3), along with four known compounds (4-7), a mixture of 1-O-methylcurculigine (4) and 1-O-methylisocurculigine (5) and a mixture of curculigine (6) and isocurculigine (7).     

A new diterpene from the processed roots of Euphorbia Kansui

A new diterpene has been isolated from the processed roots of Euphorbia Kansui. By means of physico-chemical evidences and spectral analysis, the structure was identified as 4-O-acetyl-5-O-benzoyl-3β-hydroxy-20-deoxyingenol (1).     

Antioxidant phenolic glucosides from Gentiana piasezkii

An extract of Gentiana piasezkii afforded a new arbutin derivative 6'-O-vanilloylarbutin (1) and a new flavone-C-glucoside 7-O-feruloylorientin (2), together with four known flavonoids lutonarin (3), saponarin (4), isoorient (5) and luteolin (6). Their structures were established based on spectroscopic methods including 2D NMR (COSY and gHMBC) techniques. Compounds 1, 2, 5 and 6 were evaluated for the antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay system.     

Isolation and identification of a novel flavonoid from Penthorum chinense P

A novel flavonoid, pinocembrin-7-O-[3'-O-galloyl-4',6'-hexahydroxydiphenoyl]-β-glucose (1) was isolated from the whole plant of Penthorum chinense P., along with four known compounds, pinocembrin-7-O-β-glucoside, quercitrin, quercetin-3-O-rhamnoside and gallic acid. The structures were established by spectroscopic analysis.     

Ether-soluble resin glycosides from the roots of Ipomoea batatas

Two new resin glycosides, batataosides I (1) and II (2), and five known compounds, friedelin (3), scopoletin (4), octadecyl caffeate (5), β-sistosterol (6) and daucosterol (7), were isolated from the roots of Ipomoea batatas. Their structures have been determined based on the chemical and spectral data. Batataosides I and II have novel structures because the core simonic acid B was esterised with cinnamic acid for the first time, and three different substituent esterification groups in one resin glycoside is scarce. The absolute configuration of the aglycone was elucidated to be S by Mosher's method.     

Microbial hydroxylation of cinobufagin by Mucor spinosus

Mucor spinosus has been employed for the biotransformation of cinobufagin (1) to afford three metabolites. On the basis of their physico-chemical data, the structures of the transformation products have been characterized as 1β-hydroxy-cinobufagin (2), 12β-hydroxy-cinobufagin (3) and 1β,12β-dihydroxy-cinobufagin (4), of which metabolites 2 and 4 are new compounds. In vitro cytotoxic activities of the biotransformation products and the substrate-cinobufagin have been assayed against four tumor cell lines of Bel 7420, BGC 823, HeLa and HL 60; they all showed cytotoxic activities.     

A new sesquiterpene lactone glucoside with inhibitory effect on K562 cells from Ixeris sonchifolia (Bge) Hance

A new minor sesquiterpene lactone glucoside, ixerin Z_A (1), together with 16 known compounds, were isolated from the whole plants of Ixeris sonchifolia (Bge) Hance. The structure of 1 was elucidated as 1(10),3,11(13)-guaiatriene-12,6-olide-2-one-3-O-[6'-(p-metheoxyphenylacetyl)]-β-glucopyranoside on the basis of spectroscopic and chemical evidence. Compound 1 exhibited an inhibitory effect on K₅₆₂ cells.     

Antibacterial constituents from Stemona sessilifolia

Bioassay-guided fractionation led to the isolation of eight compounds from Stemona sessilifolia. Of the eight isolates, three new bibenzyls, stilbostemins M-O (1-3), and a new tocopherol, 6-methoxy-3,4-dehydro-δ-tocopherol (4) were revealed together with four known compounds 3,5-dihydroxy-2'-methoxy bibenzyl (5), 3,5-dihydroxy bibenzyl (6), β-tocopherol (7), and γ-tocopherol (8). Compounds 5, 6, and 8 exhibited strong antibacterial activities against Staphylococcus aureus and S. epidermidis.     

Pyrrolizidine alkaloids from Cynoglossum furcatum

Two new pyrrolizidine alkaloids have been isolated from the roots of Cynoglossum furcatum. On the basis of chemical and spectroscopic evidence, structures of the compounds have been elucidated. They are lactodine (3), a monoster alkaloid and viridinatine (4), a pyrrolizidine diester alkaloid. The structure of lactodine is elucidated as 9-O-(-)lactyl heliotridine and viridinatine as 7-O-(-)viridifloryl echinatine.     

A new dicoumarinoid glycoside from Daphne giraldii

A new dicoumarinoid glycoside, named giraldoid A (1), has been isolated from Daphne giraldii Nitsche. The structure of 1 was determined as 7-O-β-glucosyl-8-(7-hydroxy-2H-1-benzopyran-2-one-8-)yl-2H-1-benzopyran-2-one on the basis of chemical reactions and spectroscopic methods.     

Studies on the alkaloid constituents of Evodia rutaecarpa (Juss) Benth var. bodinaieri (Dode) Huang and their acute toxicity in mice

Six alkaloids (1-6) have been isolated from the fruits of Evodia rutaecarpa (Juss) Benth var. bodinaieri (Dode) Huang, two of which are new compounds, identified as 2-undecyl-4(1H)-quinolone (4) and 1-methyl-2-undecanone-10'-4(1H)-quinolone (5); the known compounds were identified as rutaecarpine (1), evodiamine (2), 1-methyl-2-undecyl-4(1H)-quinoline (3) and 2-undecanone-10'-4(1H)-quinolone (6). Compounds 1-5 were evaluated for their acute toxicity.     

Chemical constituents of Pseudopterogorgia species of the Indian ocean

A new ceramide, (2S,3R,4E)-1,3-dihydroxy-2-[(hexadecanoyl)amino]-nonadeca-4-ene (1), cholest-5-en-3β,7β,19-triol (2), identified as its, peracetyl derivative (3), and batyl alcohol (4) were isolated from Pseudopterogorgia species. 1 exhibited antibacterial activity against Gram-positive and Gram-negative bacteria.     

Three new isoprenylated flavonoids from the roots of Sophora flavescens

Three new flavonoids isoprenylated as 2,2-dimethyl-dihydropyran groups, named sophoranodichromanes A-C (1-3), have been isolated from the roots of Sophora flavescens, together with the known compounds, chrysophanol (4), soyasapogenol B (5) and β-sitosterol (6). Their structures have been elucidated by spectroscopic methods.     

Two new and four known polyphenolics obtained as new cell-cycle inhibitors from Rubus aleaefolius Poir

Two new polyphenolics, rubuphenol (1) and sanguiin H-2 ethyl ester (2), were isolated together with ellagic acid (3), ethyl gallate (4), 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (5) and 1,2,3,6-tetra-O-galloyl-β-D-glucopyranose (6) as new cell-cycle inhibitors from Rubus aleaefolius by bioassay-guided separation procedure and the structures of 1 and 2 were elucidated by spectroscopic method. Compounds 1 - 6 inhibited the cell cycle progression of tsFT210 cells at the G₀/G₁ phase with the MIC values of 14.6 μM (1), 22.1 μM (2), 10.3 μM (3), 7.8 μM (4), 7.9 μM (5) and 6.6 μM (6).