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.     

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.     

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.     

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.     

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.     

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.     

Absolute configuration determination of angular dihydrocoumarins from Peucedanum praeruptorum

From Peucedanum praeruptorum, one new khellactone ester (3'R)-O-acetyl-(4'S)-O-angeloylkhellactone (3), as well as four known angular dihydropyranocoumarins (1, 2, 4, 5) have been isolated. On the basis of NMR spectra and X-ray crystallography, their structures were determined. We have elucidated their absolute configuration by either chiral separation of their alkaline hydrolysis products with Rp-18 HPLC eluted with 5% hydroxypropyl-β-cyclodextrin (β-HCD) or by measurement of their CD spectra. A general rule relating the position and absolute stereochemistry of the khellactone esters to the sign of their Cotton effects in CD curves is proposed.     

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).     

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.     

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.     

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).     

ent-Kaurenoids from the roots of Cacalia pilgeriana

Two new ent-kaurenoids,19-acetoxyl-ent-3β,17-dihydroxykaur-15-ene (1), 19-acetoxyl-ent-3β-hydroxykaur-15-en-17-al (2), together with seven known ent-kaurenoids: ent-kaur-16-en-19-al (3), ent-kaur-16-en-19-oic acid (4), ent-kauran-16β,17-diol (5), ent-15β, 16β-epoxy-17-hydroxykauran-19-oic acid (6),19-acetyl-ent-3β-hydroxyl-kaur-16-ene (7), ent-3β,19-dihydroxykaur-16-ene (8), ent-17-hydroxykaur-15-ene (9), were isolated from Cacalia pilgeriana. Their structures were elucidated by spectroscopic methods including 2D NMR spectral analysis.     

Structural elucidation of fritillahupehin from bulbs of Fritillaria hupehensis Hsiao et K.C. Hsia

A novel diterpenoid ester, fritillahupehin (1) and three known fatty acids, palmitic acid (2), lignoceric acid (3) and azelaric acid (4), have been isolated from the bulbs of Fritillaria hupehensis Hsiao et K.C. Hsia. The structure of fritillahupehin has been established to be ent-kauran-16β-yl lignocerate by means of spectroscopic and chemical evidence. Compounds 2-4 were isolated from Fritillaria sp. for the first time.     

A New Bicoumarin from Stellera Chamaejasme L

Thirteen compounds were isolated from roots of Stellera chamaejasme L. (Thymelaeaceae). They are β-sitosterol (2), simplexin (3), pimelea factor P2 (4), daucosterol (5), (+)-3-hydroxy-1,5-diphenyl-1-pentanone (6), 4-ethoxy-benzoic acid (7), 2,4,6-Trimethoxy-benzoic acid (8), (+)-afzelechin (9), fumaric acid (10), N,N-dimethyl-L-aspartic acid (11), umbelliferone (12), daphniretin (13) and a novel bicoumarin named bicoumastechamin (1). Among the known compounds, 7, 8, 9, 10 and 11 were first isolated from this plant, and 6 was first isolated from the natural resources. Their structures have been elucidated on the basis of spectral data. In vitro bioassays showed that 4 inhibited cancer cell growth, 13 exhibited immunomodulatory activity, and 6 exhibited both immunomodulatory and anti-tumor activity.     

Glycosyl flavonoids from the roots and rhizomes of Asarum longerhizomatosum

Two new glycosyl flavonoids including a glycosyl aurone, together with six known flavonoids were isolated from the roots and rhizomes of Asarum longerhizomatosum. The structures of the two new compounds were elucidated as 4,6,4'-trihydroxy-aurone-4,6-di-O-β-D-glucopyranoside (7, caulesauroneside) and naringenin-7,4'-di-O-β-D-glucopyranoside (8, caulesnarinside). The six known flavonoids were identified as naringenin (1), naringenin-5-O-β-D-glucopyranoside (2), naringenin-7-O- β-D-glucopyranoside (3), chalcononaringenin-2'-O-β-D-glucopyranoside (4), naringenin-5,7-di-O-β-D-glucopyranoside (5), chalcononaringenin-2',4'-di-O-β-D-glucopyranoside (6), respectively. This is the first report of the isolation of aurones in the family Aristolochiaceae.     

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.     

Two new lanostane triterpenoids from Poria cocos

Two new lanostane triterpenoids, 29-hydroxypolyporenic acid C (4) and 25-hydroxypachymic acid (5), together with three known compounds, ergosta-7,22-dien-3β-ol (1), polyporenic acid C (2) and pachymic acid (3), were isolated from the 95% ethanolic extract of the sclerotium of Poria cocos (Schw.) Wolf. Their structures were determined by extensive spectroscopic analyses, including IR, UV, ESITOF-MS, HRESI-MS, 1D and 2D NMR data (¹H NMR, ¹³C NMR, ¹H-¹H COSY, NOESY, HSQC and HMBC).     

A new anti-HIV lupane acid from Gleditsia sinensis Lam.

A new lupane acid, 2β-carboxyl,3β-hydroxyl-norlupA (1)-20 (29)-en-28-oic acid (1), together with five known lupane acid derivatives (2-6), were isolated from the stings of Gleditsia sinensis Lam.. Their structures were elucidated on the basis of 1D and 2D NMR techniques. All these known compounds were isolated from this genus for the first time. The new compound 1 showed strong anti-HIV activity.     

Triterpenoid saponins from Vaccaria segetalis

A new triterpenoid saponin, named segetoside C (1), and two known saponins, vaccaroid A (vaccaroside A) (2) and dianoside G (3), have been isolated from the seeds of Vaccaria segetalis. On the basis of chemical reaction and spectral data, the structure of segetoside C (1) has been established as: gypsogenic acid-28-O-[β-D-glucopyranosyl-(1 → 3)]-[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranoside.