Isoflavone diglycosides from Glycosmis pentaphylla

Six new apiosyl-(1-->6)-glucosyl isoflavones (1-6) and four known ones were isolated from the stems of Glycosmis pentaphylla. The structures of the new glycosides are 3',7-dihydroxy-4',5,6-trimethoxyisoflavone 7-O-(5-O-trans-p-coumaroyl)-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (1), 2',7-dihydroxy-4',5',5,6-tetramethoxyisoflavone 7-O-(5-O-trans-p-coumaroyl)-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (2), 2',7-dihydroxy-4',5',5,6-tetramethoxyisoflavone 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (3), 7-hydroxy-4',8-dimethoxyisoflavone 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (4), 7-hydroxy-4',6-dimethoxyisoflavone 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (5), and 4',5-dihydroxy-3',7-dimethoxyisoflavone 4'-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (6). Their structures were established primarily by NMR experiments and chemical methods.     

Phenylvaleric acid and flavonoid glycosides from Polygonum salicifolium.

(3R)-O-beta-D-Glucopyranosyloxy-5-phenylvaleric acid (1), (3R)-O-beta-D-glucopyranosyloxy-5-phenylvaleric acid n-butyl ester (2), and a new dihydrochalcone diglycoside 4'-O-[beta-D-glucopyranosyl-(1-->6)-glucopyranosyl]oxy-2'-hydroxy-3', 6'-dimethoxydihydrochalcone (3), together with six known flavonoid glycosides [kaempferol-3-O-beta-D-glucopyranoside (= astragalin) (4), kaempferol-3-O-beta-D-galactopyranoside (5), quercetin-3-O-beta-D-glucopyranoside (= isoquercitrin) (6), quercetin-3-O-beta-D-galactopyranoside (= hyperoside) (7), quercetin-3-O-(2'-O-galloyl)-beta-D-glucopyranoside (8), and quercetin-3-O-beta-D-glucuronopyranoside (9)] were isolated from the aerial parts of Polygonum salicifolium. The structure elucidation of the isolated compounds was performed by spectroscopic (UV, IR, ESI-MS, 1D- and 2D-NMR), chemical (methylation, enzymatic hydrolysis, partial synthesis), and chromatographic methods (HPLC, Chiralcel OD). The flavonoid glycosides (4-9) demonstrated scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical in TLC autographic assays.     

Phenolic glycosides from Viscum angulatum

Three new glycosides, pinocembrin 7-O-apiosyl(1-->5)apiosyl(1-->2)-beta-D-glucopyranoside (1), 2',3',4',3' '-tetramethoxy-1,3-diphenylpropane 5',4' '-di-O-beta-D-glucopyranoside (2), and rhamnocitrin 3-O-apiosyl(1-->5)apiosyl(1-->2)-[alpha-L-rhamnopyranosyl(1-->6)]-beta-D-glucopyranoside (3), were isolated from Viscum angulatumalong with viscumneoside V, naringenin, and homoeriodictyol. Their structures were established by spectral and chemical methods.     

Phenolic constituents and antioxidant activity of an extract of Anthuriumversicolor leaves

Fractionation of a methanolic extract of the leaves of Anthurium versicolor has resulted in the isolation of two main fractions, I and II. Both the extract and the fractions were assayed for their radical-scavenging activity by means of an in vitro test (bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical) and showed a significant radical-scavenging effect. Subsequent chromatographic fractionation of the most active fraction, II, has led to the isolation and characterization, as major constituents, of four new flavone glycosides, acacetin 6-C-[alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranoside] (1), acacetin 6-C-[beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside] (2), acacetin 6-C-[beta-D-apiofuranosyl-(1-->3)-beta-D-glucopyranoside] (3), and acacetin 8-C-[alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranoside] (4), as well as vitexin (apigenin-8-C-beta-D-glucopyranoside) and rosmarinic acid. The structures of 1-4 were determined using spectroscopic methods.     

Inhibitors of osteoclast differentiation from Cephalotaxus koreana

Three new flavonoid glycosides ( 1- 3), 11-hydroxyhainanolidol ( 4), and a new dibenzylbutyrolactone lignan glycoside ( 5) were isolated from the aerial parts of Cephalotaxus koreana Nakai, along with 19 known flavonoids. The structures of the new compounds were elucidated using spectroscopic evidence, primarily NMR and MS. Twenty-four compounds were isolated, and among these isoscutellarein 5-O-beta-D-glucopyranoside ( 3), apigenin ( 6), kaempferol 3-O-alpha-L-rhamnopyranosyl(1'-->6')-beta-D-glucopyranoside ( 7), tamarixetin 3-O-alpha-L-rhamnopyranosyl(1'-->6')-beta-D-glucopyranoside ( 8), quercetin 3-O-[6'-O-acetyl]-beta-D-glucopyranoside ( 9), and quercetin 3-O-alpha-L-rhamnopyranoside ( 10) showed significant inhibitory activities against osteoclast differentiation at concentrations of 0.1 and 1.0 microg/mL.     

Two new spirostanol saponins from Allium tuberosum.

Two new spirostanol saponins, tuberosides D and E, have been isolated from the seeds of Allium tuberosum. On the basis of spectral data and chemical reactions, their structures were established as (25S)-5alpha-spirostane-2alpha,3beta-diol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4 )]-O-beta-D-glucopyranoside and (25S)-5alpha-spirostan-2alpha, 3beta-diol 3-O-beta-D-glucopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)] -O-beta-D-glucopyranoside, respectively.     

Neuroprotective constituents from Hedyotis diffusa

In a bioassay-guided search for neuroprotective compounds from medicinal plants, a MeOH extract of whole plants of Hedoytis diffusa yielded five flavonol glycosides, kaempferol 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-galactopyranoside (1), quercetin 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-galactopyranoside (2), quercetin 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-glucopyranoside (3), kaempferol 3-O-(2-O-beta-D-glucopyranosyl)-beta-D-galactopyranoside (4), and quercetin 3-O-(2-O-beta-D-glucopyranosyl)-beta-D-galactopyranoside (5), and four O-acylated iridoid glycosides (6-9). Compounds 1 and 2 are previously unreported natural products, and all nine compounds exhibited significant neuroprotective activity in primary cultures of rat cortical cells damaged by L-glutamate.     

A new pregnane glycoside from Dioscorea collettii var. hypoglauca

During further bioactivity-guided fractionation, a new pregnane glycoside, hypoglaucin G (1), and a known compound, pregna-5, 16-dien-3beta-ol-20-one 3-O-alpha-L-rhamnopyranosyl-(1-->2)- [alpha-L-rhamnopyranosyl-(1-->4)] -beta-D-glucopyranoside (2), were isolated from the EtOH extract of Dioscorea collettii var. hypoglauca rhizomes, which induced morphological deformation of Pyricularia oryzae mycelia with minimum morphological deformation concentration values of 135 microM and 236 microM, respectively. The structure of 1 was established as 16beta-(4'-methyl-5'-O-beta-D-glucopyranosyl- pentanoxyl)-pre gn-5-en-3 beta-ol-20-one 3-O-alpha-L- rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D- glucopyranoside on the basis of chemical evidence and spectral analysis, especially by 2D NMR techniques.     

Bioactive compounds from the seeds of Punica granatum (pomegranate)

Two new compounds, coniferyl 9-O-[beta-D-apiofuranosyl(1-->6)]-O-beta-D-glucopyranoside (1) and sinapyl 9-O-[beta-d-apiofuranosyl(1-->6)]-O-beta-D-glucopyranoside (2), were isolated from the seeds of Punica granatum (pomegranate), together with five known compounds, 3,3'-di-O-methylellagic acid (3), 3,3',4'-tri-O-methylellagic acid (4), phenethyl rutinoside, icariside D1, and daucosterol. The structures of 1 and 2 were elucidated by spectroscopic data analysis. Compounds 1-4 exhibited antioxidant activity, which was evaluated by measurement of low-density lipoprotein (LDL) susceptibility to oxidation and by determination in vitro of malondialdehyde (MDA) levels in the rat brain.     

Kinmoonosides A-C, three new cytotoxic saponins from the fruits of Acacia concinna, a medicinal plant collected in myanmar

Three genuine saponins, named kinmoonosides A-C (1-3), have been isolated, together with a new monoterpenoid (4), from a methanolic extract of the fruits of Acacia concinna. The structures of kinmoonosides A-C were elucidated on the basis of spectral analysis as 3-O-?alpha-L-arabinopyranosyl(1-->6)-[beta-D-glucopyranosyl(1-->2) ]-b eta-D-glucopyranosyl?-21-O-?(6R, 2E)-2-hydroxymethyl-6-methyl-6-O-[4-O-(2'E)-6'-hydroxyl-2'-hydroxymet hyl-6'-methyl-2',7'-octadienoyl-beta-D-quinovopyranosyl]-2, 7-octadienoyl?acacic acid 28-O-alpha-L-arabinofuranosyl(1-->4)-[beta-D-glucopyranosyl(1-->3)]-a lpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl ester (1); 3-O-?alpha-L-arabinopyranosyl(1-->6)-[beta-D-glucopyranosyl(1-->2) ]-b eta-D-glucopyranosyl?-21-O-?(6S, 2E)-2-hydroxymethyl-6-methyl-6-O-[4-O-(2'E)-6'-hydroxyl-2'-hydroxymet hyl-6'-methyl-2',7'-octadienoyl-beta-D-quinobopyranosyl]-2, 7-octadienoyl?acacic acid 28-O-alpha-L-arabinofuranosyl(1-->4)-[beta-D-glucopyranosyl(1-->3)]-a lpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl ester (2); and 3-O-?alpha-L-arabinopyranosyl(1-->6)-[beta-D-glucopyranosyl(1-->2) ]-b eta-D-glucopyranosyl?-21-O-[(2E)-6-hydroxyl-2-hydroxymethyl-6-methyl- 2,7-octadienoyl]acacic acid 28-O-alpha-L-arabinofuranosyl(1-->4)-[beta-D-glucopyranosyl(1-->3)]-a lpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl ester (3), respectively. The new monoterpenoid 4 was determined as 4-O-[(2E)-6-hydroxyl-2-hydroxymethyl-6-methyl-2, 7-octadienoyl]-D-quinovopyranose. Compounds 1-3 showed significant cytotoxicity against human HT-1080 fibrosarcoma cells.     

Trypanocidal withanolides and withanolide glycosides from Dunalia brachyacantha.

Two new withanolide glycosides, (20R,22R)-O-(3)-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl-1 alpha,12 beta-diacetoxy-20-hydroxywitha-5,24-dienolide (3) and (20R,22R)-O-(3)-beta-D-xylopyranosyl(1-->3)-[beta-D-xylopyranosyl(1-->4)]-beta-D-glucopyranosyl-1 alpha-acetoxy-12 beta,20-dihydroxywitha-5,24-dienolide (4), were isolated from the leaves and root of Dunalia brachyacantha. Their aglycones, (20R,22R)-1 alpha,12 beta-diacetoxy-3 beta,20-dihydroxywitha-5,24-dienolide (or 1 alpha,12 beta-diacetyldunawithagenine) and (20R,22R)-1 alpha-acetoxy-3 beta,12 beta,20-trihydroxywitha-5,24-dienolide (or 1 alpha-acetyl-12 beta-hydroxydunawithagenine), are novel. The known 18-acetoxywithanolide D (1) and 18-acetoxy-5,6-deoxy-5-withenolide D (2) were also isolated from the leaves. These last two compounds were shown to be responsible for the trypanocidal, leishmanicidal, and bactericidal activities manifested by the crude ethanolic extract. The structures were deduced from spectroscopic data and on the basis of chemical evidence.     

New steroidal glycosides from the fruits of Tribulus terrestris

Three new steroidal saponins (1-3) were isolated from the fruits of Tribulus terrestris. Their structures were assigned by spectroscopic methods (IR, HRESIMS, 1D- and 2D-NMR) as 26-O-beta-D-glucopyranosyl-(25S)-5beta-furost-20(22)-en-3bet a, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl- (1-->4)]-beta-D-glucopyranoside (1), 26-O-beta-D-glucopyranosyl-(25S)-5beta-furost-20(22)-en-3bet a, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1 -->4)]-beta-D-galactopyranoside (2), and 25(S)-5beta-spirostan-3beta-ol-3-O-alpha-L-rhamnopyranosyl-( 1-->2)-[b eta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside (3). Compound 3 showed cytotoxicity against a human malignant melanoma cell line (SK-MEL).     

New lignan glycosides with potent antiinflammatory effect, isolated from Justicia ciliata

Two new lignan glycosides, 4-O-[alpha-L-arabinopyranosyl-(1' "-->2' ')-beta-D-xylopyranosyl-(1' " '-->5' ')-beta-D-apiofuranosyl]diphyllin (1), named ciliatoside A (1), and 4-O-?[beta-D-apiofuranosyl-(1' " "-->3' ")-alpha-L-arabinopyranosyl-(1' "-->2' ')][beta-D-xylopyranosyl-(1' " '-->5' ')]-beta-D-apiofuranosyl?diphyllin (2), named ciliatoside B (2), were isolated from the whole plant of Justicia ciliata. The structures of 1 and 2 were determined by spectral and chemical methods. Compounds 1 and 2 strongly inhibited the accumulation of NO(2)(-) in lipopolysaccharide-stimulated RAW 264.7 cells in a concentration-dependent manner with IC(50) values of 27.1 +/- 1.6 and 29.4 +/- 1.4 microM, respectively.     

Five new triterpene saponins from Pulsatilla patens var. multifida

Five new oleanane-type glycosides (1-5), along with two known triterpene saponins, were isolated from the roots of Pulsatilla patens var. multifida (Ranunculaceae). The structures of the new triterpene saponins were elucidated as 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (1), hederagenin 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranoside (2), 3-O-beta-D-glucopyranosyl bayogenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (3), 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (4), and 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (5). Structure elucidation was accomplished by 1D and 2D NMR (HMQC, HMBC, and ROESY) methods, FABMS, and hydrolysis.     

Phenolic glycosides from berries of Pimenta dioica

Four new phenolic glycosides, (2-hydroxy-3-methoxy-5-allyl)phenyl beta- d-(6-O-E-sinapoyl)glucopyranoside (1), (1' R,5' R)-5-(5-carboxymethyl-2-oxocyclopentyl)-3 Z-pentenyl beta-D-(6-O-galloyl)glucopyranoside (2), (S)-alpha-terpinyl [alpha-L-(2-O-galloyl)arabinofuranosyl]-(1-->6)-beta-D-glucopyranoside (3), and (R)-alpha-terpinyl [alpha-L-(2-O-galloyl)arabinofuranosyl]-(1-->6)-beta-D-glucopyranoside (4), were isolated from the berries of Pimenta dioica together with eight known flavonoids. The structures of 1-4 were elucidated on the basis of MS and NMR data and enzymatic hydrolysis. All four glycosides showed radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals.     

Phenolic compounds from Miconia myriantha inhibiting Candida aspartic proteases.

Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia myriantha yielded two new compounds, mattucinol-7-O-[4' ',6' '-O-(S)-hexahydroxydiphenoyl]-beta-D-glucopyranoside (1) and mattucinol-7-O-[4' ',6' '-di-O-galloyl]-beta-D-glucopyranoside (2), along with mattucinol-7-O-beta-D-glucopyranoside (3), ellagic acid (4), 3,3'-di-O-methyl ellagic acid-4-O-beta-D-xylopyranoside, and gallic acid. Complete (1)H and (13)C NMR assignments of compound 1, which possesses a hexahydroxydiphenoyl unit, were achieved using the HMBC technique optimized for small couplings to enhance the four-bond and two-bond H/C correlations. Compounds 1 and 4 showed inhibitory effects against Candida albicans secreted aspartic proteases, with IC(50) of 8.4 and 10.5 microM, respectively.     

Saponarioside C, the first alpha-D-galactose containing triterpenoid saponin, and five related compounds from Saponaria officinalis

Six novel triterpenoid saponins, named saponariosides C-H, were isolated from the whole plants of Saponaria officinalis. Their structures were established as saponarioside C (1), 3-O-beta-D-xylopyranosyl-gypsogenic acid-28-O-alpha-D-galactopyranosyl-(1-->6)-beta-D-glucopyranosyl-(1-- >6)-[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranoside; saponarioside D (2), 3-O-beta-D-xylopyranosyl-gypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->6) -[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranoside; saponarioside E (3), 3-O-beta-D-glucopyranosyl-gypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->6) -[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranoside; saponarioside F (4), 3-O-beta-D-xylopyranosyl-16alpha-hydroxygypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->6) -[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranoside; saponarioside G (5), 3-O-beta-D-xylopyranosyl-16alpha-hydroxygypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->6)-[beta-D-glucopyranosyl-(1-->3 )]-beta-D-glucopyranoside; and saponarioside H (6), 3-O-beta-D-xylopyranosyl-gypsogenic acid-28-O-beta-D-glucopyranoside, by a combination of extensive NMR (DEPT, COSY, HOHAHA, HETCOR, HMBC, and NOESY) studies and chemical degradation.     

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.     

Isolation and structure of cytostatic steroidal saponins from the African medicinal plant Balanites aegyptica.

Bioactivity-guided separation of a CH2Cl2/MeOH extract of Balanites aegyptica afforded four new cytostatic saponins, named balanitins 4 [1], 5 [2], 6 [3], and 7 [4]. On the basis of enzymatic hydrolyses and glycosidation nmr chemical shifts employing the peracetates, structures 1-4 were established as yamogenin 3 beta-O-beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl-(1----4)-[al pha- L-rhamnopyranosyl-(1----2)]-beta-D-glucopyranoside [1], yamogenin 3 beta-O-alpha-L-rhamnopyranosyl-(1----3)-beta-D-glucopyranosyl-(1----4)- [alpha-L-rhamnopyranosyl-(1----2)]-beta-D-glucopyranoside [2], yamogenin 3 beta-O-beta-D-glucopyranosyl-(1----4)-[alpha-L- rhamnopyranosyl-(1----2)]-beta-D-glucopyranoside [3], and diosgenin 3 beta-O-beta-D-xylopyranosyl-(1----3)-beta-D-glucopyranosyl-(1----4)-[alp ha- L-rhamnopyranosyl-(1----2)]-beta-D-glucopyranoside [4].     

Antiprotozoal activity of the constituents of Conyza filaginoides

Bioassay-guided fractionation of the antiprotozoal extract of Conyza filaginoides led to the isolation of three new flavonol caffeoyl glycosides, namely, kaempferol 3-O-(6' '-O-E-caffeoyl)-beta-D-galactopyranoside (1), isorhamnetin 3-O-(6' '-O-E-caffeoyl)-beta-D-galactopyranoside (2), and quercetin 3-O-(6' '-O-E-caffeoyl)-beta-D-glucopyranoside (3). In addition, seven known compounds, erythrodiol (4), beta-caryophyllene-4,5-alpha-oxide (5), astragalin (6), isoquercitrin (7), nicotiflorin (8), narcissin (9), and rutin (10), were obtained. The structures of the new isolates were elucidated by spectroscopic and chemical methods. Compounds were also assessed for antiamoebic and antigiardial activities, but none was significantly active compared to the standard drugs evaluated.