Three new furostanol saponins from the leaves of Lycianthes synanthera ("Chomte"), an edible Mesoamerican plant

Three new furostanol oligoglycosides, 3-O-{alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl}-26-O-beta-D-glucopyranosyl-22alpha-methoxy-25R-furost-5-ene-3beta,17alpha,26-triol (1), 3-O-{alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl}-26-O-beta-D-glucopyranosylfurost-5-ene-3beta,17alpha,22alpha,25,26-pentol (2), and 3-O-{alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl}-26-O-beta-D-glucopyranosylfurost-5-ene-3beta,22alpha,25,26-tetrol (3), named lycianthosides A-C, together with known flavone glycosides were isolated from Lycianthes synanthera leaves, an edible plant of the Solanaceae family that grows naturally in Guatemala. The nutrient composition of the raw leaves was also evaluated.     

Antimicrobial furostanol saponins from the seeds of Capsicum annuum L. var. acuminatum

Three new furostanol saponins named capsicoside E (1), capsicoside F (2), and capsicoside G (5) were obtained from the seeds of Capsicum annuum L. var. acuminatum along with known oligoglycosides (3, 4, and 6-10). On the basis of chemical and spectroscopic analyses, the structures of these new furostanol oligoglycosides were elucidated as 26-O-beta-D-glucopyranosyl-22-O-methyl-5alpha-furost-25(27)-en-2alpha,3beta,22xi,26-tetraol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (1), 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furost-20(22)-en-2alpha,3beta,26-triol-3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (2), and 26-O-beta-D-gluco-pyranosyl-(25R)-5alpha-furosta-3beta,22xi,26-triol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (5). The isolated saponins showed higher antimicrobial activity against yeasts than against common fungi. Data indicated that the antiyeast activity was related to the combination of the oligosaccharide chain (S1, S2, or S3) with an O-methyl group at R(3) and the presence of a hydroxyl group at the C-2 position.     

Isolation and identification of steroidal saponins in Taiwanese yam cultivar (Dioscorea pseudojaponica Yamamoto)

A new furostanol pentaoligoside and spirostanol tetraoligoside were isolated for the first time from yam tubers (Dioscorea pseudojaponica Yamamoto) from Taiwan, together with four known yam saponins, methyl protodioscin, methyl protogracillin, dioscin, and gracillin. Their structures were characterized as 26-O-beta-D-glucopyranosyl-22alpha-methoxyl-(25R)-furost-5-en-3beta,26-diol, 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-([alpha-L-rhamnopyranosyl-(1-->4)]-O-[alpha-L-rhamnopyranosyl-(1-->4)])-beta-D-glucopyranoside, and (25R)-spirost-5-en-3beta-ol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-([alpha-L-rhamnopyranosyl-(1-->4)]-O-[alpha-L-rhamnopyranosyl-(1-->4)])-beta-D-glucopyranoside. The structural identification was performed using LC-MS and 1H and 13C NMR. The methanol extract of yam tubers was fractionated by XAD-2 column chromatography using a methanol/water gradient elution system to yield furostanol and spirostanol glycoside fractions. Preparative high-performance liquid chromatography, employing a C18 column and a mobile phase of methanol/water (69:31, v/v), was used to separate each furostanol glycoside, whereas a mobile phase of methanol/water (79:21, v/v) was used to resolve the individual spirostanol glycosides. The conversions from steroid saponins to diosgenin after acid hydrolysis were around 68 and 90% for furostanol and spirostanol glycosides, respectively.     

Chemical composition of shallot (Allium ascalonicum Hort.)

An extensive phytochemical analysis of the polar extracts from bulbs of shallot, Allium ascalonicum Hort., led to the isolation of two new furostanol saponins, named ascalonicoside A1/A2 (1a/1b) and ascalonicoside B (4), respectively, along with compounds 2a and 2b, most likely extraction artifacts. On the basis of 2D NMR and mass spectrometry data, the structures of the novel compounds were elucidated as furost-5(6)-en-3beta,22alpha-diol 1beta-O-beta-D-galactopyranosyl 26-O-[alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranoside] (1a), its epimer at position 22 (1b), and furost-5(6),20(22)-dien-3beta-ol 1beta-O-beta-D-galactopyranosyl 26-O-[alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranoside] (4). This is the first report of furostanol saponins in A. ascalonicum. High concentrations of quercetin, isorhamnetin, and their glycosides were also isolated and described.     

Four new steroidal saponins from the seeds of Allium tuberosum

Four new steroidal saponins, 26-O-beta-D-glucopyranosyl-(25S,20R)-20-O-methyl-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (1); 26-O-beta-D-glucopyranosyl-(25S,20R)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (2); 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (3); and 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-3beta,20,26-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (4), have been isolated from the seeds of Allium tuberosum. Their structures were established by spectroscopic studies such as MS, IR, NMR, and 2D-NMR and the results of acid hydrolysis and named tuberosides F, G, H, and I, respectively.     

New spirostanol saponins from Chinese chives (Allium tuberosum)

Three new spirostanol saponins have been isolated from the seeds of Allium tuberosum. On the basis of acid hydrolysis and comprehensive spectroscopic analysis, their structures were established as tuberoside J, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside; tuberoside K, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside; and tuberoside L, 27-O-beta-D-glucopyranosyl-(25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-D-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside.     

Quantitative analysis of steroidal glycosides in different organs of Easter lily (Lilium longiflorum Thunb.) by LC-MS/MS

The bulbs of the Easter lily ( Lilium longiflorum Thunb.) are regularly consumed in Asia as both food and medicine, and the beautiful white flowers are appreciated worldwide as an attractive ornamental. The Easter lily is a rich source of steroidal glycosides, a group of compounds that may be responsible for some of the traditional medicinal uses of lilies. Since the appearance of recent reports on the role steroidal glycosides in animal and human health, there is increasing interest in the concentration of these natural products in plant-derived foods. A LC-MS/MS method performed in multiple reaction monitoring (MRM) mode was used for the quantitative analysis of two steroidal glycoalkaloids and three furostanol saponins, in the different organs of L. longiflorum. The highest concentrations of the total five steroidal glycosides were 12.02 ± 0.36, 10.09 ± 0.23, and 9.36 ± 0.27 mg/g dry weight in flower buds, lower stems, and leaves, respectively. The highest concentrations of the two steroidal glycoalkaloids were 8.49 ± 0.3, 6.91 ± 0.22, and 5.83 ± 0.15 mg/g dry weight in flower buds, leaves, and bulbs, respectively. In contrast, the highest concentrations of the three furostanol saponins were 4.87 ± 0.13, 4.37 ± 0.07, and 3.53 ± 0.06 mg/g dry weight in lower stems, fleshy roots, and flower buds, respectively. The steroidal glycoalkaloids were detected in higher concentrations as compared to the furostanol saponins in all of the plant organs except the roots. The ratio of the steroidal glycoalkaloids to furostanol saponins was higher in the plant organs exposed to light and decreased in proportion from the aboveground organs to the underground organs. Additionally, histological staining of bulb scales revealed differential furostanol accumulation in the basal plate, bulb scale epidermal cells, and vascular bundles, with little or no staining in the mesophyll of the bulb scale. An understanding of the distribution of steroidal glycosides in the different organs of L. longiflorum is the first step in developing insight into the role these compounds play in plant biology and chemical ecology and aids in the development of extraction and purification methodologies for food, health, and industrial applications. In the present study, (22R,25R)-spirosol-5-en-3β-yl O-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranoside, (22R,25R)-spirosol-5-en-3β-yl O-α-l-rhamnopyranosyl-(1→2)-[6-O-acetyl-β-d-glucopyranosyl-(1→4)]-β-d-glucopyranoside, (25R)-26-O-(β-d-glucopyranosyl)furost-5-ene-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranoside, (25R)-26-O-(β-d-glucopyranosyl)furost-5-ene-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyl-(1→3)-β-d-glucopyranoside, and (25R)-26-O-(β-d-glucopyranosyl)furost-5-ene-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-xylopyranosyl-(1→3)-β-d-glucopyranoside were quantified in the different organs of L. longiflorum for the first time.     

New oleanane saponins in Chenopodium quinoa

Six triterpenoid saponins were isolated from the seeds of Chenopodium quinoa (Chenopodiaceae). Their structures were as follows: phytolaccagenic acid 3-O-[alpha-L-arabinopyranosyl-(1' '-->3')-beta-D-glucuronopyranosyl]-28-O-beta-D-glucopyranoside (1); spergulagenic acid 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranosyl-28-O-beta-D-glucopyranoside (2); hederagenin 3-O-[beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranosyl]-28-O-beta-D-glucopyranoside (3); phytolaccagenic acid 3-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl]-28-O-beta-D-glucopyranoside (4); hederagenin 3-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl]-28-O-beta-D-glucopyranoside (5); and spergulagenic acid 3-O-[alpha-L-arabinopyranosyl-(1' '-->3')-beta-D-glucuronopyranosyl]-28-O-beta-D-glucopyranoside (6). Saponins 5 and 6 are new. The structures were characterized on the basis of hydrolysis and spectral evidence, including IR, UV, optical rotations, 1D- and 2D-NMR (HMQC and HMBC), ESIMS, and FABMS analyses.     

Structure of steroidal saponins from underground parts of Allium nutans L.

Four steroidal glycosides including deltoside and nolinofuroside D and two novel saponins were isolated from underground parts of Allium nutans L. On the basis of the spectral (LSIMS and NMR) analysis, the structures of the new compounds were established as 25R Delta(5)-spirostan 3beta-ol-3-O-?alpha-L-rhamnopyranosyl(1-->2)-[beta-D-glucopyranosyl(1 -->4)]-O-beta-D-galactopyranoside? and 25R Delta(5)-spirostan 1beta, 3beta-diol 1-O-beta-D-galactopyranoside. On the basis of the extraction efficiency, the concentration of saponins was established to be about 4% of dry matter, which makes this species a good source of steroidal saponins for commercial use.     

Studies on the constituents of Chenopodium quinoa seeds: isolation and characterization of new triterpene saponins

Six triterpenoid saponins were isolated from the edible grain quinoa, which is seeds of Chenopodium quinoa (Chenopodiaceae). Following are their structures: phytolaccagenic acid 3-O-[alpha-L-arabinopyranosyl-(1' '-->3')-beta-D-glucuronopyranosyl]-28-O-beta-D-glucopyranoside (1); phytolaccagenic acid 3-O-[beta-D-glucopyranosyl-(1' '-->3')-alpha-L-arabinopyranosyl]-28-O-beta-D-glucopyranoside (2); phytolaccagenic acid 3-O-[beta-D-glucopyranosyl-(1' "-->3' ')-beta-D-xylopyranosyl-(1' '-->2')-beta-D-glucopyranosyl]-28-O-beta-D-glucopyranoside (3); phytolaccagenic acid 3-O-[beta-D-glucopyranosyl-(1' "-->2' ')-beta-D-glucopyranosyl-(1' '-->3')-alpha-L-arabinopyranosyl]-28-O-beta-D-glucopyranoside (4); oleanolic acid 3-O-[alpha-L-arabinopyranosyl-(1' '-->3')-beta-D-glucuronopyranosyl]-28-O-beta-D-glucopyranoside (5); and oleanolic acid 3-O-[beta-D-glucopyranosyl-(1' '-->3')-alpha-L-arabinopyranosyl]-28-O-beta-D-glucopyranoside (6). The oleanane-type saponins (5, 6) were isolated for the first time in this plant, two of the phytolaccagenane (1, 3) were new compounds and two (2, 4) were previously found in quinoa. The structures were characterized on the basis of hydrolysis and spectral evidence, including 1D- and 2-D NMR (HMQC and HMBC) and ESI-MS analyses.     

New dammarane-type saponins from the galls of Sapindus mukorossi

Five new dammarane-type saponins, 3beta,7beta,20(S),22-tetrahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,23-pentahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,25-pentahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 25-methoxy-3beta,7beta,20(S),22-tetrahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, and 25-methoxy-3beta,7beta,20(R)-trihydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, named sapinmusaponins A (1), B (2), C (3), D (4), and E (5), respectively, together with three known phenylpropanoid glycosides (6-8), were isolated from the galls of Sapindus mukorossi. The structures of these saponins were elucidated on the basis of spectroscopic analyses and chemical methods. Preliminary bioassay data revealed that saponins 1 and 3-5 showed moderate cytotoxic activity (ED50 approximately 9-18 microg/mL) against human tumor cell lines (Hepa59T/VGH, NCI, HeLa, and Med) and that 1-5 were inactive in vitro against HIV replication in H9 lymphocytes.     

Lethal and sublethal effects of withanolides from Salpichroa origanifolia and analogues on Ceratitis capitata

Biological effects on Ceratitis capitata were evaluated for several withanolides isolated from Salpichroa origanifolia (Solanaceae), (20S,22R,24S,25S,26R)-5alpha,6alpha:22,26:24,25-triepoxy-26-hydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide A, 1), (20S,22R,24S,25S,26R)-22,26:24,25-diepoxy-5alpha,6beta,26-trihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide C, 2), (20S,22R,24S,25S,26R)-5alpha,6alpha;22,26:24,25-triepoxy-15,26-dihydroxy-17(13-->18)abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide G, 3), and (20S,22R,24S,25S,26R)-5alpha,6alpha:22,26:24,25-triepoxy-1,26-dihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraene (salpichrolide B, 5), and for chemically modified analogues. Influence of chemical modifications on development delay was analyzed. The compounds were incorporated into the larval diet and the adults' drinking water. Significant development delays from larvae to puparia were observed in treatments with the natural withanolides salpichrolides A, C, and G (1-3) at a concentration of 500 ppm. Salpichrolide B (5) was the most toxic compound, the highest mortality (95%) being observed at the larval stage. Exposure of adults to drinking water containing natural withanolides 1-3 and 5 produced mortality in all cases.     

Response of Tribolium castaneum (Coleoptera, Tenebrionidae) to Salpichroa origanifolia Withanolides.

Biological effects on Tribolium castaneum larvae were evaluated for three withanolides isolated from Salpichroa origanifolia (Solanaceae), (20S,22R,24S,25S,26R)-5alpha,6alpha:22,26:24,25-triepoxy-26-hydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide A, 1), (20S,22R,24S,25S,26R)-22,26:24,25-diepoxy-5alpha,6beta,26-trihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide C, 2), and (20S,22R,24S,25S,26R)-5alpha,6alpha:22,26:24,25-triepoxy-15,26-dihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide G, 3), and for several chemically modified analogues. The compounds were incorporated into the larval diet at concentrations of 500 and 2000 ppm. Salpichrolide C (2) produced a significant delay in the development of neonate larvae to adults at the highest concentration (2000 ppm); development delays and lethal effects were produced by salpichrolides A (1) and G (3) at both concentrations assayed. The size of surviving adults was used as a criterion for assessing feedant deterrent effects; the results suggest that these compounds act as feeding inhibitors. Influence of chemical modifications in development delay was analyzed.     

Antifungal activity and fungal metabolism of steroidal glycosides of Easter lily (Lilium longiflorum Thunb.) by the plant pathogenic fungus, Botrytis cinerea

Botrytis cinerea Pers. Fr. is a plant pathogenic fungus and the causal organism of blossom blight of Easter lily (Lilium longiflorum Thunb.). Easter lily is a rich source of steroidal glycosides, compounds which may play a role in the plant-pathogen interaction of Easter lily. Five steroidal glycosides, including two steroidal glycoalkaloids and three furostanol saponins, were isolated from L. longiflorum and evaluated for fungal growth inhibition activity against B. cinerea, using an in vitro plate assay. All of the compounds showed fungal growth inhibition activity; however, the natural acetylation of C-6' of the terminal glucose in the steroidal glycoalkaloid, (22R,25R)-spirosol-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→2)-[6-O-acetyl-β-D-glucopyranosyl-(1→4)]-β-D-glucopyranoside (2), increased antifungal activity by inhibiting the rate of metabolism of the compound by B. cinerea. Acetylation of the glycoalkaloid may be a plant defense response to the evolution of detoxifying mechanisms by the pathogen. The biotransformation of the steroidal glycoalkaloids by B. cinerea led to the isolation and characterization of several fungal metabolites. The fungal metabolites that were generated in the model system were also identified in Easter lily tissues infected with the fungus by LC-MS. In addition, a steroidal glycoalkaloid, (22R,25R)-spirosol-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (6), was identified as both a fungal metabolite of the steroidal glycoalkaloids and as a natural product in L. longiflorum for the first time.     

Phenylpropanoid glycosides from Tynanthus panurensis: characterization and LC-MS quantitative analysis

A phytochemical analysis of the methanol extract of Tynanthus panurensis bark led to the isolation of one new phenylpropanoid glycoside, eugenol-O-[beta-D-xylopyranosyl-(1-->5)-O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside], the known verbascoside, isoverbascoside, and leucosceptoside, along with the known flavonoid apigenin 8-C-[beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside], namely, katchimoside. Their structures were established by NMR and ESIMS experiments. Additionally, a quantitative study of the phenylpropanoid glycosides fraction of T. panurensis bark and of the hydroalcoholic extract prepared according to the traditional recipe was performed by combining high-performance liquid chromatography diode array detection with positive electrospray ionization tandem mass spectrometry. The new eugenol derivate was found to be the most abundant phenylpropanoid glycoside in both dried bark (19.5 mg/g) and hydroalcoholic extract (0.24 mg/mL). The antioxidant activity of all the isolated compounds and of the methanol and hydroalcoholic extract of the bark was determined by measuring the free radical scavenging effects using the Trolox equivalent antioxidant capacity method. The traditional hydroalcoholic extract showed a moderate activity.     

Triterpene saponins from the roots of Medicago hybrida

Fourteen triterpene saponins (1-14) have been isolated from the roots of Medicago hybrida and their structures elucidated by FAB-MS and NMR analysis. Two of them are new compounds and were identified as hederagenin 3-O-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-28-O-beta-D-glucopyranoside (7) and oleanolic acid 3-O-[beta-D-galactopyranosyl(1-->2)-beta-D-glucuronopyranosyl]-28-O-[alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranoside] (14). Seven saponins being mono- and bidesmosides of hederagenin (1, 5, 6, 9), one bidesmoside of bayogenin (2), and two bidesmosides of 2beta,3beta-dihydroxyolean-12-en-23-al-28-oic acid (11) and oleanolic acid (13) are known compounds but not previously reported as saponin constituents of Medicago, whereas five other saponins, being mono- and bidesmosides of medicagenic acid (3, 4, 8, 10, 12), and one monodesmoside of hederagenin (8) have been previously isolated from other Medicago species. The presence of 2beta,3beta-dihydroxyolean-12-en-23-al-28-oic acid might represent an interesting intermediate in the biosynthesis of these substances.     

Glycosides and phenylpropanoid glycerol in vitis vinifera cv. Gewurztraminer wine

Eight glycosides and a phenylpropanoid glycerol were isolated from Vitis vinifera cv. Gewurztraminer wine, and their structures were elucidated by MS and NMR spectroscopies. cis-1-(5-Ethenyl-5-methyltetrahydrofuran-2-yl)-1-methylethyl O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside, (E)-3,6, 9-trihydroxymegastigm-7-ene 9-O-beta-D-glucopyranoside, 2-phenylethyl O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside, and 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]propane-1,3-diol are reported for the first time as wine components.     

Flavonoids from barrel medic (Medicago truncatula) aerial parts

Twenty-three flavonoids have been identified in the aerial parts of barrel medic, and their structures were established by spectrometric and spectroscopic (ESI-MS/MS and NMR) techniques. Eight of the identified compounds, including apigenin 7-O-beta-D-glucuronopyranosyl-(1-->3)-O-beta-D-glucuronopyranosyl-(1-->2)-O-beta-D-glucuronopyranoside, apigenin 7-O-[2'-O-sinapoyl-beta-D-glucuronopyranosyl-(1-->2)-O-beta-D-glucuronopyranoside], apigenin 7-O-{2-O-feruloyl-[beta-D-glucuronopyranosyl-(1-->3)]-O-beta-D-glucuronopyranosyl-(1-->2)-O-beta-D-glucopyranoside}, chrysoeriol 7-O-[beta-D-glucuronopyranosyl-(1-->2)-O-beta-D-glucuronopyranoside, chrysoeriol 7-O-{2'-O-p-coumaroyl-[beta-D-glucuronopyranosyl-(1-->3)]-O-beta-D-glucuronopyranosyl(1-->2)-O-beta-D-glucuronopyranoside}, tricin 7-O-beta-D-glucuronopyranosyl-4'-O-glucopyranoside, tricin 7-O-[2'-O-feruloyl-beta-D-glucuronopyranosyl-(1-->2)-O-beta-D-glucopyranoside], and tricin 7-O-{2'-O-p-coumaroyl-[beta-D-glucuronopyranosyl-(1-->3)]-O-beta-D-glucuronopyranosyl(1-->2)-O-beta-D-glucuronopyranoside}, have not been reported before in the plant kingdom. Additionally, the presence of two luteolin, three apigenin, one chrysoeriol, and six tricin glycosides, previously identified in alfalfa (Medicago sativa), was confirmed in M. truncatula. Moreover, besides the above flavones, the aerial parts of this species contained three flavonols including rutin, laricitrin 3,7,5'-triglucoside, and laricitrin 3,5'-diglucoside.     

Isolation and identification of novel pyranoanthocyanins from black carrot (Daucus carota L.) juice

Six novel pyranoanthocyanins were identified by HPLC-ESI-MSn in black carrot (Daucus carota L. ssp. sativus var. atrorubens Alef.) juice. The two major compounds, namely, the vinylcatechol adducts of cyanidin 3-O-(6-O-feruloyl-beta-D-glucopyranosyl)-(1-->6)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside and cyanidin 3-O-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside, respectively, were isolated by a combination of high-speed countercurrent chromatography with semipreparative HPLC. Their structures were fully elucidated by means of one- and two-dimensional NMR spectroscopy and high-resolution mass spectrometry. The four remaining pigments were characterized as the vinylphenol and vinylguaiacol adducts of cyanidin 3-O-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside, the vinylguaiacol adduct of cyanidin 3-O-(6-O-feruloyl-beta-D-glucopyranosyl)-(1-->6)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside, and the vinylcatechol adduct of cyanidin 3-O-(6-O-sinapoyl-beta-d-glucopyranosyl)-(1-->6)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside. These compounds are formed during storage of the juice through the direct reaction of either caffeic, ferulic, or coumaric acid with the respective genuine anthocyanins.     

Triterpenoid glycosides from leaves of Medicago arborea L

Eighteen triterpene saponins (1-18) from Medicago arborea leaves have been isolated and their structures elucidated by spectroscopic, spectrometric (1D and 2D NMR, FAB-MS, ESI-MS/MS), and chemical methods. They have been identified as glycosides of medicagenic, zanhic, and 2beta-hydroxyoleanolic acids, soyasapogenol B, bayogenin, and 2beta,3beta-dihydroxyolean-12-en-23-al-28-oic acid. Twelve of them, identified as 3-O-beta-D-glucopyranosyl-28-O-[alpha-L-arabinopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside] zanhic acid (3), 3-O-beta-D-glucopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[alpha-L-arabinopyranosyl-(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside] zanhic acid (4), 3-O-[alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1-->2)-beta-D-glucopyranosyl]-2beta-hydroxyoleanolic acid (5), 3-O-beta-D-glucuronopyranosyl-28-O-[alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]medicagenic acid (6), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]bayogenin (9), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]-2beta,3beta-dihydroxyolean-12-en-23-al-28-oic acid (10), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[beta-D-apiofuranosyl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (12), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[alpha-L-arabinopyranoside(1-->3)]-alpha-L-rhamnopyrano-syl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (13), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyrano-syl(1-->4)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (14), 3-O-[alpha-L-arabinopyranosyl-(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-28-O-[beta-D-xylopyranosyl(1-->4)-[beta-D-apiofurano-syl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (16), 3-O-[beta-D-glucopyrano-syl(1-->2)-beta-D-glucopyranosyl]-28-O-[beta-D-xylopyranosyl(1-->4)-[alpha-L-arabinopyranosyl(1-->3)]-alpha-L-rhamno-pyranosyl (1-->2)-alpha-L-arabinopyranoside]zanhic acid (17), and 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[beta-D-apiofuranosyl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyrano-side]medicagenic acid (18), are reported as new natural compounds. The presence of the aldehydic group on the sapogenin moiety of saponin 10 is discussed in the framework of a possible elucidation of the biosynthesis of these metabolites.