New Dammarane‐Type Saponins from the Rhizomes of Panax japonicus

Phytochemical investigation of the rhizomes of Panax japonicus C. A. Meyer (Araliaceae) resulted in the isolation of two new dammarane‐type triterpenoid saponins, yesanchinoside R₁ ( 1 ) and yesanchinoside R₂ ( 2 ), together with one new natural product, 6′′′‐O‐acetylginsenoside Re ( 3 ). In addition, 25 known compounds, including 23 triterpenoid saponins, 4 – 26 , β‐sitosterol 3‐O‐β‐D ‐glucopyranoside ( 27 ), and ecdysterone ( 28 ), were also identified. The known saponins 12, 15 , and 18 – 22 were reported for the first time from the title plant. Their structures were elucidated on the basis of detailed spectroscopic analyses, including 1D‐ and 2D‐NMR techniques, as well as acidic hydrolysis.     

Bidesmosidic Oleanane Saponins from Xerospermum noronhianum

Three new oleanane‐type triterpenoid saponins, 3‐O‐(α‐L ‐rhamnopyranosyl(1→2)‐β‐D ‐fucopyranosyl)‐28‐O‐{[α‐L ‐rhamnopyranosyl(1→2)] [β‐D ‐fucopyranosyl(1→6)]‐β‐D ‐glucopyranosyl} oleanolic acid ( 1 ), 3‐O‐[α‐L ‐rhamnopyranosyl(1→3)‐β‐D ‐fucopyranosyl]‐28‐O‐[α‐L ‐rhamnopyranosyl(1→4)‐β‐D ‐glucopyranosyl] oleanolic acid ( 2 ), and 3‐O‐{α‐L ‐rhamnopyranosyl(1→2)‐[3′,4′‐diacetoxy‐β‐D ‐fucopyranosyl]}‐28‐O‐[α‐L ‐rhamnopyranosyl(1→2)‐β‐D ‐glucopyranosyl] oleanolic acid ( 3 ) have been isolated from the stems of Xerospermum noronhianum. The structures of the saponins were determined as a series of bidesmosidic oleanane saponins based on spectral evidence. The anticholinesterase activity of the saponins 1 – 3 was also evaluated.     

Oleanane Saponins and Glycerogalactolipids from the Leaves of Guapira graciliflora

Two new saponins, 3‐O‐[β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐galactopyranosyl‐(1→3)‐β‐glucuronopyranosyl]oleanolic acid 28‐O‐β‐D ‐glucopyranosyl ester ( 1 ) and the corresponding monodesmoside, 3‐O‐[β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐galactopyranosyl‐(1→3)‐β‐glucuronopyranosyl]oleanolic acid ( 2 ), have been isolated from the leaves of Guapira graciliflora (Nyctaginaceae), together with two further oleanane saponins, 3 and 4 , daucosterol ( 5 ), and two known glycerogalactolipids, 6 and 7 . The structures of the new compounds were established by extensive NMR and MS experiments, in conjunction with acid hydrolysis and sugar analysis. This is the first report on the phytochemistry of plants of the genus Guapira.     

Spirostanol Saponins from the Fibrous Roots of Ophiopogon japonicus (Thunb.) Ker‐Gawl

Three new steroidal saponins, (25R)‐ruscogenin‐3‐yl α‐L ‐rhamnopyranosyl‐(1→2)‐[β‐D ‐xylopyranosyl‐(1→4)]‐β‐D ‐glucopyranoside ( 1 ), diosgenin‐3‐yl 2‐O‐acetyl‐α‐L ‐rhamnopyranosyl‐(1→2)‐[β‐D ‐xylopyranosyl‐(1→4)]‐β‐D ‐glucopyranoside ( 2 ), and pennogenin‐3‐yl 2‐O‐acetyl‐α‐L ‐rhamnopyranosyl‐(1→2)‐[β‐D ‐xylopyranosyl‐(1→4)]‐β‐D ‐glucopyranoside ( 3 ) were isolated from the fibrous roots of Ophiopogon japonicus (Thunb .) Ker‐Gawl . Their structures were determined by spectroscopic methods including IR, HR‐ESI‐MS, and 1D‐ and 2D‐NMR. All of these three steroidal saponins exhibited weak cytotoxicities against Hela and Hep2 cell lines.     

Tetrapterosides A and B,two new oleanane‐type saponins from Tetrapleura tetraptera

From the stem bark of Tetrapleura tetraptera, two new oleanane‐type saponins, tetrapteroside A 3‐O‐{6‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐hydroxyocta‐2,7‐dienoyl]‐β‐D ‐glucopyranosyl‐(1 → 2)‐β‐D ‐glucopyranosyl‐(1 → 3)‐β‐D ‐glucopyranosyl‐(1 → 4)‐[β‐D ‐glucopyranosyl‐(1 → 2)]‐β‐D ‐glucopyranosyl}‐3,27‐dihydroxyoleanolic acid (1), and tetrapteroside B 3‐O‐{ β‐D ‐glucopyranosyl‐(1 → 2)‐6‐O‐[(E)‐feruloyl]‐β‐D ‐glucopyranosyl‐(1 → 3)‐β‐D ‐glucopyranosyl‐(1 → 4)‐[β‐D ‐glucopyranosyl‐(1 → 2)]‐β‐D ‐glucopyranosyl}‐3,27‐dihydroxyoleanolic acid (2), were isolated. Further extractions from the roots led to the isolation of four known oleanane‐type saponins. Their structures were elucidated by the combination of mass spectrometry (MS), one and two‐dimensional NMR experiments. Copyright © 2009 John Wiley & Sons, Ltd.     

Structure elucidation of new oleanane‐type glycosides from three species of Acanthophyllum

From the roots of three species of Acanthophyllum (Caryophyllaceae), two new gypsogenic acid glycosides, 1 and 2, were isolated, 1 from A. sordidum and A. lilacinum, 2 from A. elatius and A. lilacinum, together with three known saponins, glandulosides B and C, and SAPO50. The structures of 1 and 2 were established mainly by 2D NMR techniques as 23‐O‐β‐D ‐galactopyranosylgypsogenic acid‐28‐O‐β‐D ‐glucopyranosyl‐(1→3)‐[β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐galactopyranoside (1) and gypsogenic acid‐28‐O‐β‐D ‐glucopyranosyl‐(1→3)‐[β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐galactopyranoside (2). The cytotoxicity of several of these saponins was evaluated against two human colon cancer cell lines (HT‐29 and HCT 116). Copyright © 2010 John Wiley & Sons, Ltd.     

New Steroidal Saponins from the Leaves of Yucca elephantipes

Two new spirostanol saponins, namely elephanosides G and H ( 1 and 2 , resp.) were isolated from the leaves of Yucca elephantipes (Agavaceae), together with the two known furostanol saponins 3 and 4 and the six known flavonoid O‐ and C‐glycosides 5 – 10 . The new structures were elucidated as (3β,25S)‐spirost‐5‐en‐3‐yl O‐β‐D ‐glucopyranosyl‐(1→3)‐O‐β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 1 ) and (3β,5β,25R)‐3‐[(2‐O‐β‐D ‐glucopyranosyl‐β‐D ‐galactopyranosyl)oxy]spirostan‐12‐one ( 2 ) on the basis of detailed spectroscopic analysis and acidic hydrolysis.     

New Triterpenoid Saponins from the Roots of Gypsophila paniculata L.

The seven new triterpenoid saponins 1 – 7 were isolated from the roots of Gypsophila paniculata L. Their structures were established by 1D ‐ and 2D‐NMR techniques, HR‐MS, and acid hydrolysis. The isolated compounds include 3,28‐O‐bidesmosides with or without a 4‐methoxycinnamoyl group (see 1 vs. 2 and 3 ), and 3‐O‐monoglucosides 4 – 7 . All isolated saponins 1 – 7 and their aglycones were evaluated for their α‐glucosidase inhibition activity. Compound 1 showed inhibitory activity against yeast α‐glucosidase with an IC₅₀ value of 100.9±3.3 μM , whereas compounds 2 – 7 were inactive.     

Oleanane Saponins from Rhizome of Anemone raddeana

Two new oleanolic acid‐type triterpenoid saponins, raddeanosides R₂₂ and R₂₃ ( 1 and 2 , resp.), together with four known saponins were isolated from the rhizome of Anemone raddeana Regel. The structures of the new compounds were elucidated as oleanolic acid 3‐O‐β‐D ‐glucopyranosyl(1→2)[β‐D ‐glucopyranosyl(1→4)]‐α‐L ‐arabinopyranoside ( 1 ) and oleanolic acid 3‐O‐α‐L ‐arabinopyranosyl(1→3)‐α‐L ‐rhamnopyranosyl(1→2)[β‐D ‐glucopyranosyl(1→4)]‐α‐L ‐arabinopyranoside ( 2 ). The four known compounds were identified as oleanolic acid 3‐O‐α‐L ‐arabinopyranoside ( 3 ), oleanolic acid 3‐O‐β‐D ‐glucopyranosyl(1→4)‐α‐L ‐arabinopyranoside ( 4 ), hederasaponin B ( 5 ), and hederacholchiside E ( 6 ) on the basis of chemical and spectral evidences. Compound 4 is reported for the first time from the Anemone genus, while the other three known compounds have been already found in this plant.     

Pentacyclic Triterpenoid Saponins from Silene viscidula

Three new pentacyclic triterpenoid saponins, viscidulosides A and B ( 1 and 2 , resp.), and silenoviscoside D ( 3 ), were isolated from the roots of Silene viscidula, together with two known saponins, sinocrassulosides VIII and IX ( 4 and 5 , resp.). Their structures were elucidated by spectroscopic data and chemical methods. Compounds 1 / 2 and 4 / 5 were two inseparable mixtures, which are glycosides of quillaic acid whose fucose residue is acylated by (E)‐ or (Z)‐4‐methoxycinnamic acid.     

Two New Steroidal Saponins from the Processed Polygonatum kingianum

Two new spirostanol saponins, kingianoside I ( 1 ) and kingianoside K ( 2 ), corresponding to (3β,23S,25R)‐23‐hydroxy‐12‐oxospirost‐5‐en‐3‐yl 4‐O‐β‐D ‐glucopyranosyl‐β‐D ‐galactopyranoside ( 1 ) and (3β,25R)‐7‐oxospirost‐5‐en‐3‐yl α‐L ‐arabinofuranosyl‐(1→4)‐[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 2 ), along with 13 known compounds, daucosterol, (25R)‐kingianoside G, (25RS)‐kingianoside A, pratioside D₁, (25RS)‐pratioside D₁, (25S)‐kingianoside C, kingianoside C, ginsenoside Rb₁, saponins Tb and Pb, dioscin, gracillin, and saponin Pa, were isolated from the processed rhizomes of Polygonatum kingianum. The structures of the new compounds were elucidated by detailed spectroscopic analyses, including 1D‐ and 2D‐NMR techniques, and chemical methods. Compound 2 contains a novel unusual spirostanol saponin aglycone. Ginsenoside Rb₁ and saponin Tb were isolated for the first time from the genus Polygonatum. The 13 known compounds were detected for the first time in the processed Polygonatum kingianum.     

New Triterpenoid Saponins from Achyrantes aspera Linn.

Two new bisdesmosidic triterpenoid saponins, i.e. 1 and 2 , were isolated, besides the three known saponins 3 – 5 , from the MeOH extract of the aerial parts of Achyranthes aspera Linn. (Amaranthaceae). Their structures were elucidated as β‐D ‐glucopyranosyl 3β‐[O‐α‐L ‐rhamnopyranosyl‐(1→3)‐O‐β‐D ‐glucopyranuronosyloxy]machaerinate ( 1 ) and β‐D ‐glucopyranosyl 3β‐[O‐β‐D ‐galactopyranosyl‐(1→2)‐O‐α‐D ‐glucopyranuronosyloxy]machaerinate ( 2 ) by NMR spectroscopy, including 2D‐NMR experiments (machaerinic acid=3β,21β‐dihydroxyolean‐12‐en‐28‐oic acid). The other saponins were identified as β‐D ‐glucopyranosyl 3β[O‐α‐L ‐rhamnopyranosyl‐(1→3)‐O‐β‐D ‐glucopyranuronosyloxy]oleanolate ( 3 ), β‐D ‐glucopyranosyl 3‐β‐[O‐β‐D ‐galactopyranosyl‐(1→2)‐O‐β‐D ‐glucopyranuronosyloxy]oleanolate ( 4 ), and β‐D ‐glucopyranosyl 3β‐[O‐β‐D ‐glucopyranuronosyloxy]oleanolate ( 5 ) (oleanolic acid=3β‐hydroxyolean‐12‐en‐28‐oic acid).     

New saponins from Sechium mexicanum

The chemical study of Sechium mexicanum roots led to the isolation of the two new saponins {3‐O‐β‐D ‐glucopyranosyl (1 → 3)‐β‐D ‐glucopyranosyl‐2β,3β,16α,23‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐O‐α‐L ‐rhamnopyranosyl‐(1 → 3)‐β‐D ‐xylopyranosyl‐(1 → 4)‐α‐L ‐rhamnopyranosyl‐(1 → 2)‐α‐L ‐arabinopyranoside} (1) and {3‐O‐β‐D ‐glucopyranosyl (1 → 3)‐β‐D ‐glucopyranosyl‐2β,3β,16α,23‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐O‐α‐L ‐rhamnopyranosyl‐(1 → 3)‐β‐D ‐xylopyranosyl‐(1 → 4)‐[β‐D ‐apiosyl‐(1 → 3)]‐α‐L ‐rhamnopyranosyl‐(1 → 2)‐α‐L ‐arabinopyranoside} (2), together with the known compounds {3‐O‐β‐D ‐glucopyranosyl‐(1 → 3)‐β‐D ‐glucopyranosyl‐2β,3β,6β,16α,23‐pentahydroxyolean‐12‐en‐28‐oic acid 28‐O‐α‐L ‐rhamnopyranosyl‐(1 → 3)‐β‐D ‐xylopyranosyl‐(1 → 4)‐α‐L ‐rhamnopyranosyl‐(1 → 2)‐α‐L ‐arabinopyranoside} (3), tacacosides A₁ (4) and B₃ (5). The structures of saponins 1 and 2 were elucidated using a combination of ¹H and ¹³C 1D‐NMR, COSY, TOCSY, gHMBC and gHSQC 2D‐NMR, and FABMS of the natural compounds and their peracetylated derivates, as well as by chemical degradation. Compounds 1–3 are the first examples of saponins containing polygalacic and 16‐hydroxyprotobasic acids found in the genus Sechium, while 4 and 5, which had been characterized partially by NMR, are now characterized in detail. Copyright © 2009 John Wiley & Sons, Ltd.     

Tensioactive Compounds from the Aquatic Plant Ranunculus fluitans L. (Ranunculaceae)

In the search for the cause for the formation of persistent foam in the Rhine River below the Rhine Fall at Schaffhausen, an investigation of the tensioactive principles from the aquatic plant Ranunculus fluitans L. (Ranunculaceae) was carried out. Two new (see 1 and 2 ) and four known bisdesmosidic triterpene saponins (see 4 – 6 ) were isolated along with the two known diacylglycerol galactosides 7 and 8 . The saponin structures were established by the identification of the aglycon and sugar moieties by HPLC and chiral capillary zone electrophoresis (CZE), ion‐spray LC/MS and extensive 1‐ and 2D homo‐ and heteronuclear NMR spectroscopy. The structures of the new oleanane‐type saponins were identified as 3‐O‐[β‐D ‐glucopyranosyl‐(1→3)‐α‐L ‐arabinopyranosyl]‐28‐O‐[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl]hederagenin ( 1 ) and 3‐O‐[β‐D ‐glucopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl]oleanolic acid [α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl] ester ( 2 ). LC/MS Studies of tensioactive fractions revealed the presence of additional glycoglycerolipids.     

Triterpene Saponins from Entada phaseoloides

Four oleanane‐type triterpene saponins, phaseoloideside A–D ( 1 – 4 ), were isolated from the seed kernels of Entada phaseoloides, along with rheediinoside B. The structures of the four new compounds were established by 2D‐NMR spectroscopic methods, HR‐ESI‐MS analysis, and chemical degradation. Phaseoloideside D ( 4 ) showed cytotoxic activity against the Eca‐109 cell line with an IC₅₀ value of 28.0 μM .     

New Triterpenoid Glycosides from the Roots of Camellia oleifera Abel

Five new triterpenoid saponins, oleiferosides I–M ( 1 – 5 , resp.) were isolated from the roots of Camellia oleifera Abel . Their structures were elucidated by a combination of 1D‐ and 2D‐NMR spectroscopy, mass spectrometry, and chemical methods. All the compounds were identified as oleanane‐type saponins with sugar moieties linked to C(3) of the aglycone. In addition, cytotoxic activities of these saponins were evaluated against four human tumor cell lines (A549, B16, BEL‐7402, and MCF‐7) by using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) in vitro assay. All of the compounds showed significant cytotoxic activities against the tested cell lines.     

Two new complex triterpenoid saponins from Gledistsia dolavayi Franch.

Two new triterpenoid saponins, gledistside A ( 1 ) and gledistside B ( 2 ), isolated from the fruits of Gledistsia dolavayi Franch., were characterized as the 3,28‐O‐bisdesmoside of echinocystic acid acylated with monoterpene carboxylic acids. On the basis of spectroscopic and chemical evidence, their structures were elucidated as 3‐O‐β‐D ‐xylopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl‐28‐O‐β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐xylopyranosyl‐(1→4)‐[β‐D ‐galactopyranosyl‐(1→2)]‐α‐L ‐rhamnopyranosyl‐(1→2)‐{6‐O‐[2,6‐dimethyl‐6(S)‐hydroxy‐2‐trans‐2,7‐octadienoyl]}‐β‐D ‐glucopyranosylechinocystic acid ( 1 ) and 3‐O‐β‐D ‐xylopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl‐28‐O‐β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐xylopyranosyl‐(1→4)‐[β‐D ‐galactopyranosyl‐(1→2)]‐α‐L ‐rhamnopyranosyl‐(1→2)‐{6‐O‐[2‐hydroxymethyl‐6‐methyl‐6(S)‐hydroxy‐2‐trans‐2,7‐octadienoyl]}‐β‐D ‐glucopyranosylechinocystic acid ( 2 ). The complete ¹H and ¹³C assignments of saponins 1 and 2 were achieved on the basis of 2D NMR spectra including HMQC‐TOCSY, TOCSY, ¹H–¹H COSY, HMBC, ROESY and HMQC spectra. Copyright © 2002 John Wiley & Sons, Ltd.     

Three New Triterpene Saponins from Bolbostemma paniculatum

Two novel noroleanane saponins, tubeimoside A ( 1 ) and tubeimoside B ( 2 ), and a new dammarane triterpene saponin, tubeimoside C ( 3 ), together with two known compounds, 4 and 5 , were isolated from the bulbs of Bolbostemma paniculatum (Maxim .) Franquet . Compound 4 was found in this genus for the first time. Based on spectroscopic methods, including IR, NMR (DEPT, COSY, HMQC, HMBC, and TOCSY), and MS experiments, and chemical reactions, the structures of the new compounds were elucidated as 3β‐[β‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyloxy]‐2β,23‐dihydroxy‐28‐norolean‐12‐en‐16‐one ( 1 ), 3β‐[β‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyloxy]‐2β,23‐dihydroxy‐28‐norolean‐12‐en‐22‐one ( 2 ), (3β,7β)‐7,18,20‐trihydroxydammar‐24‐en‐3‐yl 2‐O‐α‐L ‐arabinopyranosyl‐β‐D ‐glucopyranoside ( 3 ).     

Two New Cytotoxic Spirostane‐Steroidal Saponins from the Roots of Bletilla striata

Two new spirostane‐steroidal saponins, bletilnoside A ( 1 ) and bletilnoside B ( 2 ), together with five known compounds, 3 – 7 , were isolated from the roots of Bletilla striata (Thunb .) Reichb . F. The structures of the new compounds were determined based on their 1D‐ and 2D‐NMR spectral data. The isolated compounds 1 – 7 were tested for cytotoxicity against four human tumor cells (A549, SK‐OV‐3, SK‐MEL‐2, and HCT15) in vitro using a sulforhodamin B bioassay, and compounds 1, 2 , and 5 showed significant cytotoxicities against all tested tumor cell lines with IC₅₀ values ranging from 3.98±0.16 to 12.10±0.40 μM .     

Triterpenoid Saponins from Schefflera arboricola

Four new triterpenoid saponins, named scheffarboside A – D ( 1 – 4 ), along with five known saponins were isolated from the stems of Schefflera arboricola. The structures of the four new saponins were determined as 3‐O‐(O‐β‐glucuronopyranosyl‐(1 → 3)‐O‐α‐rhamnopyranosyl‐(1 → 2)‐α‐arabinopyranosyl)oleanolic acid ( 1 ), 3‐O‐(O‐α‐arabinopyranosyl‐(1 → 4)‐O‐α‐arabinopyranosyl‐(1 → 3)‐O‐α‐rhamnopyranosyl‐(1 → 2)‐α‐arabinopyranosyl)oleanolic acid ( 2 ), 3‐O‐(O‐α‐arabinopyranosyl‐(1 → 4)‐O‐α‐arabinopyranosyl‐(1 → 3)‐O‐α‐rhamnopyranosyl‐(1 → 2)‐α‐arabinopyranosyl)hederagenin ( 3 ), 3‐O‐(O‐α‐arabinopyranosyl‐(1 → 4)‐O‐α‐arabinopyranosyl‐(1 → 3)‐O‐α‐rhamnopyranosyl‐(1 → 2)‐α‐arabinopyranosyl)oleanolic acid O‐α‐rhamnopyranosyl‐(1 → 4)‐O‐β‐glucopyranosyl‐(1 → 6)‐β‐glucopyranosylester ( 4 ), respectively, on the basis of spectroscopic and chemical degradation methods.