Complete (1)H and (13)C assignments of the four major saponins from Dioscorea villosa (wild yam)

Complete (1)H and (13)C spectral assignments for the four major steroidal saponins isolated by methanolic extraction of the roots of Dioscorea villosa, collected in North Carolina, United States (in summer and autumn), are presented in this paper. The structures were determined by a combination of (1)H, (13)C and 2D NMR techniques and were found to be ((3beta,25R)-26-(beta-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl-O-beta-D-glucopyranosyl-(1 --> 3)-O-beta-D-glucopyranosyl-(1 --> 4)-O-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (1) (or methyl parvifloside), ((3beta,25R)-26-(beta-D-glucopyranosyloxy)-22 methoxyfurost-5-en-3-yl-O-alpha-L-rhamnopyranosyl-(1 --> 2)-O-[beta-D-gluco- pyranosyl-(1 --> 4)]-beta-D-glucopyranoside (2) (or methyl protodeltonin), (3beta,25R)-spirost-5-en-3-yl-O-beta-D-glucopy ranosyl-(1 --> 3)-O-beta-D-glucopyranosyl-(1 --> 4)-O-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (3) (or Zingiberensis saponin I) and (3beta,25R)-spirost-5-en-3-yl-O-alpha-L-rhamnopyranosyl-(1 --> 2)-O-[beta-Ds-glucopyranosyl -(1 --> 4)]-beta-D-glucopyranoside (4) (or deltonin).     

Tyrosinase inhibitory and antileishmanial constituents from the rhizomes of Paris polyphylla

The search for bioactive natural products from the rhizomes of Paris polyphylla (Trilliaceae) has resulted in the isolation of four known constituents, 1,5-dihydroxy-7-methoxy-3-methylanthraquinone (1), diosgenin-3-O-[alpha-L-rhamnopyranosyl-(1 --> 3)-beta-D-glucopyranoside] (2), diosgenin-3-O-[alpha-L-rhamnopyranosyl-(1(Rha) --> 2(Glu))-alpha-L-arabinofuranosyl-(1(Ara) --> 4(Glu))]-beta-D-glucopyranoside (3), and diosgenin-3-O-[alpha-L-rhamnopyranosyl-(1(Rha) --> 2(Glu))-alpha-L-rhamnopyranosyl-(1(Ara) --> 4(Glu))]-beta-D-glucopyranoside (4). Their structures were identified by spectral comparison with the reported data. Compound 1 was isolated for the first time from this genus. The chloroform, ethyl acetate, and butanol extracts of the plant were found to have mild to moderate inhibitory potentials against the enzyme tyrosinase. Compound 1 showed strong (IC(50) = 0.23 microM), while compounds 2-4 and hydrolyzed product 4a showed mild to moderate (IC(50) = 0.93-36.87 microM) activities against the tyrosinase. Similarly, compounds 2-4 and 4a showed mild to moderate (IC(50) = 1.59-83.72 microg mL(-1)) antileishmanial activities.     

New terpenoids from Stachys parviflora Benth

Two new triterpenoidal saponins were isolated from the n-butanolic extract of Stachys parviflora (Lamiaceae). Their structures were elucidated on the basis of spectral data as stachyssaponin A; 3beta, 15alpha, 19alpha, 21beta, 22alpha-pentahydroxyolean-12-ene-28-oic acid 3-O-{alpha-L-rhamnopyranosyl-(1 --> 3)-beta-D-glucopyranoside}-22-O-{alpha-L-arabinofuranosyl-(1 --> 3)-beta-D-glucopyranoside} (1) and stachyssaponin B; 2beta, 3beta, 15alpha, 21beta-tetrahydroxyolean-12-ene-28-oic acid 2-O-[alpha-L-arabinofuranoside]-3, 21-bis-O-[beta-D-glucopyranoside] (2).     

Ardisimamillosides C-F, four new triterpenoid saponins from Ardisia mamillata

Four new triterpenoid saponins, ardisimamilloside C (1), 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->4)-[beta -D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl]-3beta,16al pha,28,30-tetrahydroxy-olean-12-en, ardisimamilloside D (2), 3-O-?alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->4)-[beta -D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl]-3beta,15al pha,28,30-tetrahydroxy-olean-12-en, ardisimamilloside E (3), 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->4)-[beta -D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosl]-13beta,2 8-epoxy-3beta,16alpha,29-oleananetriol, and ardisimamilloside F (4), 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->4)-[beta -D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl]-3beta,16al pha-dihydroxy-13beta,28-epoxy-oleanan-30-oic acid were isolated from the roots of Ardisia mamillata Hance. Structure assignments were established on the basis of highresolution (HR)-FAB-MS, 1H-, 13C-, and two-dimensional (2D)-NMR spectra, and on the chemical evidence.     

Three new steroidal saponins from the rhizome of Paris polyphylla

A mixture of a pair of stereoisomeric new spirostanol saponins (1a and 1b) and a new cholestane saponin (2) were isolated from the rhizome of Paris pollyphylla Smith var. yunnanensis. Their structures were elucidated as (25R)-spirost-5-en-3beta, 7beta-diol-3-O-alpha-L-arabinofuranosyl-(1 --> 4)-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (1a), (25R)-spirost-5-en-3beta, 7alpha-diol-3-O-alpha-L-arabinofuranosyl-(1 --> 4)-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (1b) and 26-O-beta-D-glucopyranosyl-(25R)-Delta(5(6), 17(20))-dien-16, 22-dione-cholestan-3beta, 26-diol-3-O-alpha-L-arabinofuranosyl-(1 --> 4)-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (2) by a combination of HR-ESI-MS, FAB-MS, 1D and 2D NMR techniques (including (1)H-NMR, (13)C-NMR, (1)H--(1)H COSY, HSQC, HMBC and NOESY).     

Cytotoxic triterpenoid saponins from the roots of Cephalaria gigantea

Three new oleanane-type saponins, giganteosides L (1), M (2) and N (3) along with eight known ones were isolated from the roots of Cephalaria gigantea. Their structures were established as 3-O-[beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]-oleanolic acid, 3-O-[beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]-hederagenin, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]-hederagenin, respectively, by means of spectroscopic methods (1D and 2D NMR, HR-ESI-MS). Cytotoxic activity of monodesmosides was investigated in vitro using three cancer cell lines, namely, human non pigmented melanoma MEL-5 and human leukemia HL-60. Giganteosides D (4) and E (5) showed antiproliferative effect on human cell lines with IC(50) values in the range 3.15-7.5 microM.     

Characterization of two minor saponins from Cordia piauhiensis by 1H and 13C NMR spectroscopy

A careful NMR analysis with full assignment of the 1H and 13C spectral data for two minor saponins isolated from stems of Cordia piauhiensis is reported. These saponins were isolated by high-performance liquid chromatography and characterized as 3beta-O-[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl]pomolic acid 28-O-[beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl] ester (1) and 3beta-O-[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl]oleanolic acid 28-O-[beta-D-xylopyranosyl-(1 --> 2)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl] ester (2). Their structures were established using a combination of 1D and 2D (1H, 1H-COSY, TOCSY, NOESY, gs-HMQC and gs-HMBC) NMR techniques, electrospray ionization mass spectrometry and chemical evidence.     

Structure elucidation and complete NMR spectral assignments of two new dammarane-type tetraglycosides from Panax quinquefolium

Two new saponins were isolated from leaves of Panax quinquefolium and their structures were elucidated as 3beta, 12beta, 20S-trihydroxy-25-methoxydammar-23-ene 3-O-{[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[alpha-L-arabinopyranosyl(1-->6)]-beta-D-glucopyranoside (1) and 3beta, 20S-dihydroxy-12beta, 23R-epoxydammar-24-ene 3-O-{[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-xylopyanosyl(1-->6)]-beta-D-glucopyranoside (2) on the basis of (1)D and (2)D NMR (including (1)H, (13)C-NMR, (1)H-(1)H COSY, HSQC, TOCSY, HMBC, and NOESY), ESI-MS spectrometry and chemical methods.     

Two new pregnane glycosides from Dioscorea futschauensis R. KUNTH

Two new pregnane glycosides (1, 2) together with two known saponins were isolated from the rhizomes of Dioscorea futschauensis R. KUNTH. The structures of 1 and 2 were established as 16alpha-methoxyl-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl)oxy]pregn-5-en-20-one and 21-methoxyl-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl)oxy]pregn-5,16-en-20-one, respectively, on the basis of two-dimension NMR (2D NMR) and other spectral analysis. Their in vitro bioactivity against plant pathogenic fungus Pyricularia oryzae and osteoblastic proliferation stimulatory activity in the UMR106 cell line were evaluated.     

Triterpenoid saponin from the bark of Guaiacum officinale L

A new triterpenoid saponin, guaianin R (1) was isolated from the n-BuOH extract of bark of Guaiacum officinale L. It was characterized as akebonic acid-3-O-[alpha-L-rhamnopyranosyl-(1 --> 3)-beta-D-glucopyranosyl-(1 --> 3)-alpha-L-rhamnopyranosyl-(1 --> 2)-alpha-L-arabinopyranoside]-28-O-[beta-D-glucopyranosyl]-ester. The structure was established with the help of a comparative study of 1D and 2D 1H- 13C NMR methods. A number of other saponins were isolated and reported from the same species.     

New phenolic glycosides from the seeds of Cucurbita moschata

Five new phenolic glycosides, cucurbitosides A-E (1-5), were isolated from the seeds of Cucurbita moschata. Their structures were elucidated as 2-(4-hydroxy)phenylethanol 4-O-(5-O-benzoyl)-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (1), 2-(4-hydroxyphenyl)ethanol 4-O-[5-O-(4-hydroxy)benzoyl]-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (2), 4-hydroxybenzyl alcohol 4-O-(5-O-benzoyl)-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (3), 4-hydroxybenzyl alcohol 4-O-[5-O-(4-hydroxy)benzoyl]-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (4) and 4-hydroxyphenyl 5-O-benzoyl-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (5) on the basis of spectroscopic analysis and chemical evidence.     

Triterpene glycosides from the stems of Akebia quinata

The stems of Akebia quinata have been analyzed for their triterpene glycoside constituents, resulting in the isolation of six new triterpene glycosides, along with 19 known ones. On the basis of extensive spectroscopic analysis, including 2D NMR data, and chemical evidence, the structures of the new compounds were deter-mined to be 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-alpha-L-arabinopyranosyl)oxy]olean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]olean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-29-hydroxyolean-12-en-28-oic acid, and 3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-23,29-dihydroxyolean-12-en-28-oic acid, respectively. The main triterpene glycosides contained in the stems of A. quinata were found to have two sugar units at C-3 and C-28 of the aglycone in this study, whereas those of Akebia trifoliate were reported to possess one sugar unit at C-28 of the aglycone. It may be possible to distinguish between A. quinata and A. trifoliate chemically by comparing their triterpene glycoside constituents.     

Ardisimamillosides G and H,two new triterpenoid saponins from Ardisia mamillata

Two new triterpenoid saponins, ardisimamilloside G (1), 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->4)-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl]-13beta,28-epoxy-16-oxo-oleanan-3beta,30-diol and ardisimamilloside H (2), 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->4)-alpha-L-arabinopyranosyl]-3beta-hydroxy-13beta,28-epoxy-16-oxo-oleanan-30-al, were isolated from the roots of Ardisia mamillata HANCE. Structure assignments were established on the basis of spectral data and chemical evidence.     

New phenylethanoid glycosides from Veronica pectinata var. glandulosa and their free radical scavenging activities

A known phenylethanoid glycoside, ehrenoside (1), was isolated together with three new phenylethanoid glycosides, verpectoside A (2), B (3) and C (4) from the aerial parts of Veronica pectinata var. glandulosa. On the basis of spectral analysis (UV, FAB-MS, 1H-, 13C- and 2D-NMR), compounds 2-4 were determined to be 2-(3,4-dihydroxyphenyl)ethyl-O-alpha-L-arabinopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->3)]-(4-O-trans-feruloyl)-beta-D-glucopyranoside, 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-glucopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->3)]-(4-O-trans-caffeoyl)-beta-D-glucopyranoside and 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-glucopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->3)]-(4-O-trans-feruloyl)-beta-D-glucopyranoside, respectively. Isolated phenylethanoid glycosides exhibited potent radical scavenging activity against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical.     

Lupane glycosides from the leaves of Acanthopanax koreanum

Three new lupane-type saponins, acankoreosides F--H (1--3) were isolated from the methanol extract of the leaves of Acanthopanax koreanum NAKAI. The structures of these three saponins were established by chemical and spectroscopic analysis as 3alpha,30-dihydroxylup-20(29)-en-23,28-dioic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (1), 3alpha,30-dihydroxylup-23-al-20(29)-en-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (2), and (20S) 3alpha-hydroxylup-23-al-28,29-dioic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (3), respectively. The effects of the isolates (1-3) on the lipopolysaccharide-induced production of nitric oxide and prostaglandin E2 were evaluated in RAW 264.7 macrophages.     

Monoterpene glycosides from Indigofera hetrantha

Monoterpene glycosides have been isolated from the ethyl acetate soluble fraction of Indigofera hetrantha and their structures assigned to be 3,7-dimethyl-2(E),6-octadien-5-one-1-O-beta-D-6-O-acetylglucopyranoside (1) and 3,7-dimethyl-2(E), 6-octadien-5-one-1-O-[-beta-D-6'-O-acetylglucopyra-nosyl (1' --> 6')-beta-D-glucopyranoside] (2), on the basis of spectroscopic analysis including 1D and 2D NMR techniques. Compounds 1 and 2 displayed moderate inhibitory potential against the enzyme lipoxygenase.     

Studies on the constituents of Luffa acutangula Roxb. I. Structures of acutosides A--G, oleanane-type triterpene saponins isolated from the herb.

From the herb of Luffa acutangula ROXB. (Cucurbitaceae), seven oleanane-type triterpene saponins, acutosides A--G, were isolated and their structures were determined. Acutoside A is oleanolic acid 3-O-beta-D-glucopyranosyl-(1----2)-beta-D-glucopyranoside. Acutosides B, D, E, F and G have a common prosapogenin structure, acutoside A, and only differ in the structures of the ester-linked sugar moieties. Acutoside B is a 28-O-[O-beta-D-xylopyranosyl-(1----4)-O-alpha-L-rhamnopyranosyl-(1----2) -alpha-L-arabinopyranosyl] ester, D is a 28-O-[O-beta-D-xylopyranosyl-(1----3)-O-beta-D-xylopyranosyl-(1----4)-O- alpha-L-rhamnopyranosyl-(1----2)-alpha-L-arabinopyranosyl] ester, E is a 28-O-[O-alpha-L-arabinopyranosyl-(1----3)-O-beta-D-xylopyranosyl-( 1----4)-O-alpha-L-rhamnopyranosyl-(1----2)-alpha-L-arabinopyranosyl] ester, F is a 28-O-[O-beta-D-xylopyranosyl-(1----3)-[O-beta-D-xylopyranosyl-(1----4)-O -alpha-L-rhamnopyranosyl-(1----2)-alpha-L-arabinopyranosyl] ester, and G is a 28-O-beta-D-xylopyranosyl-(1----3)-[O-alpha-L-arabinopyranosyl-(1- ---3)-O-beta-D-xylopyranosyl-(1----4)]-O-alpha-L- rhamnopyranosyl-(1----2)-alpha-L-arabinopyranosyl] ester. Acutoside C is a machaelinic acid (=21 beta-hydroxyoleanolic acid) saponin having the same sugar moiety as that of acutoside B.     

A new oleanane glycoside from the roots of Astragalus caprinus

A novel oleanane-type triterpene saponin (1) together with two known molecules, soyasapogenol B and astragaloside VIII were isolated from the roots of Astragalus caprinus. Their structural elucidation was performed mainly by 2D NMR techniques (COSY, TOCSY, NOESY, HSQC, HMBC) and mass spectrometry. Compound 1 was determined as 3-O-[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucuronopyranosyl]-22-O-beta-D-apiofuranosyl-soyasapogenol B.     

Studies on Balanites aegyptiaca fruits, an antidiabetic Egyptian folk medicine

An aqueous extract of mesocarps of the fruits of Balanites aegyptiaca exhibited a prominent antidiabetic activity by oral administration in streptozotocin induced diabetic mice. From one of the active fractions of this extract, two new steroidal saponins were isolated, and their structures were determined as 26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol 3-O-[alpha-L-rhamnopyranosyl-(1----2)]-[beta-D-xylopyranosyl-(1---- 3)]-[alpha-L-rhamnopyranosyl-(1----4)]-beta-D-glucopyranoside and its 22-methyl ether. In addition, two known saponins, 26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol 3-O-(2,4-di-O-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside and its methyl ether were isolated and identified. It was revealed that the individual saponins did not show antidiabetic activity, while the recombination of these saponins resulted in significant activity. From an ethanolic extract of the epicarps, two known flavonol glycosides, isorhamnetin-3-O-robinobioside and isorhamnetin-3-O-rutinoside were isolated and identified.     

New furostanol saponins from Allium ascalonicum L

An analysis of the polar extracts from Allium ascalonicum L. led to the isolation of two new furostanol saponins (compound 1 and 2) and two known furostanol saponins (compound 3 and 4). On the basis of 1D and 2D NMR (including (1)H, (13)C NMR, (1)H--(1)H COSY, HSQC, TOCSY, HMBC, and NOESY), FAB-MS spectrometry, and chemical methods, their structures were elucidated as (25R)-26-O-beta-D-glucopyranosyl-22-hydroxy-5alpha-furost-2-one-3beta, 5, 6beta, 26-tetraol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (ascalonicoside C, 1), (25R)-26-O-beta-D-glucopyranosyl-22-methoxy-5alpha-furost-2-one-3beta, 5, 6beta, 26-tetraol- 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (ascalonicoside D, 2), (25R)-26-O-beta-D-glucopyranosyl-22-hydroxy-5-ene-furostan-3beta, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (dichotomin, 3), and (25R)-26-O-beta-D-glucopyranosyl-22-hydroxy-5-ene-furostan-3beta, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-arabinofuranosyl-(1-->4)]-beta-D- glucopyranoside (parisaponin I, 4).