Triterpene and steroid glycosides of theMelilotus genus and their genins I. Melilotosides A,B, and C from the roots ofMelilotus albus

Three new triterpene glycosides of the oleanane series — melilotosides A, B, and C — and the nonglycosylated soyasapogenol B have been isolated from the roots of the plant Melilotus albus Medik. (Leguminosae). The structures of the glycosides have been shown on the basis of chemical transformations and spectral results. Melilotoside A has the structure of soyasapogenol B 3-O-α-L-arabinopyranoside, melilotoside B that of soyasapogenol B 3-O-[O-β-D-galactopyranosyl-(1→2)-α-L-arabinopyranoside], and melilotoside C that of soyasapogenol B 3-O-[O-α-L-rhamnopyranosyl-(1→2)-O-β-D-galactopyranosyl-(1→2)-α-L-arabinopyranoside.     

Triterpene glycosides of Hedera taurica VI. Structures of hederosides G,H1, H2, and I from the berries of Crimean ivy

We have isolated from Crimean ivy berries in addition previously known triterpene glycosides — 3-O-α-L-arabinopyranosyl-28-O-[O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glycopyranosyl-(1 → 6)-β-D-glucopyranosyl]hederagenin, 3-O-[O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl]-28-O-[O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glucopyranosyl-(1 → 6)-β-D-glycopyranosyl]hederagenin, the new triterpene glycosides hederoside H₂-3-O-[O-β-D-glycopyranosyl-(1 → 2)-β-D-glycopyranosyl-(1 → 2)-β-D-glucopyranosyl]-28-O-[O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]oleanolic acid- and hederoside I-3-O-[O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl]-28-O-[O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]hederagenin. Details of their¹³C NMR spectra are given. M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 779–783, November–December, 1990.     

Triterpene and steroid glycosides of theMelilotus genus and their genins I. Melilotosides A, B, and C from the roots ofMelilotus albus

Three new triterpene glycosides of the oleanane series — melilotosides A, B, and C — and the nonglycosylated soyasapogenol B have been isolated from the roots of the plant Melilotus albus Medik. (Leguminosae). The structures of the glycosides have been shown on the basis of chemical transformations and spectral results. Melilotoside A has the structure of soyasapogenol B 3-O--L-arabinopyranoside, melilotoside B that of soyasapogenol B 3-O-[O--D-galactopyranosyl-(12)--L-arabinopyranoside], and melilotoside C that of soyasapogenol B 3-O-[O--L-rhamnopyranosyl-(12)-O--D-galactopyranosyl-(12)--L-arabinopyranoside.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 756–762, November–December, 1994.     

Triterpene and steroid glycosides of the genusMelilotus and their genins II. Melilotoside D from the roots ofMelilotus albus

A new triterpene glycoside of the oleanane series — melilotoside D — has been isolated from the roots of plantMelilotus albus Medik. (Leguminosae). Melilotoside D is a tetraoside of soyasapogenol B. Its structure has been shown on the basis of chemical transformations and spectral characteristics as soyasapogenol B 3-O-{[O-α-L-rhamnopyranosyl-(1→2)]-[O-α-L-arabinopyranosyl-(1→3)]-O-β-D-galactopyranosyl-(1→2)-α-L-arabinopyranoside}.     

New polyhydroxysteroids and steroid glycosides from the far east starfishCeramaster patagonicus

Two new polyhydroxysteroids and five new glycosides were isolated from the starfishCeramaster patagonicus and their structures were elucidated: 5α-cholestane-3β,6α,15β,16β,26-pentol, (22E)-5α-cholest-22-ene-3β,6α,8,15α,24-pentol, (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β,4β, 6α,8,15β,16β,28-heptol (ceramasteroside C₁), (22E)-28-O-[O-(2,4-di-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β, 6α,8,15β,16β,28-hexol (ceramasteroside C₂), (22E)-28-O-[O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β,6α,8,15β,16β 28-hexol (eramasteroside C₃), (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-methyl-5α-cholest-22-ene-3β,4β,6α,8, 15β, 26-hexol (ceramasteroside C₄), and (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-xylopyranosyl]-5α-cholest-22-ene-3β,6α,8,15β,24-pentol (ceramasteroside C₅)). Three known polyhydroxysteroids (24-methylene-5α-cholestane-3β,6α,8,15β,16β,26-hexol, 5α-cholestane-3β,6α,8,15β,16β,26-hexol, and 5α-cholestane-3β,6β,15α,16β,26-pentol) were also isolated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 190–195, January, 1997.     

Triterpene glycosides of Thalictrum squarrosum. IV. Structures of squarrosides A1, A2, B1, and B2

Four new cycloartane glycosides have been isolated from a methanolic extract ofThalictrum squarrosum Stephan ex Willd.: squarroside A1 (I) — (21R, 22S, 23R)-3β-(β-D-glucopyranosyloxy)-21α-methoxy-21,23-epoxycycloart-24-ene-22β,30-diol, C₃₀H₆₀O₁₀; squarroside A2 (II) — the (21S)-epimer of compound (I); squarroside B1 (III) (21R, 22S, 23R)-3gb-[O-α-L-rhamnopyranosyl-(1 → 6)-β-D-glucopyranosyloxy]-21α-methoxy-21,23-epoxycycloart-24-ene-22β,30-diol, C₄₃H₇₀O₁₄; and squarroside B2 (IV) — the (21S)-epimer of compound (III). The proposed structures were determined on the basis of¹H and¹³C NMR spectroscopy, FAB mass spectrometry, and chemical transformations. Irkutsk Institute of Organic Chemistry, Siberian Branch, USSR Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 516–523, July–August, 1989.     

Furostanol Glycosides from leaves of the Chinese plant <Emphasis Type="Italic">Tribulus terrestris</Emphasis>

The structures of five furostanol glycosides (1–5), of which the 26-O-β-D-glucopyranosyl-(25S),5α-furost20(22)-en-12-one-2α,3β,26-triol-3-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (1) was new, from the leaves of Tribulus terrestris L. were established using chemical and NMR spectroscopic methods.     

Triterpene glycosides of Astragalus and their genins XXXV. Cycloaraloside C from Astragalus amarus

A new triterpene glycoside of the cycloartane series (cycloaraloside C) has been isolated from the roots of the plantAstragalus amarus Pall. (Leguminosae). Cycloaraloside C is a bioside of cyclosieversigenin including one D-glucose residue and one D-apiose residue. The structure of the glycoside has been shown on the basis of the chemical transformations and spectral characteristics as 20R,24S-epoxycycloartane-3β,6α,16β,25-tetraol 3-O-[O-(D-apio-β-D-furanosyl)-(1 → 2)-β-D-glucopyranoside]. This is the first time that D-apiose has been found among cycloartane glycosides. Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 783–787, November–December, 1990.     

Triterpene glycosides ofHedera taurica. XI. Structures of taurosides St-G1, St-H1, and St-H2 from the stems of Crimean ivy

The previously known glycosides 3-O-α-L-arabinopyranosyl-28-O-[α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]hederagenin and 3-O-[α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranosyl]-28-O-[α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]hederagenin and the new triterpene glycoside tauroside St-H₁ — 3-O-β-D-glucopyransyl-28-O-[α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]hederagenin — have been isolated from the stems ofHedera taurica Carr. M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 571–579, July–August, 1993.     

Triterpene glycosides fromHedera canariensis VI. Structure of L-G1 and L-G1b glycosides from leaves of canary ivy

Two new minor triterpene glycosides L-G₁, and L-G_2b, the 3-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-gentiobiosyl and 3-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-(6-O-acetyl-β-D-glucopyranosyl)-(1→6)-O-β-D glucopyranosyl esters of 30-norhederagenin, respectively, are isolated from the leaves of canary ivy (Hedera canariensis Willd.). The structures of the glycosides are found by chemical methods and¹H and¹³C NMR spectroscopy. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 623–626, September–October, 1999.     

Triterpene Glycosides from <Emphasis Type="Italic">Cussonia paniculata</Emphasis>. II. Acetylated Glycosides from Leaves

Structures of 13 new acetylated triterpene glycosides from leaves of Cussonia paniculata (Araliaceae) were established as 28-O-(2-O-acetyl- and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β -D-glucopyranosides of 23-hydroxybetulinic acid (1a and 1b) and hederagenin (2a and 2b), 3-O-α-L-arabinopyranosyl-28-O-(2-O-acetyl- and 3-O-acetyl-a-L-rhamnopyranosyl)-(1→ 4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glycopyranosides of oleanic (3a and 3b) and ursolic (3c and 3d) acids, 3-O-α-L-arabinopyranosyl-28-O-(4-O-acetyl-, 2-O-acetyl-, and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosides of hederagenin (4, d5a and 5b), and 3-O-β-D-glucopyranosyl-(1→2)-O-α-L-arabinopyranosyl-28-O-(2-O-acetyl- and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D- glucopyranosides of oleanic acid (6a and 6b). The structures of the compounds were established using chemical methods and NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 351–356, July–August, 2005.     

Triterpene glycosides ofHedera helix I. The structures of glycosides L-1, L-2a,L-2b,L-3, L-4a,L-4b,L-6a,L-6b,L-6c,L-7a,and L7-b from the leaves of common ivy

The leaves of common ivy have yielded 11 triterpene glycosides: the 3-O-α-L-pyranosides of oleanolic acid (1), of echinocystic acid (2), and of hederagenin; the 3-O-[O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside]s of oleanolic acid (4), of echinocystic acid (5), and of hederagenin (6); the O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin 3-O-α-L-pyranoside (7); the O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin 3-O-[O-α-L-pyranosyl-(1→2)-α-L-arabinopyranoside] (9); and the O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl esters of oleanolic acid, echinocystic acid, and hederagenin 3-O-[O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside]s (8), (10), and (11), respectively. This is the first time that compounds (1), (2), (5), (7), (9), and (10) have been found in this plant. Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 742–746, November–December, 1994.     

Acid-mediated cyclotransformations of 4a-substituted 4H-4a,5-dihydroindeno[1,2-<Emphasis Type="Italic">b</Emphasis>]pyridines as a new route to 9a-substituted 1H-fluorenes

4a-Substituted dihydroindenopyridines undergo cleavage of the C_(9b)=N bond in water-containing acidic medium, resulting in the formation of diastereomeric ethyl α-acetyl-β-(2,3-dihydro-1,3-dioxo-1H-inden-2-yl)-β-phenylpropionates and 9a-substituted 1,9a-dihydrofluore-none derivatives. The cyclization of α-acetyl-β-(2,3-dihydro-1,3-dioxo-1H-inden-2-yl)-β-phenyl-propionates with benzylammonium acetate affords 3-benzylamino-1,9a-dihydrofluorenones. The methanobenzo[a]azulene compound is also found among cyclization products. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii. No. 2, pp. 249–258, February, 2007.     

Polar steroidal compounds from the Far-Eastern starfish <Emphasis Type="Italic">Lethasterias fusca</Emphasis>

Nine steroidal compounds including three new steroidal glycosides, viz., sodium (24S)-3,24-di-O-(β-D-xylopyranosyl)-5α-cholestane-3β,6β,8,15α,24-pentol 15-sulfate (fuscaside A), (24S)-3,24-di-O-(β-D-xylopyranosyl)-5α-cholestane-3β,6β,8,15α,24-pentol (fuscaside B), and (22E,24R)-24-O-(β-D-xylopyranosyl)-5α-cholest-22-ene-3β,6α,8,15β,24-pentol (desulfated minutoside A); three previously known glycosides, viz., distolasterosides D₁ and D₂ and pycno-podioside A; two previously known polyhydroxysteroids, viz., 5α-cholestane-3β,6α,8,15β,16β,26-hexaol and 5α-cholestan-3β,4β,6α,7⇇8,15β,16β,26-octol; and the known sodium 24,25-dihydro-marthasterone 3-sulfate were isolated from the Far-Eastern starfish Lethasterias fusca. The structures of these compounds were elucidated by NMR spectroscopy and mass spectrometry. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 196–200, January, 2008.     

Triterpene glycosides of Hedera taurica. III. Structures of hederosides A3, B,E2 and F from the berries of Crimean ivy

Four triterpene glycosides — hederoside A₃, B, E₂, and F — have been isolated from the berries ofHedera taurica Carr. (Crimean ivy), family Araliaceae. On the basis of the results of acid hydrolysis and physiochemical methods of investigation the following structures have been suggested: A₃ — 3-O-(-L-arabinopyranosyl)hederagenin; B — 3-O-(-D-glucopyranosyl)hederagenin; E₂ — 3-O-[O--D-glucopyranosyl-(1 2)--D-glucopyranosyl]oleanolic acid; and F — 3-O-[O--D-glucopyranosyl-(1 2)--D-glucopuranosyl]hederagenin. Hederoside E₂ is a new glycoside of oleanolic aid.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 721–726, September–October, 1988.     

Structural investigation of cellulose Iα and Iβ by 2D RFDR NMR spectroscopy: determination of sequence of magnetically inequivalent d-glucose units along cellulose chain

In our previous studies of the crystal structure of native cellulose (cellulose I) by solid-state two-dimensional (2D) ¹³C–¹³C INADEQUATE, it was revealed that cellulose I_α contains two kinds of β-d-glucose residues (A and A′) in the unit cell and that cellulose I_β contains another two kinds of residues (B and B′). In the present study, the sequence of residues A and A′ along the same chains in cellulose I_α and that of residues B and B′ in I_β were investigated by 2D ¹³C–¹³C rotor-synchronized radiofrequency-driven recoupling (RFDR) experiments using, respectively, uniformly ¹³C₆-labeled (U−¹³C₆) bacterial cellulose and the same [U−¹³C₆] cellulose sample after thermal treatment at 260 °C. The RFDR spectra recorded with a short mixing time (1.0 ms) showed dipolar-coupled ¹³C spin pairs of only the neighboring carbon of the both phases, while those recorded with a longer mixing time (3.0–15 ms) provided correlations between weakly coupled ¹³C spin pairs as well as strongly coupled ¹³C spin pairs such as neighboring carbon nuclei. In the RFDR spectrum of the [U−¹³C₆] cellulose recorded with a mixing time of 15 ms, the inter-residue ¹³C–¹³C correlation between C4 of residue A and C2 of residue A′ and that between C3 of residue A and C4 of residue A′ were clearly observed. In the case of cellulose I_β, however, inter-residue ¹³C–¹³C correlations between residues B and B′ could not be detected in the series of RFDR spectra recorded with different mixing times of annealed [U−¹³C₆] cellulose. From these findings, that cellulose I_α was revealed to have the –A–A′– repeating units along the cellulose chain. For cellulose I_β, it was revealed that the respective residues B and B′ are composed of independent chains (–B–B– and –B′–B′– repeating units) and that there are no –B–B′– repeating units in the chain.     

A new triterpene glycoside from fruit of <Emphasis Type="Italic">Phytolacca americana</Emphasis>

Glycosides H and I, the structures of which were established by modern physicochemical analytical methods (PMR, ¹³C NMR, COSY, TOCSY, HMBC, MS) and acid-base hydrolysis, were isolated from the purified total saponins from fruit of Phytolacca americana containing at least 10 triterpene glycosides by rechromatography of enriched fractions over a column of silica gel. Glycoside H was a bidesmoside of phytolaccageninic acid, which was isolated earlier from cell culture of Phytolacca acinosa. Glycoside I was 3-O-(β-D-xylopyranosyl-(1 → 3)-β-D-galactopyranosyl-(1 → 3)- β -D-xylopyranosyl)-28-O- β -D-glucopyranosyl phytolaccagenin, which was isolated by us for the first time.     

Minor asterosaponin archasteroside C from the starfish <Emphasis Type="Italic">Archaster typicus</Emphasis>

A new minor asterosaponin (20S)-6-O-{β-d-fucopyranosyl-(1→2)-[β-d-fucopyranosyl-(1→4)-β-d-quinovopyranosyl-(1→2)]-β-d-quinovopyranosyl-(1→3)-β-d-quinovopyranosyl}-3β,6α,20-trihydroxycholest-9(11)-en-23-one 3-sulfate (archasteroside C) was isolated from the starfish Archaster typicus collected in shallow coastal waters of Vietnam. The structure of archasteroside C was determined by 2D NMR spectroscopy and electrospray ionization (ESI) tandem mass spectrometry.     

Furostane-Type Steroidal Saponin from <Emphasis Type="Italic">Digitalis ciliata</Emphasis>

A new furostane-type steroidal glycoside and derivative of tigogenin (1) was isolated from aqueous wastes from production of the cardiac drug acetyldigitoxin from leaves of Digitalis ciliata Trautv. (Scrophulariaceae) and characterized. The structure of the glycoside was established using physical constants, chemical transformations, and spectral data as 3-O-β-D-glucopyranosyl-(1→3) [β-D-fucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl-(25R)-5α-furostan-3β,22α,26-triol-26-O-β-D-glucopyranoside.     

Synthesis of aminoethyl glycoside of the oligosaccharide chain of ganglioside Fuc-GM1

2-Aminoethyl glycoside of the hexasaccharide chain of ganglioside Fuc-GM₁ was synthesized by a [3+3] synthetic scheme. At the key step of the synthetic route, glycosylation of the only hydroxyl group at C(4) of the galactose residue in an α-(N-acetylneuraminyl)-(2→3)-β-D-galactopyranosyl-(1→4)-β-D-glucopyranoside derivative with a peracetylated thioglycoside of α-L-fucopyranosyl-(1→2)-β-D-galactopyranosyl-(1→3)-2-trichloroacetamido-2-deoxy-β-D-galactopyranose gave a protected hexasaccharide in high yield. Subsequent removal of the protecting groups gave the target 2-aminoethyl glycoside of the oligosaccharide chain of gan-glioside Fuc-GM₁. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 148–153, January, 2006.