Cycloascauloside a from Astragalus caucasicus leaves

The new cycloartane glycoside cycloascauloside A with the structure 20S,24R-epoxycycloartan-3β, 6α,16β,25-tetraol 3-O-[α-L-rhamnopyranosyl(1→6)]-β-D-(2′-O-acetyl)-glucopyranoside was isolated from leaves of Astragalus caucasicus Pall. The structure was established based on IR, PMR, and ¹³C NMR spectra and physicochemical properties of the compound itself and the products of its chemical transformations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 359–361, July–August, 2006.     

Two new isomeric lignans from <Emphasis Type="Italic">Eusideroxylon zwageri</Emphasis>

Two new lignans were isolated with two other known compounds, eusiderin A and eusiderin I, from Eusideroxylon zwageri (billian). The two new lignans have isomeric structure. The structures of the new lignans were determined to be (2R,3R,4S)-2,3-dimethyl-6,7-dimethoxy-4-ethoxy (3′,4′,5′-trimethoxybenzene)-1,5-dihydroxytetralin and (2R,3S,4S)-2,3-dimethyl-6,7-dimethoxy-4-ethoxy(3′,4′,5′-trimethoxybenzene)-1,5-dihydroxytetralin. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 303–305, May–June, 2009.     

New steroidal glycosides from the stem bark of <Emphasis Type="Italic">Mimusops elengi</Emphasis>

Two new steroidal glycosides (1 and 2) have been isolated from the ethanolic extract of the stem bark of Mimusops elengi L. and characterized as stigmasta-5,22-dien-3β-ol-3β-D-glucuropyranosyl-(6′β→1″)-D-glucopyranoside (1) and β-sitosterol-3β-(3″′,6″′,7″′-trihydroxynaphthyl-2″′-carboxyl)-4″-glucopyranosyl-(1″→4′)-glucopyranoside (2) along with the known compounds stigmasta-5-en-3β-ol, lup-20(29)-en-3β-ol, and stigmasta-5-en-3β-D-glucopyranoside. Their structures have been elucidated on the basis of spectral data analysis and chemical reactions.     

Lamiaceae carbohydrates. 1. Pectinic substances and hemicelluloses from <Emphasis Type="Italic">Mentha x piperita</Emphasis>

Pectinic substances from the aerial part of Mentha x piperita were isolated and characterized and found to be a mixture of β-(1→4)-glucogalactan (MPG) and two α-(1→4)-rhamnopolygalacturonans (MPP′-1 and MPP′-2). It was shown that the pectin and its components exhibited membrane-stabilizing, antiatherogenic, and antioxidant activity. Hemicelluloses from M. piperita were a lignocarbohydrate complex. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 411–416, September–October, 2007.     

Structure of a steroid saponin from <Emphasis Type="Italic">Digitalis ciliata</Emphasis>

A new steroid glycoside was isolated from leaves of Digitalis ciliata (Scrophulariaceae) by fractionation of the total extracted substances. Its structure was determined as (25R)-5α-spirostan-3β-ol 3-O-β-D-glucopyranosyl-(1→3)[β-D-fucopyranosyl-(1→2)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside based on chemical transformations, physical constants, and spectral data. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 135–137, March–April, 2007.     

A bicyclo[3.2.1]octanoid neolignan and toxicity of the ethanol extract from the fruit of <Emphasis Type="Italic">Ocotea heterochroma</Emphasis>

A new bicyclo[3.2.1]octanoid neolignan rel-(7S,8R,1′S,2′R,3′S)-Δ8′-2′-hydroxy-5,1′,3′-trimethoxy-3,4methylenedioxy-7,3′,8,1′-neolignan (1) was isolated from ethanol extract from the fruit of Ocotea heterochroma Mez & Sodiro ex Mez as well as the known compounds β-friedelanol (2), meso-dehydroguaiaretic acid (3), and yangambin (4), whose structures were elucidated on the basis of their comprehensive spectroscopic analysis including 2D NMR data. Lethality bioassay using brine shrimp (Artemia salina Leach) was evaluated with the ethanol extract from the Ocotea heterochroma’s fruit. The toxicity of this extract was greater than the toxicity of those fractions obtained in a first solvent partition (benzene, ethyl acetate, and butanol subfractions) and that of a mixture of acetylated 2′-epimers from the new neolignan 1. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 158–160, March–April, 2009.     

Syntheses based on norfluorocurarine. 2. Reduction and dehydrogenation products

The bisindole compound 2β,16α,2′β,16′β(H)-tetrahydronordihydrotoxiferine consisting of two diastereoisomeric deoxytetrahydronorfluorocurarine moieties was isolated from the reduction mixture of the alkaloid norfluorocurarine. 16-Deformyl-2,16,17,20-tetrahydro-20,21-dehydronorfluorocurarine was produced by dehydrogenation of norfluorocurarine; N(β)-methyldihydrodefluorocurarine, by hydrogenation of fluorocurarine. The structures of the synthesized compounds were established by x-ray structure analyses. The configurations of the asymmetric centers in 2β,16α,2′β,16′β(H)-tetrahydronordihydrotoxiferine were determined as 2S,3S,7R,15S,16R,2′S,3′S,7′R,15′S,16′S. Inversion to the R-configuration at the C15 center was observed in N(β)-methyldihydrodefluorocurarine whereas the configurations 3S and 7R were retained. Atom C2 adopted the S-configuration in 16-deformyl-2,16,17,20-tetrahydro-20,21-dehydronorfluorocurarine.     

Steroidal glycosides of gitogenin from Allium rotundum

Two new steroidal glycosides were isolated by fractionation of total extracted substances from inflorescences and flower stalks of Allium rotundum (Alliaceae). The structures were determined on the basis of chemical transformations, physical constants, and spectral data as 26-O-β-D-glucopyranosyl-(25R)-5α-furostan2α,3β,22α,26-tetraol 3-O-β-D-glucopyranosyl-(1 → 2)[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl(1 → 4)-β-D-galactopyranoside (2) and (25R)-5α-spirostan-2α,3β-diol 3-O-β-D-glucopyranosyl-(1 → 3)-βD-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (3).     

Two new triterpenoid saponins from <Emphasis Type="Italic">Lysimachia davurica</Emphasis>

Two new saponins were isolated from an ethanol extract of the whole plants of Lysimachia davuria. The new saponins were respectively characterized as 3-O-{β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranosyl}-3β,28-dihydroxyolean-12-en-30-oic acid-O-[β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl]-ester (1) and 3-O-{ β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranosyl}-3β,28-dihydroxyolean-12-en-30-oic acid-O-β-D-glucopyranosyl-ester (2). Their structures were determined by 1D, 2D NMR and MS techniques. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 466–468, September–October, 2007.     

Separation and identification of steroidal compounds with cytotoxic activity against human gastric cancer cell lines <Emphasis Type="Italic">in vitro</Emphasis> from the rhizomes of <Emphasis Type="Italic">Paris polyphylla</Emphasis> var. <Emphasis Type="Italic">chinensis</Emphasis>

A novel steroidal saponin, along with 12 known steroidal compounds, was isolated from the rhizomes of Paris polyphylla var. chinensis. Spectral data, including two-dimensional NMR, showed that the structure of the novel saponin was 3β,21-dihydroxypregnane-5-en-20S-(22,16)-lactone-1-O-α-L-rhamnopyranosyl(1→2)-[β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside. The isolated steroidal compounds were evaluated for their cytotoxic activity on human gastric cancer cell line HepG₂, SGC7901, BxPC3. Diosgenin-3-O-α-L-rhamnopyranosyl(1→2)[α-L-rabinofuranosyl(1→4)]-β-D-glucopyranoside exhibited the most potent cytotoxic activity among the isolated steroids. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 556–560, November–December, 2007.     

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.     

A novel compound from <Emphasis Type="Italic">Flos carthami</Emphasis> and its bioactivity

A novel compound, 4-{1′-hydroxy-1′-mercapto-1′-[1′′-2′′(N→O)-isoquinolyl]}yl-1-benzoic acid (1), together with six known compounds, 6-hydroxykaempferol-3-O-β-D-glucopyranoside (2), rutin (3), quercetin-3-O-β-D-glucopyranoside (4), kaempferol-3-O-β-D-glucopyranoside (5), cartormin (6), hydroxysafflor yellow A (7), were isolated by chromatography from the n-BuOH fraction of 50% ethanol extraction of Flos carthami. Their structures were elucidated on the basis of spectral analysis and comparison with published data. Among them, compound 1 was shown to possess a weak protective effect against cerebral ischemic damage in rats. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 339–341, May–June, 2009.     

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 from <Emphasis Type="Italic">Astragalus</Emphasis> and their genins. XC. Askendoside K from <Emphasis Type="Italic">Astragalus taschkendicus</Emphasis>

A new triterpene cycloartane glycoside called askendoside K was isolated from roots of Astragalus taschkendicus Bunge (Leguminosae). The structure of this glycoside was established using chemical and biochemical transformations and spectral data. Askendoside K was a bisdesmoside of cycloorbigenin C and had the structure 23R,24R-cycloartan-3β,6α,16β,23,24,25-hexaol 3-O-[(α-L-arabinopyranosyl)(1 → 2)-β-D-xylopyranoside],23-O-[(β-D-glucuronopyranosyl)(1 → 2)-β-D-glucopyranoside].     

Triterpene glycosides from Kalopanax septemlobum. VI. Glycosides from leaves of Kalopanax septemlobum var. typicum introduced to crimea

Thirteen known glycosides of hederagenin and oleanolic acid and the three new triterpene glycosides of oleanolic acid-28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester 3-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→ 3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and the 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosyl esters 3-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and 3-O-β-D-glucopyranosyl-(1→4)-O-β-Dxylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→ 2)-O-α-L-arabinopyranoside of oleanolic acid were isolated from leaves of Kalopanax septemlobum var. typicum introduced to Crimea. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–43, January–February, 2006.     

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.     

New glycosidic and other constituents from hulls of <Emphasis Type="Italic">Oryza sativa</Emphasis>

Three new compounds, 4-hydroxymethylene-7-(9,9,13-trimethylcyclohexyl)-heptanyl-3′,7′,7′-trimethylcyclohexa-2′,4′-dien-1′-oate (1), 1-(n-hexadec-7-enoxy)-6-(n-octadecanoxy)-β-D-glucopyranoside (2), and (Z)-12-hydroxy-9-octadecenoic acid-12-β-D-glucopyranoside (3), along with the known compound hexacosanoic acid (4), were isolated and identified from the rice hulls of Oryza sativa. Their structures were elucidated by 1D and 2D NMR spectroscopic techniques (¹H-¹H COSY, ¹H-¹³C HETCOR, DEPT) aided by EIMS, FABMS, HRFABMS, and IR spectra. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 344–347, July–August, 2007.     

Steroid saponins and sapogenins ofAllium IX. The structure of aginoside

From a methanolic extract of the skins of the bulbs ofAllium giganteum Rgl, a new steroid glycoside has been isolated — aginoside, which is (25R)-5α-spirostan-2α, 3β, 6β-triol 3-0-{[0-β-D-xylopyranosyl-(1→3)-]-[0-β-D-glucopyranosyl-(1→2)]-0-β-D-glucopyranosyl-(1→4)-0-β-D-galactopyranoside}.     

New Oligomeric Proanthocyanidins from Bark of <Emphasis Type="Italic">Platanus orientalis</Emphasis>

Two oligomeric proanthocyanidinglycosides were isolated from bark of Platanus orientalis. Their structures and relative configurations were established as 7-O-β-D-Glcp-(−)-epicatechingallate-(4β-8)-(−)-epicatechin-(4β-8)-(−)-epicatechin-(4β-8)-5-O-β-D-Glcp-epicatechingallate (Pl-1) and 7-O-β-D-Glc→6-O-β-D-Glcp-(−)-epigallocatechingallate-(4β-8)-(+)-catechingallate-(4β-8)-(+)-catechingallate-(4β-8)-(−)-epigallocatechingallate-(4α-8)-(−)-epicatechin-(4β-8)-[5-O-β-D-Glcp-→6-O-β-D-Glc→6-galloyl(−)-epigallocatechingallate (Pl-7). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 325–330, July–August, 2005.     

Synthesis of oligosaccharides related to the HNK-1 antigen. 5. Synthesis of a sulfo-mimetic of the HNK-1 antigenic trisaccharide

2-Aminoethyl 3,6-di-O-sulfo-β-D-glucopyranosyl-(1→3)-β-D-galactopyranosyl-(1→4)-2-acetamido-2-deoxy-β-D-glucopyranoside, which is the sulfo-mimetic of the antigenic trisaccharide HNK-1, and the corresponding monosulfates, viz., 2-aminoethyl 3-O-sulfo-and 2-aminoethyl 6-O-sulfo-β-D-glucopyranosyl-(1→3)-β-D-galactopyranosyl-(1→ 4)-2-acetamido-2-deoxy-β-D-glucopyranosides, were synthesized. 2-Azidoethyl 2,4-di-O-benzoyl-β-D-glucopyranosyl-(1→3)-2,4,6-tri-O-benzoyl-β-D-galactopyranosyl-(1→ 4)-2-acetamido-3,6-di-O-benzyl-2-deoxy-β-D-glucopyranoside served as the common precursor for the sulfated trisaccharides. This compound was synthesized according to the [2+1] pattern from monosaccharidic precursors: 3,6-di-O-acetyl-2,4-di-O-benzoyl-D-glucopyranosyl trichloroacetimidate, allyl 2-O-benzoyl-4,6-O-benzylidene-β-D-galactopyranoside, and 2-azidoethyl 2-acetamido-3,6-di-O-benzyl-2-deoxy-β-D-glucopyranoside. The structures of the glycosyl donors and glycosylation conditions were optimized for the efficient synthesis of the glucosyl-β-(1→3)-galactose disaccharide block and its subsequent transformation into the target trisaccharide sequence. Dedicated to Academician V. A. Tartakovsky on the occasion of his 75th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1593–1607, August, 2007.