A new flavone glucoside from Stachys aegyptiaca

In addition to 5,7,3′-trihydroxy-6,4′-dimethoxyflavone, 5,7,3′-trihydroxy-6,8,4′-trimethoxyflavone, isoscutellarein, luteolin, and luteolin-7-O-glucoside, the methanol extract of the aerial parts of Stachys aegyptiaca yielded a new flavone identified as luteolin 3′,4′-dimethylether-7-O-β-D-glucoside on the basis of chemical and spectroscopic methods. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 444–445, September–October, 2007.     

The synthesis ofN-acetyl-β-l-fucosamine-1-phosphate and uridine 5′-diphospho-N-acetyl-β-l-fucosamine

Uridine 5′-(2-acetamido-2,6-dideoxy-β-l-galactopyranosyl) diphosphate (uridine 5′-diphospho-N-acetyl-β-l-fucosamine) was synthesized. The key intermediate, 3,4-di-O-acetyl-2-azido-2,6-dideoxy-β-l-galactopyranosyl dibenzyl phosphate, was prepared by a previously unknown reaction of cesium dibenzyl phosphate with the corresponding α-glycosyl nitrate and was then converted into theN-acetylated glycosyl phosphate and nucleoside diphosphate sugarsvia 3,4-di-O-acetyl-2-amino-2,6-dideoxy-β-l-galactopyranosyl phosphate using mildN-acetylation andO-deacetylation as the last synthetic steps. Published inIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 1919–1923, November, 2000.     

Ellagic acid glycosides from the stem bark of <Emphasis Type="Italic">Aphananthe aspera</Emphasis>

Five ellagic acid glycosides were isolated from Aphananthe aspera and their structures were identified as 3-O-methylellagic acid-4′-O-α-L-rhamnopyranoside (1), 3-O-methylellagic acid-4′-O-β-D-xylopyranoside (2), 3,3′-di-O-methylellagic acid-4′-O-β-D-xylopyranoside (3), 3,3′, 4-tri-O-methylellagic acid-4′-O-β-D-glucopyranoside (4), and 3,3′-di-O-methylellagic acid-4′-O-α-L-rhamnopyranoside (5) on the basis of spectroscopic analysis. Compound 1 is new, and all the compounds were isolated for the first time from the title plant. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 458–459, September–October, 2007.     

Cardiac glycosides from Strophanthus kombe

Twelve cardiac glycosides and aglycons were isolated from Strophanthus kombe seeds. Of these, eight were identified as cymarin, K-strophanthin-β, K-strophanthoside, periplocymarin, 17α-strophadogenin, erysimin (= helveticoside), erysimoside, and neoglucoerysimoside. Four glycosides, preliminarily designated Sk-x, Sk-y, Sk-z, and Sk-20, were new. Their chemical structures were established as 3β-O-β-D-glucopyranosyl-5β,14β,16β-trihydroxy-19-oxo-17α-card-20(22)enolide (17α-strophadogenin-3-O-β-D-glucoside), 3β-O-β-D-cymaropyranosyl-5β,14β,16β-trihydroxy-19-oxo-17α-card-20(22)enolide (17α-strophadogenin-3-O-β-D-cymaroside), 3β-O-β-D-cymaropyranosyl-4′-O-β-D-glucopyranosyl-6″-O-β-D-glucopyranosyl-5β, 14β,16β-trihydroxy-19-oxo-17α-card-20(22)enolide (17α-strophadogenin-3-O-strophanthotrioside), and 3-O-β-D-digitoxopyranosyl-4′-O-β-D-glucopyranosyl-6″-O-β-D-glucopyranosyl-5β,14β, 19-trihydroxy-card-20(22)enolide (strophanthidol-3-O-gentiobiosyldigitoxoside), respectively. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 156–159, March–April, 2006.     

Isoflavone glycosides from the bark of Amorpha fruticosa

Four known isoflavone glucosides have been isolated from the bark of Amorpha fruticosa, which is a traditional remedy plant, for the first time. They were elucidated as 3′-hydroxy-4′-methoxyisoflavone-7-O-β-D-glucopyranoside (1), 4′,6-dimethoxyisoflavone-7-O-β-D-glucopyranoside (2), 4′-methoxyisoflavone-7-O-β-D-glucopyranoside (3), and 3′,5-dihydroxy-4′-methoxyisoflavone-7-O-β-D-glucopyranoside (4), based on the UV, FT-IR, EIMS, FABMS, HREIMS, and NMR (¹H and ¹³C, DEPT, COSY, NOESY, HMQC, and HMBC) data. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 336–338, July–August, 2006.     

A new stilbene glycoside from the <Emphasis Type="Italic">n</Emphasis>-butanol fraction of <Emphasis Type="Italic">Veratrum dahuricum</Emphasis>

A new stilbene glycoside, 5-methylresveratrol-3,4′-O-β-D-diglucopyranoside (1), was isolated from the n-butanol fraction of the rhizomes of Veratrum dahuricum, together with five known stilbenoids: resveratrol-3-O-β-D-glycoside (2), 4′-methylresveratrol-3-O-β-D-glycoside (3), oxyresveratrol-4′-O-β-D-glycoside (4), oxyresveratrol-3-O-β-D-glycoside (5), and oxyresveratrol-3,4′-O-β-D-diglycoside (6), and found for the first time in the investigated plant. The structures of six isolates were identified on the basis of 1D and 2D NMR data. Compounds 1–6 showed platelet aggregation inhibition, and compound 1 had an IC₅₀ value of 383.6 μM against platelet aggregation induced by AA. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 279–282, May–June, 2009.     

Ellagic acid derivatives from the stem bark of <Emphasis Type="Italic">Dipentodon sinicus</Emphasis>

Ellagic acid derivatives were isolated from Dipentodon sinicus and their structures were identified as 3,3′,4′-tri-O-methylellagic acid (1), 3,3′-di-O-methylellagic acid (2), 4,4′-di-O-methylellagic acid (3), 3,3′-di-O-methylellagic acid-4′-O-α-L-rhamnopyranoside (4), 3,3′,4′-tri-O-methylellagic acid-4′-O-β-D-glucopyranoside (5), 3,3′-di-O-methylellagic acid-4′-O-β-D-glucopyranoside (6), and ellagic acid (7). All the compounds were isolated for the first time from the title plant. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 106–107, March–April, 2007.     

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.     

Flavonoids from the aerial part of <Emphasis Type="Italic">Vicia subvillosa</Emphasis>

The new flavone glucoside viscioside, luteolin-4′-O-β-D-galactopyranoside, in addition to the known flavonoids apigenin, luteolin, quercetin, cinaroside, luteolin-4′-O-β-D-glucoside, and isoquercitrin were isolated from the aerial part of Vicia subvillosa. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 30–31, January–February, 2007.     

Synthesis of succinic acid 12α-deoxoartemisinyl ester 4′-O-demethyl-4β-(4″-nitroanilino)-4-desoxypodophyllotoxin

The succinic acid 12α-deoxoartemisinyl ester 4′-O-demethyl-4-β-(4″-nitroanilino)-4-desoxypodophyllotoxin was synthesized for the first time. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 442–443, September–October, 2007.     

Two new benzoyl esters of glucose from Lagotis yunnanensis

Two new benzoyl esters of glucose 1-O-(E)-4′-methoxybenzoyl-β-D-glucopyranose (1) and 1-O-(E)-4′-methoxybenzoyl-β-D-gluconic acid (2) were isolated from Lagotis yunnanensis, together with six previously known iridoid glucosides. The structures of these compounds were elucidated on the basis of spectral analysis, including 2D NMR spectroscopy. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 529–530, November–December, 2006.     

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.     

New oligomeric proanthocyanidin glycosides platanoside-A and platanoside-B from <Emphasis Type="Italic">Platanus orientalis</Emphasis> trunk bark

Two new oligomeric proanthocyanidin glycosides were isolated from trunk bark of Platanus orientalis. Their structures and relative configurations were found to be 7-O-β-D-Glcp-(–)-epicatechin-(4β-8)-(–)-epicatechin(4β-8)-(–)-epicatechin-3-O-gallate (platanoside-A) and 7-O-β-D-Glc \textp\xrightarrow6 {\text{p}}\xrightarrow{6} galloyl-(+)-catechin-3-O-gallate(4α-8)-(–)-epicatechin-3-O-gallate-(4β-8)-(–)-epicatechin-3-O-gallate-(4β-8)-5-O-β-D-Glcp-(–)epicatechin-3-O-gallate (platanoside-B).     

Balanoinvolin,a new steroid derivative from <Emphasis Type="Italic">Balanophora involucrate</Emphasis>

A new compound, β-sitosterylglucoside-3′-O-linoleate, named balanoinvolin, and three known compounds coniferin, methylconiferin, and 4-O-β-D-glucopyranosylconiferyl aldehyde, were isolated from Balanophora involucrate Hook. f. and their structures were determined by MS and 1D/2D NMR spectra. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 315–317, May–June, 2009.     

Young’s modulus calculations for cellulose I<Subscript>β</Subscript> by MM3 and quantum mechanics

Quantum mechanics (QM) and molecular mechanics (MM) calculations were performed to elucidate Young’s moduli for a series of cellulose I_β models. Computations using the second generation empirical force field MM3 with a disaccharide cellulose model, 1,4′-O-dimethyl-β-cellobioside (DMCB), and an analogue, 2,3,6,2′,3′,6′-hexadeoxy-1,4′-O-dimethyl-β-cellobioside (DODMCB), that cannot make hydrogen bonds reveal a considerable contribution of intramolecular hydrogen bonding to the molecular stiffness of cellulose I_β; the moduli for DMCB and DODMCB being 85.2 and 37.6 GPa, respectively. QM calculations confirm this contribution with modulus values of 99.7 GPa for DMCB and 33.0 GPa for DODMCB. However, modulus values for DMCB were considerably lower than values previously reported for cellulose I_β. MM calculations with extended cellulose chains (10–40 glucose units) resulted in modulus values, 126.0–147.5 GPa, more akin to the values reported for cellulose I_β. Comparison of the cellodecaose model, 1,4′-O-dimethyl-β-cellodecaoside (DMCD), modulus with that of its hydrogen bonding-deficient analogue, 2,3,6,2′,3′,6′-hexadeoxy-1,4′-O-dimethyl-β-cellodecaoside (DODMCD), corroborates the observed stiffness conferred by intramolecular hydrogen bonds; the moduli for DMCD and DODMCD being 126.0 and 63.3 GPa, respectively. Additional MM3 determinations revealed that modulus values were not strongly affected by intermolecular hydrogen bonding, with multiple strand models providing values similar to the single strand models; 87.5 GPa for a 7-strand DMCB model and 129.5 GPa for a 7 strand DMCD model.     

Synthesis of f luorescein-labeled oligonucleotides bearing a tag in position 2′ of modified adenosine and arabinoadenosine

Oligonucleotide conjugates containing fluorescein residues in the sugar-phosphate back-bone were synthesized by the standard solid-phase phosphoramidite method using phosphor-amidites of 9-[2-deoxy-5-O-(4,4′-dimethoxytrityl)-2-methoxalylamino-β-D-ribofuranosyl]-and 9-[2-deoxy-5-O-(4,4′-dimethoxytrityl)-2-methoxalylamino-β-D-arabinofuranosyl]-N ⁶-benzoyladenine. The relative efficiency of the oligonucleotide synthesis with modified phosphoramidites was estimated. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1618–1624, September, 2006.     

Two new coumarin biosides from Angelica dahurica

Two new coumarin biosides, tert-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranosyl-byakangelicin (1) and 2′-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyl-peucedanol (2), were isolated from the fresh roots of Angelica dahurica. The structures of the new compounds were elucidated on the basis of spectral analysis. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 561–563, November–December, 2008.     

Flavonoid glycosides fromThalictrum squarrosum St. ex Willd. andThalictrum minus L.

Two flavonoid allose diglycosides were found in the terrestrial part ofThalictrum squarrosum St. ex Willd. andT. minus L. (Ranunculaceae). 7,4′-Di-O-β-allopyranosylapigenin was isolated fromT. minus. InT. squarrosum, its monoacetate was also found and characterized as 7-O-(6-O-acetyl-β-allopyranosyl)-4′-O-(β-allopyranosyl)apigenin. The sites of attachment of the carbohydrate residues were determined by HMBC; the location of the acetate group was identified by ROESY. Both substances were isolated from these plants for the first time. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 392–394, February, 1999.     

Synthesis of aminomethyl derivatives of sophoricoside

Aminomethylation of the natural isoflavonoid sophoricoside (genistein-4-O-β-D-glucoside) was studied. It was shown that the most convenient method for performing the aminomethylation was the use of aminals. 6,8-bis-Substituted derivatives of sophoricoside were synthesized.     

Alkylation of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with alkyl halides and dimethyl sulfate

Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH₂N(O)=NO⁻ M⁺ (R=Me, Prⁱ, or Bu^t; and M=Li, Na, K, Ag, NH₄, or Me₄N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH₂N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH₂N(NO)OR′. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998.