Glucofructans from <Emphasis Type="Italic">Saussurea lappa</Emphasis> roots

Glucofructans from Saussurea lappa (Asteraceae) roots were studied. It was found that free fructose and oligomeric glucofructans (saccharose, 1-kestose, nystose, 1^F-β-fructofuranosylnystose, and 1^F-β-fructofuranosyl-1^F-β-fructofuranosylnystose) were present. The dominant polymer Sl-GF (MW 51.4 kDa), which was a linear inulin-type glucofructan consisting of β-(2 → 1)-bonded fructofuranose units, was isolated and characterized. The total content of glucofructans in Saussurea lappa roots was 476.97–578.27 mg/g.     

Polysaccharides from Fabaceae. V. <Emphasis Type="Italic">α</Emphasis>-Glucan from <Emphasis Type="Italic">Sophora flavescens</Emphasis> roots

Water-soluble polysaccharides from Sophora flavescens (Fabaceae) roots were studied. The dominant polymer S _f P-1-1/2 of molecular weight 85 kDa was isolated using ion-exchange and gel chromatography. The structure of the isolated compound was α-(1→4)-glucan partially substituted at the C-6 position by single glucopyranose units. A pharmacological study showed that S _f P-1-1/2 exhibited under azathioprine suppression pronounced immunostimulating activity.     

Quantitative1H and13C NMR spectroscopy of lignins isolated from aspen wood by various methods

A comparative analysis has been made of the chemical structures of aspen milled wood lignin, aspen dioxane lignin, and lignin from the explosive autohydrolysis of aspen wood.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 878–886, November–December, 1995. Original article submitted November 22, 1994.     

Nanosized hydrogenation catalyst based on palladium bisacetylacetonate and phosphine: Formation,the origin of activity,and properties

The nature and catalytic properties of a hydrogenation catalyst based on Pd(acac)₂ and PH₃ are considered. As demonstrated by a variety of physicochemical methods (IR and UV spectroscopy, ³¹P and ¹H NMR, electron microscopy, and X-ray powder diffraction), nanoparticles consisting of various palladium phosphides (Pd₆P, Pd_4.8P, and Pd₅P₂) and Pd(0) clusters form under the action of dihydrogen during catalyst preparation. The promoting effect of phosphine at low PH₃: Pd(acac)₂ ratios is mainly due to the ability of phosphine to increase the extent of dispersion of the catalyst.     

Reaction of Palladium Bis(acetylacetonate) with Diphenylphosphine: Spectral Studies

Interaction of palladium bis(acetylacetonate) with diphenylphosphine is studied by NMR, IR, and UV methods. Reaction between reagents taken in equimolar amounts gives binuclear and trinuclear palladium complexes with bridging diphenylphosphide and the chelate acetylacetonate [Pd(Acac)PPh₂]₂ and [Pd₃(Acac)₂(PPh₂)₄] ligands. With excess PPh₂H, the trinuclear palladium complex, whose composition is supposed to be [Pd₃(PPh₂)₄(PPh₂–PPh₂) · C₆H₆], is isolated and characterized on the basis of the spectral data.     

Chemical composition of <Emphasis Type="Italic">Aloe arborescens</Emphasis> and its change by biostimulation

The chemical composition of Aloe arborescens Mill. (Asphodelaceae) and its change by biostimulation (cold stress) were studied. It was found that aloe-emodin; 2′′-O-feruloylaloesin; aloins A and B; aloenin; free glucose, saccharose, and fructose; pectinic substances; and malic, malonic, and oxalic acids were present. 4-Methoxy-6-(4′-hydroxy6′-methylphenyl)-2-pyrone, 7-hydroxy-2,5-dimethylchromone, umbeliferone, esculetin, and vanillic and veratric acids were found for the first time. Changes in the chemical composition of A. arborescens due to biostimulation for 5-10 d increased the antiradical and biostimulating activity of the raw material.     

Lamiaceae carbohydrates. VI. Water-soluble polysaccharides from <Emphasis Type="Italic">Lophanthus chinensis</Emphasis>

The composition of water-soluble polysaccharides from the aerial part of Lophanthus chinensis Benth. (Lamiaceae) was studied. The dominant polymer LCW_H-2, which was a partially acetylated glucoarabinogalactan, the main chain of which was constructed of α-(1→6)-bonded galactopyranose, was isolated and characterized. Atoms C-2 and C-3 of the main chain had branches of single glucopyranose and arabinopyranose units and short chains of (1→3)-bonded arabinose. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 258–260, May–June, 2009.