Antioxidant flavonoids from <Emphasis Type="Italic">Tamus communis</Emphasis> ssp. <Emphasis Type="Italic">cretica</Emphasis>

A new flavonoid, kaempferol-3,4′-di-O-α-L-rhamnopyranoside (1), and three known flavonoids (2–4) were isolated from the aerial parts of T. communis L. The structure of the new compound was elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed significant antioxidant activity (IC₅₀ 187.151 ± 0.821 μM, and 92.079±0.513 μM, respectively), whereas compounds 3 and 4 showed moderate activity in DPPH free radical scavenging assays. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 295–297, May–June, 2009.     

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.     

Novel <Emphasis Type="Italic">S</Emphasis>-containing lactones from monoterpene oxides

A new type of S-containing terpene lactones was produced by the reactions of limonene-1,2-oxide and β-pinene-α-oxide with mercaptoacetic acid. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 220–223, May–June, 2007.     

Triterpene glycosides from <Emphasis Type="Italic">Astragalus</Emphasis> and their genins. LXXXI. Chemical transformation of cycloartanes. VII. Synthesis of cyclosiversigenin lactone

The lactone 20R-25-norcycloartan-3β,6α,16β-triol-20,24-olide was synthesized from cyclosiversigenin. Presented at the 1st International Symposium on Edible Plant Resources and the Bioactive Ingredients, Xinjiang, China, July 25–27, 2008. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 324–327, May–June, 2009.     

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.     

Structure of a new xanthone from <Emphasis Type="Italic">Securidaca inappendiculata</Emphasis>

A new xanthone (1, 1,7-dihydroxy-2-methoxyxanthone), in addition to the known metabolites 1,7-dihydroxyxanthone (2), 24(R)-stigmast-7,22 (E)-dien-3α-ol (3), and 1,7-dimethoxyxanthone (4), was isolated from the roots of Securidaca inappendiculata. Compounds 1–4 were evaluated by anti-HIV assay and 1–3 showed anti-HIV-1inhibitory activity in vitro. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 348–349, July–August, 2008.     

Functionalization of <Emphasis Type="Italic">N-tert</Emphasis>-butoxycarbonyl-7-and <Emphasis Type="Italic">N-tert</Emphasis>-butoxycarbonyl-8-bromo-10-azabicyclo[4.3.1]deca-3,7-dienes. A route to a ferruginine homolog

N-tert-Butoxycarbonyl-7-and N-tert-butoxycarbonyl-8-bromo-10-azabicyclo[4.3.1]deca-3,7-dienes are convenient substrates for further modification using replacement of the Br atom by a cyano group or a Li atom. Treatment of lithium derivatives with dimethylformamide and N-methoxy-N-methylacetamide gave the corresponding α,β-unsaturated aldehydes (67–84%) and ketones (∼70%). Ketone 4b is a direct precursor of a homolog of the alkaloid ferruginine. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1794–1796, September, 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 from <Emphasis Type="Italic">Astragalus</Emphasis> and their genins. LXXX. Cyclomacroside D,a new bisdesmoside

The structure of the new cycloartane glycoside cyclomacroside D, which was isolated from Astragalus macropus Bunge (Leguminosae) and is 24R-cycloartan-1α,3β,7β,24,25-pentaol 3-O-α-L-rhamnopyranoside–24-O-β-D-xylopyranoside, was proved. Presented at the 7th International Symposium on the Chemistry of Natural Compounds (SCNC, Tashkent, Uzbekistan, October 16–18, 2007). Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 48–50, January–February, 2009.     

Essential Oil Composition of Four <Emphasis Type="Italic">Achillea</Emphasis> Species from the Balkans and Its Chemotaxonomic Significance

The chemical composition of the essential oils of Achillea clavennae L., Achillea holosericea Sibth. & Sm., Achillea lingulata W. & K., and Achillea millefolium L. from the Balkans was determined by GC and GC/MS analyses. The main components were 1,8-cineole in A. holosericea, camphor in A. clavennae, β-pinene in A. millefolium, and τ-cadinol in A. lingulata. A detailed chemotaxonomic discussion is presented. __________ Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 555–558, November–December, 2005.     

Glutinane triterpenes from the stem bark of <Emphasis Type="Italic">Euonymus hamiltonianus</Emphasis>

Three new glutinane-type triterpenes, 19α-glutin-5-en-19-ol (1), 2β,15α,21β-glutin-11-ene-2,15,21-triol (2), and 2β,19α-glutin-7,21-diene-2,19-diol (3), were isolated from the stem bark of Euonymus hamiltonianus. Their structures were determined by 1D and 2D NMR along with MS and IR. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 321–323, May–June, 2009.     

Degradation processes in the cellulose/<Emphasis Type="Italic">N</Emphasis>-methylmorpholine-<Emphasis Type="Italic">N</Emphasis>-oxide system studied by HPLC and ESR. Radical formation/recombination kinetics under UV photolysis at 77 K

Degradation processes of N-methylmorpholine-N-oxide monohydrate (NMMO), cellulose and cellulose/NMMO solutions were studied by high performance liquid chromatography (HPLC) and electron spin resonance (ESR) spectroscopy. Kinetics of radical accumulation processes under UV (λ = 248 nm) excimer laser flash photolysis was investigated by ESR at 77 K. Beside radical products of cellulose generated and stabilized at low temperature, radicals in NMMO and cellulose/NMMO solutions were studied for the first time in those systems and attributed to nitroxide type radicals ∼CH₂–NO^•–CH₂∼ and/or ∼CH₂–NO^•–CH₃∼ at the first and methyl ^•CH₃ and formyl ^•CHO radicals at the second step of the photo-induced reaction. Kinetic study of radicals revealed that formation and recombination rates of radical reaction depend on cellulose concentration in cellulose/NMMO solutions and additional ingredients, e.g., Fe(II) and propyl gallate. HPLC measurements showed that the concentrations of ring degradation products, e.g., aminoethanol and acetaldehyde, are determined by the composition of the cellulose/NMMO solution. Results based on HPLC are mainly maintained by ESR that supports the assumption concerning a radical initiated ring-opening of NMMO.     

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.     

Alkaloids from <Emphasis Type="Italic">Nitraria schoberi</Emphasis>. O-acetylnitraraine

The new alkaloid O-acetylnitraraine was isolated from the aerial part of Nitraria schoberi. Its structure was established using spectral data and chemical transformations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 472–473, September–October, 2005.     

The chemical composition of fruits of <Emphasis Type="Italic">Pistacia atlantica</Emphasis> desf. subsp. <Emphasis Type="Italic">atlantica</Emphasis> from Algeria

The chemical composition of the fruits of the north algerian ecotype Pistacia atlantica subsp. atlantica was determined and compared to other fruits of different species in the genus growing in south Algeria and other Mediterranean regions. These fruits were analyzed for their dry matter, protein, crude oil, ash, fatty acids, and phytosterol content. The main fatty acids identified by gas chromatography were oleic (54.15%), linoleic (28.84%), and palmitic (12.21%) acids. The fruits of the north ecotype were found to be rich in protein, oil, fiber, and unsaturated fatty acids, suggesting that they may be valuable for food uses. The sterols isolated were campesterol, stigmasterol, β-sitosterol, and Δ⁵-avenasterol with β-sitosterol as the major constituent (85%±0.85). The biochemical data indicated an elevated MUFA rate (∼56%) in pistacia oil which may be important against certain pathologies for its nutritional and preventive virtues. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 103–105, March–April, 2007.     

Microwave-Assisted Minutes Synthesis of Bioactive Phenylbutanoids Occurring in <Emphasis Type="Italic">Zingiber cassumunar</Emphasis>

Microwave-assisted condensation of benzaldehyde (3a,b) with acetone in aqueous sodium hydroxide adsorbed on basic alumina provides phenylbutenone (4a–4b) in 68–71% yield within 4 min, which upon further reduction with sodium borohydride and basic alumina gives phenylbutenol (5a,b) in 91–94% yield within 2 min. Dehydration of 5 with anhydrous copper (II) sulfate gives phenylbutadiene (1a,b), a metabolite of Zingiber cassumunar, within 3 min in 42–48% yield, respectively. All the steps involve environmental friendly solvents and reagents, mild reaction conditions, and overall formation of product 1a,b from 3a,b in 34–38% yield within 9 min under microwave irradiation. __________ Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 300–302, July–August, 2005.     

Triterpene glycosides from <Emphasis Type="Italic">Lonicera</Emphasis>. Isolation and structural determination of seven glycosides from flower buds of <Emphasis Type="Italic">Lonicera macranthoides</Emphasis>

The structures of seven triterpene glycosides (1–7), of which the 23-O-acetyl, 28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin 3-O-β-D-glucopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside (2) was new, from the flower buds of Lonicera macranthoides were established using chemical and NMR spectroscopic methods. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 32–34, January–February, 2008.     

Reaction of frangula-emodin with <Emphasis Type="Italic">α</Emphasis>-bromoalkylmethylketones

The alkylation of 1,6,8-trihydroxy-3-methylanthraquinone (frangula-emodin) by α-bromoalkylmethylketones was investigated. Hydroxyls in the 1-and 8-positions of the β-derivatives were O-acylated. The compositions and structures of the prepared compounds were confirmed by elemental analysis and UV, IR, PMR, and ¹³C NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 324–326, July–August, 2007.     

Lamiaceae carbohydrates. V. structure of glucoarabinogalactan from <Emphasis Type="Italic">Scutellaria baicalensis</Emphasis>

Chemical and spectral methods were used to establish that polysaccharide WSPS-3 isolated from the aerial part of Scutellaria baicalensis Georgi (Lamiaceae) was an acetylated glucoarabinogalactan, the main chain of which consisted of α-(1→6)-bonded galactopyranose with side chains consisting of arabinopyranose and partially acetylated glucopyranose residues located on C-2 and C-3. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 454–456, September-October, 2008.     

Excess molar enthalpies of the ternary system <Emphasis Type="Italic">p</Emphasis>-xylene+decane+diethyl carbonate

Excess molar enthalpies of the ternary system {x ₁ p-xylene+x ₂decane+(1–x ₁–x ₂)diethyl carbonate} and the involved binary mixtures {p-xylene+(1–x)decane}, {xp-xylene+(1–x)diethyl carbonate} and {xdecane+(1–x)diethyl carbonate} have been determined at the temperature of 298.15 K and atmospheric pressure, over the whole composition range, using a Calvet microcalorimeter. The experimental excess molar enthalpies H _m ^E are positive for all the binary systems studied over the whole composition range. Excess molar enthalpy for the ternary system is positive as well, showing maximum values at x ₁=0, x ₂=0.4920, x ₃=0.5080, H _m,123 ^E=1524 J mol^–1.