Isolation and GC-MS determination of flavonoids from Glycyrrhiza glabra root

Components of the ethylacetate extract of Glycyrrhiza glabra root were separated based on their acid-base properties. The major components of the fraction soluble in aqueous NaOH were identified by GC-MS as glabridin, the principal component of the ethylacetate extract of licorice root (Glycyrrhiza glabra L.), 4-O-methylglabridin, and hispaglabridin B. The isoflavene glabrin was identified in addition to the isoflavan derivatives. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 236–240, May–June, 2006.     

Dimeric prodelphinidins from Limonium gmelinii roots. III.

Two dimeric proanthocyanidines identified as 2R,3R,4R-(-)-epigallocatechin-(4β→ 8)-2R,3R-(-)-epigallocatechin-3-O-gallate and 2R,3R,4R-(-)-epigallocatechin-(4β→8)-(-)-2R,3R,3,5,7,3′,4′,6′-hexahydroxyflavan were isolated by adsorption chromatography over polyamide of the ethylacetate fraction of the aqueous alcohol extract of Limonium gmelinii roots. The former proanthocyanidine was isolated for the first time from sea lavender whereas the latter is new. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 134–138, March–April, 2006.     

Quantitative antioxidant activity of the ethylacetate extract of Larix sibirica bark and its individual components

The antioxidant [AO] properties of the ethylacetate extract of Larix sibirica bark and the flavonoids quercetin and dihydroquercetin found in it were studied using a model radical-chain oxidation of propan-2-ol in the kinetic regime. The quantitative characteristics of their AO activity were determined as effective rate constants fk_ln. It was found that dihydroquercetin had the highest AO activity among the studied natural compounds. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 131–133, March–April, 2006.     

Metabolites of the marine sponge <Emphasis Type="Italic">Suberites cf. aurantiacus</Emphasis>

Fractions of free sterols and sterol esters were observed in the ethylacetate extract of the marine sponge Suberites cf. aurantiacus and their compositions were determined. It was found that cholesterol was the predominant component in all sterol forms. The esters had a high content of unsaturated long-chain fatty acids (C₂₄–C₂₆). Sterol acetates have not been previously observed in marine invertebrates.     

A new component from <Emphasis Type="Italic">Eupatorium cannabinum</Emphasis>

A new compound of formula C₂₈H₄₈O with mp 179-180°C (aqueous ethanol) that was called eucanbin was isolated pure by column chromatography of the ethanol extract of the aerial part of Eupatorium cannabinum L. The structure 24α-methylcholest-20(21)-en-3β-ol was assigned based on chemical and spectral data. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–320, May–June, 2009.     

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.     

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.     

Extraction of metal ions (Fe<Superscript>3+</Superscript>, Co<Superscript>2+</Superscript>, Ni<Superscript>2+</Superscript>, Cu<Superscript>2+</Superscript> and Zn<Superscript>2+</Superscript>) using immobilized-polysiloxane iminobis(n-2-aminophenylacetamide) ligand system

A new insoluble solid functionalized ligand system bearing chelating ligand group of the general formula P-(CH₂)₃-N[CH₂CONH(C₆H₄)NH₂]₂, where P represents [Si–O] _n polysiloxane network, was prepared by the reaction of the immobilized diethyliminodiacetate polysiloxane ligand system, P-(CH₂)₃N(CH₂CO₂Et)₂ with 1,2-diaminobenzene in toluene. ¹³C CP-MAS NMR, XPS and FTIR results showed that most ethylacetate groups (–COOEt) were converted into the amide groups (–N–C=O). The new functionalized ligand system exhibits high capacity for extraction and removal of the metal ions (Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺) with efficiency of 95–97% after recovery from its primary metal complexes. This functionalized ligand system formed 1:1 metal to ligand complexes.     

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).     

Low-molecular-weight phenolic compounds from <Emphasis Type="Italic">Hedysarum theinum</Emphasis> roots

Isoflavonoids (−)-medicarpin, (−)-vestitol, formononetin, 8-hydroxydaidzein, and 6″-O-acetylononin were isolated for the first time in addition to (−)-catechin, (−)-epicatechin, protocatechoic acid, raspberry ketone, and rhododendrol from the alcohol extract of Hedysarum theinum roots. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 26–28, January–February, 2008.     

New alkaloids from <Emphasis Type="Italic">Casimiroa edulis</Emphasis> fruits and their pharmacological activity

The extract of Casimiroa edulis was investigated for antihypertensive activity. The ethanol and total alkaloids (in chloroform) extracts were found to have antihypertensive properties at doses of 500 and 200 mg/kg, respectively. Four quinolinone alkaloids were isolated and identified as: 2-(2′-hydroxy-4′-methoxyphenyl)-5,8-dimethoxy-3-propyl-1H-quinolin-4-one (1), 5,8-dimethoxy-2-(3′-methoxyphenyl)-3-propyl-1H-quinolin-4-one (2), 5,8-dimethoxy-2-(3′,4′-dimethoxyphenyl)-3-propyl-1H-quinolin-4-one (3), and 5,6-dimethoxy-2-(2′,5′,6′-trimethoxyphenyl)-1H-quinolin-4-one (4). Interestingly, compounds 1, 2, and 3 were found to be new alkaloids. The four isolated alkaloids showed antihypertensive activity at doses of 50, 100, 200, and 300 mg/kg, respectively. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 473–476, September–October, 2007.     

Sulfated steroid glycosides from the Viet Namese starfish <Emphasis Type="Italic">Linckia laevigata</Emphasis>

Five sulfated steriodal compounds including one new glycoside called linckoside L7 (1) and four previously known glycosides 2–5 were isolated from the starfish Linckia laevigata. The structure sodium (22E, 24R)-3-O-(2-O-methyl-β-D-xylopyranosyl)-29-O-(β-D-xylopyranosyl)-24-ethylcholest-4,22-dien-3β,6β,8,15α,16β,29-hexaol 15-O-sulfate was proposed for L7. Linckoside L7 inhibited fertilization and egg-cell development in the sea urchin Strongylocentrotus intermedius. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 64–67, January–February, 2007.     

Isolation of secoisolariciresinol diglucoside from lignan-containing extract of <Emphasis Type="Italic">Linum usitatissimum</Emphasis> seeds

An effective method for obtaining secoisolariciresinol diglucoside (SDG) purified of lignan from extract of Linum usitatissimum seeds was proposed. The lignan-containing concentrate obtained by aqueous ethanol extraction with microwave irradiation was purified using column chromatography. The structure of the compound was confirmed using IR, mass, and NMR spectra. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 21-23, January–February, 2009.     

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.     

Synthesis of 1,11,11-trimethyl-3,6-diazotricyclo [6.2.1.0<Superscript>2,7</Superscript>]undeca-2,6-diene and 1,15,15-trimethyl-3,10-diazotetracyclo[10.2.1.0<Superscript>2,11</Superscript>.0<Superscript>4,9</Superscript>]pentadeca-2,4(9),5,7,10-pentaene from camphoroquinone enantiomers

Optically active camphordihydro-2,3-pyrazine and camphorquinoxaline were prepared from camphoroquinone enantiomers. It was shown that (1S,4R)-(+)-camphoroquinone was formed by oxidation of (1S,3R, 4R)-(−)-3-bromocamphor and (1R,4S)-(−)-camphoroquinone from (1R,3S, 4S)-(+)-3-bromocamphor, respectively. Camphor anhydride was a side product (6–10%) of the reaction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–52, January–February, 2007.     

Composition of essential oil from <Emphasis Type="Italic">Artemisia glauca</Emphasis> from western Siberia

The composition of essential oil from Artemisia glauca (Asteraceae) growing in southern Siberia was studied. More than 60 oil components consisting of 99.0–99.7% of the total volatile components were identified by GC—MS by comparison of full mass spectra and retention times. The main components of the essential oil were acetylene derivatives of capillene (11–60%) and benzyldiacetylene (1–31%). Other acetylene derivatives such as capillin, (E)-hex-4-en-2-ynylbenzene, 1-(4-methoxyphenyl)-2,4-pentadiyne, and capillarin were also identified in the oil. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 446–449, September–October, 2007.     

Components of cyclohexane extract of <Emphasis Type="Italic">Anthemis triumfetti</Emphasis>

The cyclohexane extract of the aerial parts of Anthemis triumfetti (L.) DC. was analyzed by means of GC-MS to determine the fatty acid and sterol composition. Additionally, camphor, trans-phytol, squalene, and β-carotene were isolated and identified on the basis of their data. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 420–421, September–October, 2007.     

Lavandoside from <Emphasis Type="Italic">Lavandula spica</Emphasis> flowers

The new natural compound lavandoside with the structure ferulic acid 4-O-β-D-glucopyranoside was isolated by column chromatography over silica gel and polyamide from the extract of Lavandula spica flowers. The chemical structure of lavandoside was established using UV, NMR, and mass spectra and chemical transformations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 133–134, March–April, 2008.     

Xanthothone,a new nematicidal N-compound from <Emphasis Type="Italic">Coprinus xanthothrix</Emphasis>

Coprinus xanthothrix was found to have nematicidal activity. Xanthothone was isolated from culture extract guided by activity assay, which was identified as a novel natural product. Two other compounds were also isolated. These compounds showed nematicidal activity, with LD₅₀ value of 125–250 ppm both against Panagrellus redivivus and Meloidogyne incognita. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 161–162, March–April, 2008.     

Synthesis and structure of <Emphasis Type="Italic">N</Emphasis>-(2-(1-adamantyl)-2-hydroxyethyl)cytisine diastereomers

Diastereomers of N-(2-(1-adamantyl)-2-hydroxyethyl)cytisine were synthesized by reduction of N-(2-(1-adamantyl)-2-oxoethyl)cytisine with NaBH₄. Their structures were established using x-ray structure analysis. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 244–247, May–June, 2007.