Monodictyquinone A: a new antimicrobial anthraquinone from a sea urchin-derived fungus Monodictys sp

A new antimicrobial anthraquinone, 1,8-dihydroxy-2-methoxy-6-methylanthraquinone, monodictyquinone A (1), was isolated from a culture of a marine-derived fungus of the genus Monodictys which was isolated from the sea urchin, Anthocidaris crassispina, along with three known compounds, pachybasin (2), chrysophanol (3), and emodin (4).     

One new anthraquinone from marine Streptomyces sp. FX-58

One new anthraquinone, 1,8-dihydroxy-2-ethyl-3-methylanthraquinone (1), together with two known compounds octadecanoic acid (2) and cholest-4-en-3-one (3) was isolated from marine actinomycete Streptomyces sp. FX-58. The structure of 1 was elucidated on the basis of spectroscopic methods, especially, the 2D-NMR spectral analysis. The cytotoxic activities of 1 were evaluated in vitro.     

Analysis of anthraquinones in Rumex crispus by micellar electrokinetic chromatography

A micellar electrochromatographic method was performed for the analysis of the pharmaceutically important anthraquinones from the root of Rumex crispus. The separation of 1,5-dihydroxy-3-methylanthraquinone (1); 1,3,5-trihydroxy-6-hydroxymethylanthraquinone (2); 1,5-dihydroxy-3-methoxy-7-methylanthraquinone (3) was achieved in 6 min using a running buffer containing 10 mmol/l sodium borate, 50 mmol/l sodium dodecylsulfate, and 25% acetonitrile at pH 10.6. The method is simple, rapid, and reproducible.     

Mutagenicity of Tectona grandis Wood Extracts and Their Ability to Improve Carbohydrate Yield for Kraft Cooking Eucalyptus Wood

Considering the toxicity of the impurities of synthesized anthraquinone, this study clarified new catalytic compounds for kraft cooking with improved carbohydrate yield and delignification and less mutagenicity, which are important for ensuring the safety of paper products in contact with food. The 2-methylanthraquinone contents of teak (Tectona grandis) woods were 0.18–0.21%. Acetone extracts containing 2-methylanthraquinone from Myanmar and Indonesia teak woods as additives improved lignin removal during kraft cooking of eucalyptus wood, which resulted in kappa numbers that were 2.2–6.0 points lower than the absence of additive. Myanmar extracts and 2-methylanthraquinone improved carbohydrate yield in pulps with 1.7–2.2% yield gains. Indonesia extracts contained more deoxylapachol and its isomer than 2-methylanthraquinone. The residual content of 2-methylanthraquinone in the kraft pulp was trace. Although Ames tests showed that the Indonesia and Myanmar extracts were mutagenic to Salmonella typhimurium, 2-methylanthraquinone was not. The kraft pulp obtained with the additives should be safe for food-packaging applications, and the addition of 0.03% 2-methylanthraquinone to kraft cooking saves forest resources and fossil energy in industries requiring increased pulp yield.     

Comparative evaluation of two Trichoderma harzianum strains for major secondary metabolite production and antifungal activity

This investigation was undertaken to identify the major secondary metabolite, produced by two Trichoderma harzianum strains (T-4 and T-5) with their antifungal activity against phytopathogenic fungi using poison food technique. The ethyl acetate extract was subjected to column chromatography using n-hexane, ethyl acetate and methanol gradually. Chromatographic separation of ethyl acetate extract of T. harzianum (T-4) resulted in the isolation and identification of palmitic acid (1), 1,8-dihydroxy-3-methylanthraquinone (2), 6-pentyl-2H-pyran-2-one (3), 2(5H)-furanone (4), stigmasterol (5) and β-sitosterol (6), while T. harzianum (T-5) gave palmitic acid (1), 1-hydroxy-3-methylanthraquinone (7), δ-decanolactone (8), 6-pentyl-2H-pyran-2-one (3), ergosterol (9), harzianopyridone (10) and 6-methyl-1,3,8-trihydroxyanthraquinone (11) as major metabolites. Among compounds screened for antifungal activity, compound 10 was found to be most active (EC₅₀ 35.9–50.2 μg mL^? 1). In conclusion, the present investigation provided significant information about antifungal activity and compounds isolated from two different strains of T. harzianum obtained from two different Himalayan locations.     

A new anthraquinone from Galium verum L

A new anthraquinone (4) and three known anthraquinones (1-3) were isolated from Galium verum L. Their structures were identified as 1,3-dihydroxy-2-methylanthraquinone (1), physcion (2), 2-hydroxy-1,3-dimethoxyanthraquinone (3), 2,5-dihydroxy-1,3-dimethoxyanthraquinone (4) by means of chemical and spectroscopic analysis. Compound 2 was isolated from the genus Galium for the first time. In addition, compound 4 was assayed for antimicrobial activity in vitro.     

Anthraquinone derivatives from Micromonospora rhodorangea

From the fermentation broths of the actinomycete Micromonospora rhodorangea, four anthraquinone derivatives (1-4) were isolated, of which 2-ethyl-1,8-dihydroxy-3-methyl-anthraquinone (1) and 3,8-dihydroxy-1-propylanthraquinone (3) were determined as new compounds. Their structures were established by using extensive spectroscopic data analyses. 2-ethyl-1-hydroxy-8-methoxy-3-methyl anthraquinone (2) was isolated from actinomycetes for the first time and its NMR data was assigned.     

Isolation and characterisation of three new anthraquinone secondary metabolites from Symplocos racemosa

Three new anthraquinone secondary metabolites were isolated from Symplocos racemosa, a small tree of family symplocaceae. The structures of compounds (1–3) were elucidated to be 1,4-dihydroxy-6-(ethoxymethyl)-8-propylanthracene-9,10-dione (1), 1,4-dihydroxy-6-(hydroxymethyl)-8-butylanthracene-9,10-dione (2) and 1,4-dihydroxy-6-(hydroxymethyl)-8-propyl anthracene-9,10-dione (3) using their spectral data, i.e. through IR, UV, ¹H NMR, ¹³C NMR and two-dimensional (2D) NMR techniques including heteronuclear multiple quantum coherence, heteronuclear multiple bond correlation and correlation spectroscopy.     

Determinazione di alcuni composti ossiantrachinonici a mezzo di titolazione in solventi non acquosi

Riassunto E stato applicato il metodo di titolazione potenziometrica con metilato sodico a composti fenolici aventi formula simile come l'1–8 diossiantrachinone, l'1–8 diossi-3-metilantrachinone e l'1–8 diossi-3-metil antrone, di notevole importanza farmaceutica.Come solvente si è usata la piridina e come rivelatori del punto di equivalenza una coppia di elettrodi vetro-antimonio non essendo possibile usare indicatori data la forte colorazione delle soluzioni.

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Summary Potentiometric titration with sodium methylate was used ton determine derivatives whose constitution is similar to that of 1,8-dihydroxyanthraquinone, 1,8-dihydroxy-3-methylanthraquinone and l,8-dihydroxy-3-methylanthrone.The solvent is pyridine. The change point was determined by means of an electrode pair: glass electrode-antimony electrode, since the intense self-color of the solutions excludes the use of indicators.

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Zusammenfassung Die potentiometrische Titration mit Natriummethylat wurde zur Bestimmung von Derivaten herangezogen, deren Zusammensetzung dem 1,8-Dihydroxyanthrachinon, dem 1,8-Dihidroxy-3-methylanthrachinon und dem 1,8-Dihidroxy-3-methylanthron ähnlich ist.Als Lösungsmittel wird Pyridin verwendet. Der Umschlagspunkt wird mit Hilfe eines Elektrodenpaares Glaselektrode-Antimonelektrode festgestellt, da die starke Eigenfärbung der Lösungen den Gebrauch von Indikatoren ausschließt.

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Résumé Le titrage potentiométrique par le méthylate de sodium a été appliqué au dosage de dérivés dont la composition est semblable à celles de la 1, 8-dihydroxyanthraquinone, de la 1,8-dihydroxy-3-méthylanthraquinone et de la l,8-dihydroxy-3-méthylanthrone. On utilise la pyridine comme solvant.Le point final de titrage est déterminé à l'aide d'un système électrode de verre: électrode d'antimoine car la forte coloration des solutions interdit l'emploi d'indicateurs.

     

Isolation and identification of new anthraquinones from Rhamnus alaternus L and evaluation of their free radical scavenging activity

From the butanolic and the ethyl acetate extracts of Rhamnus alaternus L root bark and leaves, three new anthraquinone glycosides, alaternosides A-C (1,4,6,8 tetrahydroxy-3 methyl anthraquinone 1-O-ß-D-glucopyranosyl-4,6-di-O-α-L-rhamnopyranoside (1); 1,2,6,8 tetrahydroxy-3 methyl anthraquinone 8-O-ß-D-glucopyranoside (2) and 1, 6 dihydroxy-3 methyl 6 [2′-Me (heptoxy)] anthraquinone (3)) were isolated and elucidated together with the two known anthraquinone glycosides, Physcion-8-O-rutinoside (4) and emodin-6-O-α-L-rhamnoside (5) as well as with the known kaempferol-7-methylether (6), β-sitosterol (7) and β-sitosterol-3-O-glycoside (8). Their chemical structures were elucidated using spectroscopic methods (1D-, 2D-NMR and FAB-MS). Free radical scavenging activity of the isolated compounds was evaluated by their ability to scavenge DPPH^. free radicals. Compounds (3), (4) and (6) showed the highest activity with IC₅₀ values of 9.46, 27.68 and 2.35 μg/mL, respectively.     

微量热法研究蒽醌化合物的抑菌活性和毒理作用

The growth therrnogenic curves of Staphylococcus aureus and Tetrahymena thermophila affected by 1,8-dihydroxyanthraquinone, emodin and rhein were determined quantitatively by microcalorimetry. The inhibitory effects of the three anthraquinones （AQ） on S. aureus revealed that the sequence of antimicrobial activity of those was rhein〉emodin〉 1,8-dihydroxyanthraquinone. The toxicity of the three AQ on T. thermophila indicated that all the tested AQ were toxic to the tested protozoa and the hydroxyl and carboxyl substituted at different position of anthraquinone ring resulted in the enhancement of toxicity.     

Analysis of Metabolites of Anthraquinones by Human Fecal Bacteria Using UPLC-Q-TOF-HRMS/MS

This study aimed to investigate the metabolism of anthraquinones, including chrysophanol (1), rhein (2), aloe-emodin (3), emodin (4), sennoside A (5) and sennoside B (6), by mixed human fecal bacteria to clarify the relationship between their chemical structural characteristics and intestinal metabolism. Six parent compounds were incubated with mixed human fecal bacteria in vitro to study the metabolic process. A highly sensitive and specific ultra-performance liquid chromatography-quadrupole time-of-flight high-resolution tandem mass spectrometry (UPLC-Q-TOF-HRMS/MS) with MS^E technology and MetaboLynx software has been developed to analyze the metabolites of anthraquinones. With this method, a total of ten metabolites were identified, including 1,4,8-trihydroxy-3-hydroxymethylanthraquinone (M1), 2-methylrhein (M2), 7-methylrhein (M3), methyl-esterificated rhein (M4), 1,8-dihydroxy-3-hydroxymethyl-4-methylanthraquinone (M5), physcion (M6), sennidin A (M7), rhein (M8), sennidin B (M9) and rhein (M10), six (M1–M6) of which were first detected on the basis of the exact mass by mixed human fecal bacteria in this work. The metabolism of anthraquinones occurred via hydroxylation, oxidation, methylation, deglycosylation and esterification. In particular, the methyl-esterificated rhein (M4) was first identified as one of the metabolites of rhein, whose metabolic pathway (esterification) is also reported for the first time. The presence of human fecal bacteria played a vital role in the metabolism of anthraquinones and the substitutional groups determined the different metabolic reactions for anthraquinones, which will be useful for the investigation of the study of anthraquinones in vivo.

     

Isolation and identification of anthraquinones of Caloplaca cerina and Cassia tora

Five hydroxyanthraquinone derivatives physcion, emodin, fallacinal, teloschistin, and 1,3-dimethoxy-8-hydroxy-6-methyl-9,10-anthraquinone were isolated from the lichen Caloplaca cerina growing in Serbia. Three anthraquinone derivatives, namely physcion, emodin, and rhein were isolated and identified from the Thai medicinal plant Cassia tora. Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May 2006.     

Contribution à la phytochimie du genre Gentiana,XVIII. Structure du gentiabavarutinoside,un nouveau glycoside xanthonique acylé isolé de Gentiana bavaricaL

Phytochemistry of genus Gentiana, XVIII: Structure of gentiabavarutinoside, a new acylated xanthone glycoside from Gentiana bavarica L. In a previous work [1], we isolated from Gentiana bavarica L . an acylated xanthone glycoside (1,8-dihydroxy-3-methoxy-xanthone-7-O-acetylrutinoside 1 or gentiabavarutinoside) without locating the acetyl group. By ¹³C-NMR. spectroscopy, the attach position of the acetyl is now shown to be at 4 of the rhamnose moiety. In addition, a new compound ( 2 ), the desacetyl derivative of 1 , has also been isolated and identified.     

peri-Naphthylenediamines

The reaction of 1,8-bis(dimethylamino)naphthalene (“proton sponge”) with trifluoroacetic anhydride afforded new derivatives of naphtho[1,8-c,d]pyran,viz., trans-) (4) andcis-1,3-dihydroxy-6,7-bis(dimethylamino)-1,3-bis(trifluoromethyl)-1H,3H-naphthol[1,8-c,d]pyran (5) and symmetrical 3,4,10,11-tetrakis(dimethylamino)-7,14-bis(trifluoromethyl)-7,14-epoxydinaphtho[1,8-a,b;1′, 8′-ef]cyclooctane (3), which belongs to a new type of double “proton sponges,” along with the expected 1,8-bis(dimethylamino)-4-trifluoroacetylnaphthalene. The structures of compounds3 and4 were established by spectral studies and X-ray diffraction analysis.     

Novel Trinor-eremophilanes (Dendryphiellin B,C, and D), Eremophilanes (Dendryphiellin E,F, and G), and Branched C9-Carboxylic Acids (Dendryphiellic Acid A and B) from the Marine Deuteromycete Dendryphiella salina (SUTHERLAND) PUGHet NICOT

Further investigation of global extracts from cultures of the marine deuteromycete Dendryphiella salina leads to the isolation of three novel trinor-eremophilanes esterified by branched C₉-carboxylic acids, dendryphiellin B (= (+)-(1R*,2S*,7R*,8aR*)-1,2,6,7,8,8a-hexahydro-7-hydroxy-1,8a-dimethyl-6-oxonaphthalen-2-yl (6R*, 2E, 4E)-6-hydroxy-6-methylocta-2,4-dienoate; (+)- 2 ), dendryphiellin C (=(+)-(1R*, 2S*, 7R*, 8aR*)-1,2,6,7,8,8a-hexa-hydro-7-hydroxy-1,8a-dimethyl-6-oxonaphthalen-2-yl (6S, 2E, 4E)-6-methylocta-2,4-dienoate; (+)- 3 )), and dendryphiellin D (=(+)-(1R*, 2S*, 7R*, 8aR*)-1,2,6,7(8,8a-hexahydro-7-hydroxy-1,8a-dimethyl-6-oxonaphthalen-2-yl (6R*,2E,4E)-6-(hydroxymethyl)octa-2,4-dienoate; (+)- 4 ). An intact eremophilane, dendryphiellin E ( 5 ), and its ethanolysis product dendryphiellin F whose absolute configuration is represented by structural formula (+)- 6 are also isolated from the above extracts. Dendryphiellin E exists as an open form 5a in equilibrium with a closed form 5b . A similar equilibrium exists between the open form 8a and the closed form 8b of a non-esterified eremophilane, dendryphiellin G ( 8 ), which is isolated too from the above extracts and proves structurally related to the cyclic portion of 5 . Finally, the free, branched C₉-carboxylic acids dendryphiellic acid A ((+)- 9 ) and B ((+)- 10 ) which correspond to side chains of the above esterified terpenes are also isolated from the above extracts.     

Identification de xanthones et de nouveaux arabinosides de C-glucosides flavoniques dans Swertia perennisL.

Identification of xanthones and new arabinosides of flavone C-glucosides from Swertia perennis L. – Seven tetraoxygenated xanthones [1,3,7,8-tetrahydroxy-xanthone ( 1 ); 1,8-dihydroxy-3,7-dimethoxy-xanthone ( 2 ); 1,7-dihydroxy-3,8-dimethoxy-xanthone ( 3 ); 1-hydroxy-3,7,8-trimethoxy-xanthone ( 4 ); 3,7,8-trihydroxy-xanthone-xanthone-1-0-β-glucoside ( 5 ); 3,7,8-trimethoxy-xanthone-1-0-primeveroside ( 6 ); 8-hydroxy-3,7-dimethoxy-xanthone-1-0-primeveroside ( 7 )] have been isolated chromatographically, using polyamide columns, from roots of Swertia perennis L . From leaves and stems of the same plant, six xanthones [1,5,8-trihydroxy-3-methoxy-xanthone ( 8 ); 1,5-dihydroxy-3-methoxy-xanthone-8-0-β-glucoside ( 9 ); mangiferin ( 10 ); 1 ; 4 ; 5 ] and four flavone C-glycosides [iso-orientin ( 11 ); isovitexin ( 12 ); iso-orientin-6″-arabinoside ( 13 ); isovitexin-6″-arabinoside ( 14 )] have also been isolated. Among these compounds, 7 , 13 and 14 were not encountered before in nature. In the last two compounds, the position of arabinose on the C-glucoside moiety of the flavone was established by ¹³C-NMR. spectroscopy.     

Decolorization Reactions Between Chromium (VI) and Three Colour Reagents. Determination of Chromium (VI) by Flow Injection Analysis

Abstract

Chromium (VI) can oxidize and decolor three colour reagents, i.e. 1,8-dihydroxy-2-(4′-chloro-2′-phosphonophenylazo)-7-(6″.8″-disulfonaphthylazo)-3,6-disulfonaphthalene (RI): 1,8-dihydroxy-2-(4′-chloro-2′-phosphonophenylazo)-7-(4″-sulfonamidephenylazo)-3,6-disulfonaphthalene (RII): and 1,8-dihydroxy-2-(4′-chloro-2′-phosphonophenylazo)-7-(p-hippuric acid azo)-3,6-disulfonaphthalene (RIII). Loss of absorbance of three colour reagents at maximum absorption wavelengths is proportional to the concentration of chromium (VI) in solution. We have made use of the decolorization reactions between chromium (VI) and three colour reagents to determine chromium in steel by flow injection analysis, and relative error in sample determination is less than 5.0%. Response is linear from 0.84 to 6.72 μg/mL and optimum measuring acidity is 1.3–1.7 mol/L H₂SO₄ in three systems. The effect of interference ions on determination has been studied.     

Two new monoterpenoid glycosides from the fresh rhizome of Tongling White Ginger (Zingiber officinale)

Two new monoterpenoid glycosides, trans-1,8-cineole-3,6-dihydroxy-3-O-β-D-glucopyranoside (1), and 5,9-dihydroxy borneol 2-O-β-D-glucopyranoside (2), together with four known monoterpenoid glycosides (3–6), were isolated from the water-soluble constituents of the fresh rhizome of Tongling White Ginger (Zingiber officinale). Their structures were decisively elucidated by spectroscopic analysis. In vitro tests for antimicrobial activity showed that compounds 1 and 3 possess significant activity against two Gram-positive organisms, Staphylococcus aureus and Staphylococcus epidermidis.     

Biological activities,phenolic profiles and essential oil components of Tanacetum cilicicum (BOISS.) GRIERSON

Tanacetum species are consumed as tea in Turkey. We comparatively evaluated the phytochemical potentials and antioxidant activities of the essential oil and methanolic extracts of Tanacetum cilicicum. The chemical constitutes of T. cilicicum essential oil and antioxidant activity of this species was analysed by gas chromatography–mass spectrometry (GC–MS) method. Bicyclo (3,1,1) hept-2-en-4-ol (21.92%), camphor (15.56%) and 1,8-cineole (13.45%) which are oxygenated monoterpenes were found as the major constituents. Phenolic acids and flavonoids were quantificated by HPLC–UV. Catechin was found as the main component. The essential oils and methanolic extracts were evaluated by antioxidant activities. The leaves exhibited significant metal chelation activity with a value of 20.75 ± 4.63 μg/mL.