Showing papers on "Xanthone published in 2008"
TL;DR: Bioactivity-guided fractionation of a dichloromethane-soluble extract of Garcinia mangostana fruits has led to the isolation and identification of five compounds, including two xanthones, 1,2-dihydro-1,8,10-trihydroxy-2-(2-hydroxypropan-2-yl)-9-(3-methylbut- 2-enyl)furo[3, 2-a].
107 citations
TL;DR: Investigations of the marine-derived fungus Chaetomium sp.
Abstract: Investigations of the marine-derived fungus Chaetomium sp. led to the isolation of the new natural products chaetoxanthones A, B, and C (1−3). Compounds 1 and 2 are substituted with a dioxane/tetrahydropyran moiety rarely found in natural products. Compound 3 was identified as a chlorinated xanthone substituted with a tetrahydropyran ring. The configurational analysis of these compounds employed CD spectroscopy, modified Mosher’s method, and selective NOE gradient measurements. Compound 2 showed selective activity against Plasmodium falciparum with an IC50 value of 0.5 μg/mL without being cytotoxic toward cultured eukaryotic cells. Compound 3 displayed a moderate activity against Trypanosoma cruzi with an IC50 value of 1.5 μg/mL.
81 citations
TL;DR: The hypothesis that several arylhydrazonomethyl derivatives synthesized from various isomeric 1,3-dihydroxyxanthone carbaldehydes could be endowed with a mechanism of action distinct to that of doxorubicin is proposed.
67 citations
TL;DR: It is noteworthy that oblongifolin C (4), the major constituent of this plant, has proved to be the most active one among the isolates for inducing apoptotic cell death in cervical cancer derived HeLa-C3 sensor cells.
Abstract: Bioassay and ultraperformance liquid chromatography/photodiode array/mass spectrometry (UPLC/PDA/MS) guided isolation of the apoptosis-inducing active metabolites on HeLa-C3 cells from the pericarp of Garcinia yunnanensis (Guttiferae) yielded five active compounds, including the new garciyunnanins A (1) and B (2). The structures of the compounds were elucidated by comprehensive nuclear magnetic resonance and mass spectrometry analysis. Garciyunnanin B (2), featured with a natural tetracyclic xanthone skeleton derived from a polyisoprenylated benzophenone, is structurally interesting since it can be seen as an evidence of the previously described cyclization of garcinol by 2,2-diphenyl-1-picrylhydrazyl (DPPH). Garciyunnanin A (1) contains a 3-monohydroxy benzophenone skeleton, which is rarely found in Garcinia species. Both new compounds induce HeLa-C3 cells into apoptosis after 72 h of incubation at 15 microM. It is noteworthy that oblongifolin C (4), the major constituent of this plant, has proved to be the most active one among the isolates for inducing apoptotic cell death in cervical cancer derived HeLa-C3 sensor cells.
67 citations
TL;DR: Oxy-guttiferone K is the first example of tetracyclic xanthone derived from the oxidation of a polyisoprenylated benzophenone from natural source and is in agreement with the previously described cyclization of garcinol by DPPH.
Abstract: In light of the wide range of biological activities of garcinol and with the aim of exploring some of them, we carried out its isolation from the fruits of Garcinia cambogia L. (Guttiferae). Surprisingly, the fruits were also found to contain guttiferones I, J, and K, compounds never reported in G. cambogia, along with three new compounds, namely, guttiferone M (1), guttiferone N (2), and the oxidized derivative of guttiferone K (6). Oxy-guttiferone K (6) is the first example of tetracyclic xanthone derived from the oxidation of a polyisoprenylated benzophenone from natural source. The natural formation of oxy-guttiferone K is in agreement with the previously described cyclization of garcinol by DPPH.
60 citations
TL;DR: Inhibitory activities of xanthone derivatives can be regulated by H-bond forming substituents, pi-stacking-forming aromatic rings and softness values on the xanthones skeleton.
50 citations
TL;DR: The metatrophic fungus Paecilomyces sp.
44 citations
TL;DR: Two new xanthones, 8‐(methoxycarbonyl)‐1‐hydroxy‐9‐oxo‐9H‐xanthene‐3‐carboxylic acid and 6‐dicarboxylate, were isolated from the culture broth of the mangrove fungus Penicillium sp.
Abstract: Two new xanthones, 8-(methoxycarbonyl)-1-hydroxy-9-oxo-9H-xanthene-3-carboxylic acid (1) and dimethyl 8-methoxy-9-oxo-9H-xanthene-1, 6-dicarboxylate (2) and one known xanthone methyl 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (3) were isolated from the culture broth of the mangrove fungus Penicillium sp. (ZZF 32#) collected from the South China Sea. Their structures were established by comprehensive analysis of one-dimensional (1D) and two-dimensional (2D) NMR data. The structure of compound 3 was confirmed by X-ray crystallography, which led to the suggestion that janthinone (4) might have the same structure as 3. Compounds 1–3 were inactive against KB or KBv200 cells during cytotoxicity evaluations. Copyright © 2008 John Wiley & Sons, Ltd.
44 citations
TL;DR: A series of appropriate alkanolamine and amide derivatives of xanthone were prepared and evaluated for anticonvulsant activity using maximal electroshock (MES) and subcutaneous pentylenetetrazole induced seizures, and for neurotoxicity (TOX) using the rotorod test on mice and rats.
33 citations
01 Jan 2008
31 citations
TL;DR: The study determined the minimum structure of GA for its apoptosis inducing activity, which could lead to the development of simple derivatives as potential anti-cancer drugs.
TL;DR: The phytochemical study of stem bark of Allanblackia gabonensis has resulted in the isolation and characterisation of one new xanthone derivative, named allanxanthone D, together with 10 known compounds, which were evaluated for their activity against Leishmania amazonensis in vitro and antimicrobial activities against a range of Gram negative and Gram positive bacteria.
TL;DR: A new caged polyprenylated xanthone, gambogic aldehyde (1 ), was isolated from the resin of Garcinia hanburyi.
TL;DR: A new prenylated xanthone N, together with two known constituents, gerontoxanthone C and 2-hydroxyxanthone, was isolated from the ethanolic extract of the twigs of Calophyllum inophyllums.
TL;DR: The structures of 1-3 were elucidated by spectroscopic methods including 1D and 2D NMR experiments as well as HRESIMS analysis.
Abstract: A new prenylated xanthone, pinetoxanthone (1), and two new pyranochromanones, pinetoric acid I (2) and pinetoric acid II (3), together with 10 known compounds, namely, the triterpenes friedelin and canophyllol, the xanthone macluraxanthone, the pyranochromanone derivatives calophyllic acid, isocalophyllic acid, calolongic acid, apetalic acid, and isoapetalic acid, and the flavonoids amentoflavone and apigenin, were isolated from the stem bark and leaves of Calophyllum pinetorum, an endemic species in Cuba. The structures of 1-3 were elucidated by spectroscopic methods including 1D and 2D NMR experiments as well as HRESIMS analysis.
TL;DR: For the first time, NMR studies for the heme-drug interactions are carried out at pH 5.0, physiological for the acidic food vacuole of the malaria parasite.
TL;DR: Two of them, the xanthone garciniaxanthone I and the triterpene, named garcinane, are reported as new natural products and the in vitro antimalarial activity of isoxanthochymol against Plasmodium falciparum shows strong chemosuppression of parasitic growth.
Abstract: Eight compounds were isolated from the roots of Garcinia polyantha, and identified. Two of them, the xanthone garciniaxanthone I (1), and the triterpene, named garcinane (2), are reported as new natural products. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR spectroscopic studies. The structure of compound 1 was confirmed by X-ray crystallography. Among the remaining six known compounds, three were known xanthones [smeathxanthone A (3), smeathxanthone B (4), and chefouxanthone (5)], one benzophenone [isoxanthochymol (6)], one triterpene [magnificol], and one sterol [beta-sitosterol]. The in vitro antimalarial activity of isoxanthochymol (6) against Plasmodium falciparum shows strong chemosuppression of parasitic growth.
TL;DR: Dulcisxanthone G, 1,3,6-trihydroxy-2-(2,3-dihydroxy-3- methylbutyl)-7-methoxy-8-(3-methyl-2-butenyl)xanth one, together with 13 known compounds were isolated from the seeds of Garcinia dulc isanthone.
TL;DR: In this paper, the stem bark of Allanblackia gabonensis has been used for the isolation and characterization of one new xanthone derivative, named allanxanthone D, together with ten known compounds, including 6-deoxyisojacareubin, one polyisoprenylated benzophenone, guttiferone F, one flavanol, epicathechin, two phytosterols, β-sitosterol and campesterol.
Abstract: The phytochemical study of the stem bark of Allanblackia gabonensis has resulted in the isolation and characterization of one new xanthone derivative, named allanxanthone D, together with ten known compounds, including six xanthone derivatives, allanxanthone A, 1,5-dihydroxyxanthone, 1,7-dihydroxyxanthone and 1,3,6,7-tetrahydroxy-2-(3-methylbut-2-enyl)xanthone, forbexanthone, 6-deoxyisojacareubin, one polyisoprenylated benzophenone, guttiferone F, one flavanol, epicathechin, two phytosterols, β-sitosterol, and campesterol. The structures of these compounds were established on the basis of one- and two-dimensional NMR homo- and heteronuclear evidence. These compounds were evaluated for their activity against Leishmania amazonensis in vitro and antimicrobial activities against a range of Gram-negative and Gram-positive bacteria.
TL;DR: In this article, a bis-xanthone with the xanthone-Xanthone linkage between an aromatic C-atom and a C5 side chain from a guttiferae plant, named garcinenone F (2), was isolated from the bark of Garcinia xanthochymus.
Abstract: A new bis-xanthone (xanthone=9H-xanthen-9-one), named bigarcinenone A (1) which is the first example of a bis-xanthone with the xanthone–xanthone linkage between an aromatic C-atom and a C5 side chain from a guttiferae plant, a new phloroglucinol (=benzene-1,3,5-triol) derivative, named garcinenone F (2), together with seven known xanthones were isolated from the bark of Garcinia xanthochymus. Their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques. Bigarcinenone A (1) exhibited potent antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging test with a IC50 value of 9.2 μM, compared to the positive control, the well-known antioxidant butylated hydroxytoluene (BHT) with a IC50 of 20 μM (Table 3).
TL;DR: A new xanthone, 1,8-dihydroxy-3-methoxy-6-methylxantone and a new polyketide derivative, (4R∗,5S∆,6E,8Z)-ethyl-4-((E)-but-1-enyl)-5-hydroxypentdeca-6, 8-dienoate, together with 20 known secondary metabolites, including 2 steroids, 4 xanthones, 10 anthraquinones, 2 triterpenoids, 1 fatty ester,
TL;DR: Two new xanthone antibiotics, citreamicin delta and epsilon, with potent activity against Gram-positive pathogens including multidrug-resistant Staphylococcus aureus (MDRSA) were discovered.
Abstract: Two new xanthone antibiotics, citreamicin delta (1) and epsilon (2), with potent activity against Gram-positive pathogens including multidrug-resistant Staphylococcus aureus (MDRSA) were discovered. Compounds 1 and 2 exhibited MIC values < 1 microg/mL versus a number of resistant strains. The compounds were obtained from EtOAc extracts of Streptomyces vinaceus and were purified by countercurrent chromatography and reversed-phase HPLC. Their structures were elucidated using primarily NMR and mass spectroscopy.
TL;DR: In this paper, a novel Zn(Π) xanthone-crown ether complex was synthesized and demonstrated to selectively detect HSO 4 -over other anions by fluorescence and UV-vis absorption spectroscopy.
TL;DR: In this paper, the mechanism of free-radical formation was established using the laser flash photolysis, and the photoinitiation ability of the xanthone or thioxanthone-derivative/ amino acid or sulfur-containing amino acid pairs depends on the initiator and co-initiator properties.
Abstract: Photoredox pairs, composed of xanthone or thioxanthone derivatives acting as light absorbers and tetrabutylammonium salts of amino acids or sulfur-containing amino acids as co-initiators, were studied as photoinitiators for free-radical polymerization. The mechanism of free-radical formation was established using the laser flash photolysis. Measurements of polymerization kinetics show that the photoinitiation ability of the xanthone- or thioxanthone-derivative/ amino acid or sulfur-containing amino acid pairs depends on the initiator and co-initiator properties, mostly on the triplet state lifetime of xanthone or thioxanthone derivatives.
TL;DR: In this paper, the contents of five pharmacologically active flavone and xanthone glycosides extracted from Tibetan folk medicinal species Swertia mussotii and S. franchetiana were determined by capillary electrophoresis with diodearray detection.
Abstract: The contents of five pharmacologically active flavone and xanthone glycosides, namely, swertianolin, swertisin, isoorientin, mangiferin, and 7-O-[α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranosyl]-1,8-dihydroxy-3-methoxyxanthone, extracted from Tibetan folk medicinal species Swertia mussotii and S. franchetiana were determined by capillary electrophoresis with diode-array detection. The separation of five components has been optimized with a capillary column with a total length of 48.5 cm and effective length of 40 cm (50 μm i.d). The influence of the running buffer, the sodium dodecyl sulfonate (SDS) concentration, organic modifier, etc. on the resolution was evaluated. The background electrolyte contained 30 mM borate buffer, 28 mM SDS, 1.0% (v/v) acetonitrile, and was adjusted to pH 9.0 with 0.1 M NaOH. A good baseline resolution was obtained for the separation of five components within 5 min with the working voltage of 24 kV and a column temperature of 25°C. The established method was rapid and reproducible for the separation and determination of five flavone and xanthone glycosides from the extracts of S. mussotii and franchetiana plant samples.
TL;DR: A new xanthone derivative having axial chirality was isolated from Penicillium vinaceum and has a structure containing two aromatic moieties with substituents hindering rotation about the biaryl axis.
Abstract: A new xanthone derivative having axial chirality was isolated from Penicillium vinaceum. Owing to the axial chirality, its structure, including absolute configuration, was determined by means of extensive spectroscopic data, such as UV, IR, MS, and 1D and 2D NMR spectra, and computational chiroptical methods. The new compound, (aR)-2′-methoxyvinaxanthone, has a structure containing two aromatic moieties with substituents hindering rotation about the biaryl axis. The compound gave positive results in a sea urchin egg test (Paracentrotus lividus) and a crown gall tumor on potato disks test (Agrobacterium tumefaciens).
TL;DR: The antioxidant in vitro activities of 1–6 were determined by the scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and hydroxyl radicals and their reductive activities to Fe3 + .
TL;DR: A new xanthone (1, 1, 7-dihydroxy-2methoxyxanthone) was isolated from the roots of Securidaca in appendiculata as discussed by the authors.
Abstract: 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.
Journal Article•
TL;DR: To study xanthones from the barks of Garcinia xanthochymus, the constituents were isolated by normal-phase and reverse-phase silica gel column chromatography from the EtOAc extract and their structures were elucidated by spectral analysis.
Abstract: To study xanthones from the barks of Garcinia xanthochymus, the constituents were isolated by normal-phase and reverse-phase silica gel column chromatography from the EtOAc extract Their structures were elucidated by spectral analysis Three new xanthones were purified and identified as 1,2,5-trihydroxy-6-methoxyxanthone (1), 1,4,6-trihydroxy-5-methoxyxanthone (2), 1,2,7-trihydroxy-4-(1,1-dimethylallyl) xanthone (3)