Naturally occurring pentaoxygenated, hexaoxygenated and dimeric xanthones: a literature survey

Three new metabolites, microsphaeropsones A-C (1-3) with a unique oxepino[2,3-b]chromen-6-one (ring-enlarged xanthone) skeleton, were isolated from the endophytic fungus Microsphaeropsis species, co-occurring with their putative biogenetic anthraquinoide precursors citreorosein (4) and emodin (5). From another Microsphaeropsis species, large amounts of fusidienol A (8 a), smaller amounts of emodin (5), the known aromatic xanthones 9 a and 9 b, the new 3,4-dihydrofusidienol A (8 b), and the new aromatic xanthone 9 c were isolated. The endophyte Seimatosporium species produced a new aromatic xanthone, seimatoxanthone A (10), and 3,4-dihydroglobosuxanthone A (12), closely related to alpha-diversolonic ester (13) from Microdiplodia sp.. The structures were determined mainly by extensive 1D and 2D NMR experiments and supported by X-ray single-crystal analysis of 1 and the oxidation product 7. The absolute configurations of the microsphaeropsones A-C (1-3) were established by comparison of the electronic and vibrational circular dichroism (ECD and VCD) spectra of 1 with time-dependent DFT (TDDFT) and DFT calculations by using either the solid-state structures or DFT-optimized geometries as inputs. Preliminary studies indicated that 1, 2, and enone 7 showed antibacterial, fungicidal, and algicidal properties.

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“…Its molecular formula was established as C 16 Figure 5. TDDFT-calculated ECD spectra of the solid-state structure of (1R,2R)-1 (BH&HLYP/TZVP).…”

Section: Resultsmentioning

confidence: 99%

“…Xanthones and partially hydrogenated di-or tetrahydroxanthones are widespread classes of natural products [2] with considerable bioactivity [3][4][5][6][7][8][9][10][11] that occur in fungi, [9,[12][13][14] plants, [15][16][17][18] ferns, [19] and lichens. [20,21] Due to their pronounced toxicity, they are classified as mycotoxins.…”

Section: Introductionmentioning

confidence: 99%

Xanthones and Oxepino[2, 3‐b]chromones from Three Endophytic Fungi

Krohn

Kouam

Kuigoua

et al. 2009

Chemistry A European J

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“…[21], are isolated from two Centaurium species and 3-hydroxy-1,2,5,6,7-pentamethoxyxanthone was isolated from the roots of Polygala japonica. The natural occurrence of pentaoxygenated, hexaoxygenated, and dimeric xanthones has been reviewed by Peres and Nagem [22].…”

Section: Tetraoxygenated Xanthonesmentioning

confidence: 99%

Naturally Occurring Xanthones: Chemistry and Biology

Negi

Bisht

Singh

et al. 2013

Journal of Applied Chemistry

164

120

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Xanthones are one of the biggest classes of compounds in natural product chemistry. A number of xanthones have been isolated from natural sources of higher plants, fungi, ferns, and lichens. They have gradually risen to great importance because of their medicinal properties. This review focuses on the types, isolation, characterization, biological applications, and biosynthesis of naturally occurring xanthones isolated so far. Different physicochemical and instrumental methods such as liquid-solid and liquid-liquid extraction, TLC, flash chromatography, column chromatography, IR,1H NMR and13C NMR spectroscopy, GLC, HPLC, GC, and LCMS have been widely used for isolation and structural elucidation of xanthones. Hepatoprotective, anticarcinogenic, antileprosy, antimalarial, antioxidant, anticholinergic, mutagenicity, radioprotective, immunomodulatory, antibone resorption, antiparasitic, neuraminidase inhibitory, anticomplement, antibacterial, antifungal, algicidal, anti-HIV, cardioprotective, antitumoral, antidiabetes, antihyperlipidemic, antiatherogenic, anti-inflammatory, antiulcer, antidiabetic, hypolipidemic, analgesic, antiasthmatic, antihistaminic, antiamoebic, diuretic, antidiarrheal, larvicidal, and ovicidal activities have been reported for natural occurring xanthones. To a certain extent, this review provides necessary foundation for further research and development of new medicines.

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“…The genus Calophyllum is composed of about 130 species confined to the warm humid tropics of the world. Leaf decoction is traditionally used as an eye remedy in Asian medicine (Peres & Nagem, 1997). Different parts of the tree are a source of secondary metabolites such as triterpenes, steroids, benzopyrans, xanthones, coumarins, and neoflavonoids with biological properties (Laure et al, 2008).…”

Section: Introductionmentioning

confidence: 99%

Bioactive potential of endophyticMyrotheciumsp. isolate M1-CA-102, associated withCalophyllum apetalum

Karmakar

Sunil

Prakash

2014

Pharmaceutical Biology

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Context: Endophytes colonizing medicinal plants are diverse, constituting a rich bioresource for novel natural products. Objective: Myrothecium sp. isolate M1-CA-102 was the most promising among the 16 Myrothecium isolates screened. The bioactive potential of the crude extract from the Calophyllum apetalum Willd. endophytic Myrothecium sp. (Alb. & Schwein.) Ditmar (Incertae sedis) isolate M1-CA-102 and its thin layer chromatography (TLC) fractions were screened based on antioxidant, anti-inflammatory, antimicrobial activities, and cytotoxicity. Materials and methods: The antioxidant activity was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2 0 -azinobis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging capacities. Further, 15-lipoxygenase (15-LOX) and human cyclooxygenase-2 (COX-2) inhibition were assessed at different concentrations (25, 50, and 100 mg/mL for the crude extract, 5, 25, and 50 mg/mL for the TLC fractions). DNA-nicking assay as an indicator of the capacity of extracts to scavenge hydroxyl radical was recorded at a concentration of 50 mg/mL. Cell cytotoxicity was recorded by colorimetric 3-(4,5-dimethylthylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Antibacterial (Bacillus subtilis) and antiCandida (Candida albicans) assays were performed by the microdilution method. Results: The DPPH and ABTS IC 50 values of M1-CA-102 extract were 10 and 6 mg/mL compared with 6.1 and 7.03 mg/mL for the positive control quercetin. The cytotoxicity IC 50 value of M1-CA-102 extract was 37 mg/mL, while the M-I TLC fraction was 21 mg/mL. The M1-CA-102 extract gave an IC 50 value of 58 and 8 mg/mL for 15-LOX and COX-2, respectively. The MIC values for antimicrobial activity for M1-CA-102 extract ranged from 35 to 54 mg/mL, while for the TLC fractions, it ranged from 91 to 515 mg/mL. Conclusion:The results indicate that Myrothecium M1-CA-102 isolated from C. apetalum is a potential source of natural metabolites of pharmaceutical importance.

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Naturally occurring pentaoxygenated, hexaoxygenated and dimeric xanthones: a literature survey

Cited by 27 publications

References 69 publications

Xanthones and Oxepino[2, 3‐b]chromones from Three Endophytic Fungi

Xanthones and Oxepino[2, 3‐b]chromones from Three Endophytic Fungi

Naturally Occurring Xanthones: Chemistry and Biology

Bioactive potential of endophyticMyrotheciumsp. isolate M1-CA-102, associated withCalophyllum apetalum

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