Showing papers on "Xanthone published in 2020"
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TL;DR: It is indicated that xanthones can be served as promising candidates for lead compounds of agrochemicals and the presence of a double bond in the furan ring could decrease phytotoxicity.
Abstract: Fungi have been proved as promising and prolific sources of functional secondary metabolites with potent agricultural applications. In this study, 14 xanthone derivatives (1-14), including six new ones, versicones I-N (1-4, 7, 11), and a biogenetically related derivative (15), were isolated from the alga-derived fungus Aspergillus versicolor D5. Their structures were elucidated by comprehensive spectroscopic methods. Versicone L (4) exhibited a broad antifungal spectrum and prominent inhibitory effects on Botrytis cinerea at a minimum inhibitory concentration (MIC) of 152 μM, 7-fold stronger than that of the positive control, carbendazim (MIC = 1.05 × 103 μM). Dihydrosterigmatocystin (13) showed strong antifungal activity toward B. cinerea at MIC = 38.3 μM, almost 30-fold stronger than that of carbendazim. Meanwhile, 13 exhibited potent herbicidal activity toward Amaranthus retroflexus L. with an MIC of 24.5 μM, approximately 4-fold stronger than that of the positive control, glyphosate (MIC = 94.7 μM). Additionally, 13 also displayed remarkable activity against other weeds belonging to Amaranth sp. Analysis of the structure-herbicidal activity relationship indicated that the bifuranic ring played an important role in xanthone phytotoxicity and the presence of a double bond in the furan ring could decrease phytotoxicity. This study indicated that xanthones can be served as promising candidates for lead compounds of agrochemicals.
21 citations
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TL;DR: In this paper, a highly convergent approach was developed to achieve the first asymmetric and scalable total synthesis of FD-594, a complex polycyclic xanthone natural product from Streptomyces sp. TA-0256, in a longest linear sequence of 20 steps.
Abstract: A highly convergent approach was developed to achieve the first asymmetric and scalable total synthesis of FD-594, a complex polycyclic xanthone natural product from Streptomyces sp. TA-0256, in a longest linear sequence (LLS) of 20 steps. The trans-9,10-dihydrophenanthrene-9,10-diol fragment (B-C-D ring) was generated through a new strategy involving asymmetric dihydroxylation followed by Cu-mediated oxidative cyclization. Late-stage stereoselective glycosylation assembled the angular hexacyclic framework with a β-linked 2,6-dideoxy trisaccharide fragment.
20 citations
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TL;DR: The mangrove-derived endophytic fungus Peniophora incarnata Z4 produced seven new xanthone derivatives, including four new tetrahydroxanthones (1-4), one new chromone (5), onenew xanth one (6), and one newxanthone dimer (7), together with one known compound, globosuxanthone B (8).
Abstract: The mangrove-derived endophytic fungus Peniophora incarnata Z4 produced seven new xanthone derivatives, including four new tetrahydroxanthones (1-4), one new chromone (5), one new xanthone (6), and one new xanthone dimer (7), together with one known compound, globosuxanthone B (8). Their structures were determined by an extensive analysis of 1D and 2D NMR, HRESIMS, ECD, and single-crystal X-ray diffraction data. In cytotoxic activity assays, compound 2 showed cytotoxicity against three carcinoma cell lines with IC50 values less than 10 μM.
19 citations
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TL;DR: Ten previously undescribed compounds, including five prenylated xanthones, two caged xanthone bearing a rare 8, 8a-epoxy moiety and three rearranged benzophenones, together with nineteen known compounds were isolated from the fruits of Garcinia bracteata to enrich the structural diversities ofxanthones and Benzophenones from Garcinia plants.
14 citations
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TL;DR: Investigation of the regulatory effects of xanthone in ACD in human keratinocytes (HaCaT cell), and human mast cell line (HMC-1 cell) in vitro and in an experimental murine model suggests that it has a potential for use in the treatment of allergic inflammatory diseases.
14 citations
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TL;DR: A new stereoisomeric pyrano xanthone together with the previously known fungal metabolites, epiisoshamixanthone, was obtained from the endophytic fungal strain Aspergillus sp.
14 citations
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TL;DR: Results suggested that 1‐hydroxy‐3‐[2‐(pyrrolidin‐1‐yl)ethoxy]‐9H‐xanthen‐9‐one was promising AChEI with metal chelating ability and antioxidant ability for the further investigation.
Abstract: Four xanthone derivatives were synthesized and evaluated as acetylcholinesterase inhibitors (AChEIs) with metal chelating ability and antioxidant ability against Alzheimer's disease (AD). Most of them exhibited potential acetylcholinesterase (AChE), butylcholinesterase (BuChE) inhibitory, antioxidant and metal chelating properties. Among them, 1-hydroxy-3-[2-(pyrrolidin-1-yl)ethoxy]-9H-xanthen-9-one had the highest ability to inhibit AChE and displayed high selectivity towards AChE (IC50 =2.403±0.002 μM for AChE and IC50 =31.221±0.002 μM for BuChE), and it was also a good antioxidant (IC50 =2.662±0.003 μM). Enzyme kinetic studies showed that this compound was a mixed-type inhibitor, which could interact simultaneously with the catalytic anionic site (CAS) and the peripheral anionic site (PAS) of AChE. Interestingly, its copper complex showed more significant inhibitory activity for AChE (IC50 =0.934±0.002 μM) and antioxidant activity (IC50 =1.064±0.003 μM). Molecular dockings were carried out for the four xanthone derivatives in order to further investigate the binding modes. Finally, the blood-brain barrier (BBB) penetration prediction indicated that all compounds might penetrate BBB. These results suggested that 1-hydroxy-3-[2-(pyrrolidin-1-yl)ethoxy]-9H-xanthen-9-one was promising AChEI with metal chelating ability and antioxidant ability for the further investigation.
14 citations
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TL;DR: The findings present the anticonvulsant activity of oliganthin H, provide a novel scaffold for further modifications, and highlight the xanthone skeleton as an attractive and reliable resource for the development of emerging AEDs.
Abstract: Epilepsy is a chronic neurological disorder, characterized by recurrent, spontaneous, and transient seizures, and affects more than 70 million people worldwide. Although two dozen antiepileptic drugs (AEDs) are approved and available in the market, seizures remain poorly controlled in one-third of epileptic patients who are suffering from drug resistance or various adverse effects. Recently, the xanthone skeleton has been regarded as an attractive scaffold for the discovery and development of emerging anticonvulsants. We had isolated several dihydroxanthone derivatives previously, including oliganthin H, oliganthin I, and oliganthin N, whose structures were similar and delicately elucidated by spectrum analysis or X-ray crystallographic data, from extracts of leaves of Garcinia oligantha. These xanthone analogues were evaluated for anticonvulsant activity, and a novel xanthone, oliganthin H, has been identified as a sound and effective natural inhibitor of convulsions in zebrafish in vivo. A preliminary structure-activity relationship analysis on the relationship between structures of the xanthone analogues and their activities was also conducted. Oliganthin H significantly suppressed convulsant behavior and reduced to about 25% and 50% of PTZ-induced activity, in 12.5 and 25 μM treatment groups (P < 0.01 and 0.001), respectively. Meanwhile, it reduced seizure activity, velocity, seizure duration, and number of bursts in zebrafish larvae (P < 0.05). Pretreatment of oliganthin H significantly restored aberrant induction of gene expressions including npas4a, c-fos, pyya, and bdnf, as well as gabra1, gad1, glsa, and glula, upon PTZ treatment. In addition, in silico analysis revealed the stability of the oliganthin H-GABAA receptor complex and their detailed binding pattern. Therefore, direct interactions with the GABAA receptor and involvement of downstream GABA-glutamate pathways were possible mechanisms of the anticonvulsant action of oliganthin H. Our findings present the anticonvulsant activity of oliganthin H, provide a novel scaffold for further modifications, and highlight the xanthone skeleton as an attractive and reliable resource for the development of emerging AEDs.
13 citations
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TL;DR: It is concluded that xanthone could be a dietary supplement for the patient with diabetic complications by exhibiting potent in vitro antioxidant and antidiabetic activity.
Abstract: Objective: Our previous studies reported that xanthone can protect from hyperglycemia-induced diabetes mellitus (DM) via possessing antioxidant activity. An attempt has been made to evaluate the pr...
11 citations
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11 citations
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TL;DR: The present study could provide new insight into the potential application of mangosteen as functional food ingredients for inhibiting the activity of QR-2, and the extent of daily intake of Mangosteen required and the exact contribution of mango to the prevention and treatment of malaria remain subjects of further study.
Abstract: Garcinia mangostana L. (mangosteen) is a famous tropical fruit that contains a large number of xanthones. Regular consumption of mangosteen may confer health benefits and prevent some diseases, such as malaria. Quinone reductase 2 (QR-2) is a cytosolic enzyme found in human red blood cells, and it is becoming a target for chemoprevention because it is involved in the mechanisms of several diseases, including malaria. To understand whether the xanthones present in mangosteen might inhibit the activity of QR-2, blood samples were collected from rat following the oral administration of mangosteen extract and then incubated with QR-2 followed by UF-HPLC-QTOF/MS analysis to rapidly screen for and identify the QR-2-inhibiting xanthones. A total of 16 xanthones were identified, and six of these (α-mangostin, γ-mangostin, 8-deoxyartanin, 1,3,7-trihydroxy-2,8-di(3-methylbut-2-enyl)xanthone, garcinone E, and 9-hydroxycalabaxanthone) were subjected to QR-2 inhibition assay. γ-Mangostin exhibited the strongest inhibition, achieving an IC50 value of 3.82 ± 0.51 μM. Its interaction with QR-2 was found to involve hydrogen bond and arene-arene interaction as revealed by molecular docking. The present study could provide new insight into the potential application of mangosteen as functional food ingredients for inhibiting the activity of QR-2. However, the extent of daily intake of mangosteen required and the exact contribution of mangosteen to the prevention and treatment of malaria remain subjects of further study.
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TL;DR: The antiparasitic activities against Plasmodium falciparum as well as the cytotoxic activity against seven cell lines were determined for the new compounds 1-3, and led from null to mild bioactivities.
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TL;DR: Nonmetric multidimensional scaling analysis revealed α-mangostin and γ-m Mangostin of pericarp as the key metabolites contributing to cholinesterase inhibition.
Abstract: Mangosteen is one of the best tasting tropical fruit widely cultivated in Southeast Asia This study aimed to quantify xanthone content in different parts of Garcinia mangostana by LC-QTOF-MS and d
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TL;DR: Based on the binding interaction showed, the sulfonamide substituted xanthone has potential being the anti-tuberculosis drugs by KasA inhibitor for target drug activity.
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TL;DR: The new tetraoxygenated xanthone was tested against a panel of eight bacterial strains including six Gram-negative and two Gram-positive bacteria and exhibited weak antibacterial activity with MIC values ranging from 64 to 128 µg/mL.
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TL;DR: The extract of the strain Aspergillus flavipes DL‐11 exerted antibacterial activities against six Gram‐positive bacteria and showed moderate to strong antibacterial effects on different Gram‐ positive bacteria, but none of the compounds exhibited activity against Gram‐negative bacteria Vibrio parahaemolyticus ATCC17802 (MIC>100 μg/mL).
Abstract: The extract of the strain Aspergillus flavipes DL-11 exerted antibacterial activities against six Gram-positive bacteria. During the following bioassay-guided separation, ten diphenyl ethers (1-10), two benzophenones (11-12), together with two xanthones (13-14) were isolated. Among them, 4'-chloroasterric acid (1) was a new chlorinated diphenyl ether. Their structures were elucidated by extensive spectroscopic data analysis, including IR, HR-ESI-MS, NMR experiments, and by comparison with the literature data. All compounds showed moderate to strong antibacterial effects on different Gram-positive bacteria with MIC values that ranged from 3.13 to 50 μg/mL, but none of the compounds exhibited activity against Gram-negative bacteria Vibrio parahaemolyticus ATCC17802 (MIC>100 μg/mL). In particular, the MICs of some compounds are at the level of positive control.
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TL;DR: Findings indicate that prenylated xanthones are potential new drug leads for antidiabetes therapy by stimulating β-cell regeneration in a zebrafish model.
Abstract: This project was focused on the discovery of novel compounds that promote endogenous β-cell regeneration. Screening of extracts identified the fungus Stachybotrys chartarum as a promising candidate. After fermentation and extraction of S. chartarum, we isolated five new prenylated xanthones, namely, staprexanthones A-E (1-5), with staprexanthone A (1) being the first natural xanthone bearing a rare 4,5-dimethyl-1,3-dioxolane moiety. Compounds 1, 2, and 5 significantly increased β-cell numbers in vivo in a zebrafish model. Further analysis revealed that 2 and 5 promoted β-cell mass expansion by increasing proliferation of existing β-cells though promotion of cell-cycle progression at the G1/S transition. These findings indicate that prenylated xanthones are potential new drug leads for antidiabetes therapy by stimulating β-cell regeneration.
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TL;DR: In this paper, two derivatives of xanthone (9H-xanthen-9-one, dibenzo-γ-pyrone) containing a maleimide moiety have been synthesized.
Abstract: Two novel derivatives of xanthone (9H-xanthen-9-one, dibenzo-γ-pyrone) containing a maleimide moiety have been synthesized. Their properties were characterized by the combination of NMR, MS, electronic absorption and fluorescence spectroscopy. The reactivity of these compounds toward l -Cys as well other analytes was determined. The results show that the novel derivatives of xanthone demonstrate a high “turn-on” fluorescence response and selectivity toward l -cysteine and have the potential to act as probes to l -cysteine under physiological conditions. Reaction of 2-maleimidoxanthone (4a) and 2,7-dimaleimidoxanthone (4b) with l -Cys lead to the formation of the fluorescent products. In the presence of L-Cys, the fluorescence intensities of probes 4a and 4b have greatly enhanced 25-fold and 60-fold, respectively. Finally, the probes 4a-4b were used to detection of thiols in the human cell line HeLa.
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TL;DR: A transcript for a plant acyl-activating enzyme (AAE) was cloned from xanthone-producing H. calycinum cell cultures and indicated that HcAAE1 exhibits promiscuous substrate preference, with benzoic acid being the sole aromatic substrate accepted.
Abstract: Benzoic acid-derived compounds, such as polyprenylated benzophenones and xanthones, attract the interest of scientists due to challenging chemical structures and diverse biological activities. The genus Hypericum is of high medicinal value, as exemplified by H. perforatum. It is rich in benzophenone and xanthone derivatives, the biosynthesis of which requires the catalytic activity of benzoate-coenzyme A (benzoate-CoA) ligase (BZL), which activates benzoic acid to benzoyl-CoA. Despite remarkable research so far done on benzoic acid biosynthesis in planta, all previous structural studies of BZL genes and proteins are exclusively related to benzoate-degrading microorganisms. Here, a transcript for a plant acyl-activating enzyme (AAE) was cloned from xanthone-producing Hypericum calycinum cell cultures using transcriptomic resources. An increase in the HcAAE1 transcript level preceded xanthone accumulation after elicitor treatment, as previously observed with other pathway-related genes. Subcellular localization of reporter fusions revealed the dual localization of HcAAE1 to cytosol and peroxisomes owing to a type 2 peroxisomal targeting signal. This result suggests the generation of benzoyl-CoA in Hypericum by the CoA-dependent non-β-oxidative route. A luciferase-based substrate specificity assay and the kinetic characterization indicated that HcAAE1 exhibits promiscuous substrate preference, with benzoic acid being the sole aromatic substrate accepted. Unlike 4-coumarate-CoA ligase and cinnamate-CoA ligase enzymes, HcAAE1 did not accept 4-coumaric and cinnamic acids, respectively. The substrate preference was corroborated by in silico modeling, which indicated valid docking of both benzoic acid and its adenosine monophosphate intermediate in the HcAAE1/BZL active site cavity.
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TL;DR: A novel 1,4-oxazine-xanthone derivative, fusarioxazin, possessed a significant antibacterial activity towards S. aureus and B. cereus and displayed a promising cytotoxic effect toward HCT-116, MCF-7, and A549.
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TL;DR: A new monomeric nidulalin D and four known analogues, together with a xanthone dimer bearing an unprecedented heptacyclic 6/6/six/6-6/6 /6/Six/6 system, were isolated from Aspergillus sp.
Abstract: Nidulaxanthone A (1), a xanthone dimer bearing an unprecedented heptacyclic 6/6/6/6/6/6/6 system, together with a new monomeric nidulalin D (2) and four known analogues (3, 4, 5 and 6), were isolated from Aspergillus sp. F029. Biosynthetically, 1 was likely generated via [4 + 2] cycloaddition of precursor 3. Compounds 1, 2, and 3 exhibited cytotoxicity with IC50 values ranging from 3.2 to 21.9 μM, and antibacterial activity with MIC50 values of 13.2 and 19.6 μg ml−1 for 2 and 3, respectively.
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TL;DR: In this article, a series of derivatives of α-mangostin, a polyphenol xanthone derivative of mangosteen fruit (Garcinia mangostana L).
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TL;DR: Experimental solubilities have been determined for xanthone dissolved in 15 different alcohol solvents (ethanol, 1propanol, 1-butanol and 1-hexanol) to within 0.096 log units.
Abstract: Experimental solubilities have been determined for xanthone dissolved in 15 different alcohol solvents (ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-ethyl-1-hexanol, 2-propanol, 2-butanol, 4-methyl-2-pentanol, 2-methyl-2-propanol and 2-methyl-2-butanol), in five alkyl acetate solvents (methyl acetate, ethyl acetate, propyl acetate, butyl acetate and pentyl acetate), in diisopropyl ether and in 2-ethoxyethanol at 298.2 K. In total, solubility measurements were performed in 22 organic solvents of varying polarity and hydrogen-bonding character. Results of the experimental measurements were used to calculate the Abraham model solute descriptors for xanthone. The calculated solute descriptors describe the experimental solubility data to within 0.096 log units.
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TL;DR: Mangiferin metabolites were identified and quantitated in the fermentation broths by high performance liquid chromatography–diode array detection–electrospray ionization-mass spectrometry, and structures confirmed unequivocally by nuclear magnetic resonance, after purification by semipreparative HPLC.
Abstract: Several natural drugs (termed prodrugs) when administered orally undergo transformation by intestinal bacteria, producing metabolites, which may be more active than the parent compound. Mangiferin ...
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03 Aug 2020TL;DR: The findings provided a rationale for the development of α-MG to attenuate cisplatin-induced nephrotoxicity, and significantly suppressed the overproduction of reactive oxygen species (ROS), restored the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), and downregulated the c-JUN N-terminal kinase (JNK) pathways following cisPlatin challenge.
Abstract: Previous report has confirmed the beneficial effects of α-mangostin (α-MG), a major and representative xanthone distributed in mangosteen (Garcinia mangostana) on the cisplatin-induced rat model. However, the molecular mechanisms related to its renoprotection have not been elucidated exhaustively. The present study investigated the protective effect of α-MG against cisplatin-induced cytotoxicity in the human embryonic kidney (HEK293) cell model. In this study, α-MG prevented cisplatin-induced cell death, accompanied with the decreased levels of malondialdehyde and increased glutathione content. Particularly, α-MG significantly suppressed the overproduction of reactive oxygen species (ROS), restored the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), and downregulated the c-JUN N-terminal kinase (JNK) pathways following cisplatin challenge. Subsequently, the cleavage of caspases and poly-ADP-ribose polymerase (PARP) implicating ROS-mediated apoptosis pathways induced by cisplatin was effectively inhibited by α-MG. In conclusion, our findings provided a rationale for the development of α-MG to attenuate cisplatin-induced nephrotoxicity.
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TL;DR: In this paper, the effect of different drying techniques (oven-, spray-, and freeze drying) on xanthone, a poorly aqueous-soluble bioactive compound, encapsulated by coacervation using a coacherer, was compared.
Abstract: This study aims to compare the effect of different drying techniques (oven-, spray-, and freeze drying) on xanthone, a poorly aqueous-soluble bioactive compound, encapsulated by coacervation using ...
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TL;DR: In this paper, an oil-in-water emulsion was developed for the encapsulation of xanthone, a potent anti-inflammatory and antitumor molecule of natural source.
Abstract: In the present work, an oil-in-water emulsion was developed for the encapsulation of xanthone, a potent anti-inflammatory and antitumor molecule of natural source. The xanthone is insoluble...