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Caroline Rouger, Sylvain Pagie, Séverine Derbré, Anne-Marie Le Ray, Pascal Richomme, Béatrice Charreau
Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i...
2016: PloS One
Yang Hee Jo, Seon Beom Kim, Qing Liu, Bang Yeon Hwang, Mi Kyeong Lee
Investigation of the CH2 Cl2 and EtOAc-soluble fractions of the roots of Cudrania tricuspidata afforded 31 compounds. The structures of the isolated compounds were determined on the basis of spectroscopic data interpretation such as 1D and 2D NMR analysis and elucidated as xanthones with prenyl moieties including four simple xanthones (1-4), five prenylated xanthones with one prenyl moiety (5-7, 20, and 21), and 22 prenylated xanthones with two prenyl moieties (8-19 and 22-31). Among them, three diprenylated xanthones named cudracuspixanthones E-G (16, 29, and 31) were first isolated in nature...
November 30, 2016: Archiv der Pharmazie
Tandeka U Magcwebeba, Pieter Swart, Sonja Swanevelder, Elizabeth Joubert, Wentzel C A Gelderblom
The chemopreventive properties of the herbal teas rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.) have been demonstrated on mouse skin in vivo but the underlying mechanisms are not clear. The aim of the current study was to determine the anti-proliferative and pro-apoptotic activity of methanol and aqueous extracts of rooibos and two Cyclopia species in different skin cells, using green tea (Camellia sinensis) as a benchmark. Extracts were also characterised for their major individual polyphenols by high performance liquid chromatography and spectroscopically for the total polyphenol (TP) groups...
November 25, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Hongju Liu, Senhua Chen, Weiyang Liu, Yayue Liu, Xishan Huang, Zhigang She
Nine polyketides, including two new benzophenone derivatives, peniphenone (1) and methyl peniphenone (2), along with seven known xanthones (3-9) were obtained from mangrove endophytic fungus Penicillium sp. ZJ-SY₂ isolated from the leaves of Sonneratia apetala. Their structures were elucidated on the basis of MS, 1D, and 2D NMR data. Compounds 1, 3, 5, and 7 showed potent immunosuppressive activity with IC50 values ranging from 5.9 to 9.3 μg/mL.
November 25, 2016: Marine Drugs
Karin Hientz, André Mohr, Dipita Bhakta-Guha, Thomas Efferth
Cancer has long been a grievous disease complicated by innumerable players aggravating its cure. Many clinical studies demonstrated the prognostic relevance of the tumor suppressor protein p53 for many human tumor types. Overexpression of mutated p53 with reduced or abolished function is often connected to resistance to standard medications, including cisplatin, alkylating agents (temozolomide), anthracyclines, (doxorubicin), antimetabolites (gemcitabine), antiestrogenes (tamoxifen) and EGFR-inhibitors (cetuximab)...
November 19, 2016: Oncotarget
Shinichiro Fuse, Keisuke Matsumura, Kohei Johmoto, Hidehiro Uekusa, Hiroshi Tanaka, Tomoyasu Hirose, Toshiaki Sunazuka, Satoshi Ōmura, Takashi Takahashi
A readily accessible template of 1,5,7-trisubstituted-3-pyridyl-xanthones was designed starting from naturally occurring pyripyropene A for agrichemical development. Our originally developed Ag2 CO3 -mediated oxidative cyclization enabled ready access to the key scaffold, 1,5,7-trihydroxy-3-chloro-xanthone. The chemo- and regioselective sequential introduction of four substituents to the scaffold rapidly afforded the desired, structurally diverse 1,5,7-trisubstituted-3-pyridyl-xanthones. An evaluation of insecticidal activity revealed that one of the synthesized compounds retained insecticidal activity against vetch aphid and green peach aphid...
November 9, 2016: Chemistry: a European Journal
Michal Markiewicz, Tadeusz Librowski, Anna Lipkowska, Pawel Serda, Krzysztof Baczynski, Marta Pasenkiewicz-Gierula
Xanthones are tricyclic compounds of natural or synthetic origin exhibiting a broad spectrum of therapeutic activities. Three synthetic xanthone derivatives (KS1, KS2, and KS3) with properties typical for nonsteroidal anti-inflammatory drugs (NSAID) were objects of the presented model study. NSAIDs are in common use however; several of them exhibit gastric toxicity predominantly resulting from their direct interactions with the outermost lipid layer of the gastric mucosa that impair its hydrophobic barrier property...
January 2017: Biophysical Chemistry
Kuo-Jun Zhang, Qin-Lan Gu, Kan Yang, Xian-Jun Ming, Jin-Xin Wang
Cancer chemoprevention is a promising strategy taken to block, reverse, or retard carcinogenesis. α-Mangostin, a natural xanthone isolated from the pericarps of mangosteen, represents one of the most studied chemopreventive agents. This compound has been reported to interfere with all the major stages of carcinogenesis: initiation, promotion, and progression. A number of mechanisms have been proposed for its anticarcinogenic activities. This review summarizes the current knowledge on the mechanisms that contribute to the observed activity of α-mangostin related to (i) modulation of carcinogenic biotransformation and mitigation of oxidative damage, (ii) induction of growth arrest and apoptosis, (iii) suppression of angiogenesis and metastasis, and (iv) combination with clinical chemotherapy drugs enhancing their efficacy and decreasing the toxic side effects...
November 4, 2016: Planta Medica
Bang Dong, Yun-Feng Zheng, Hong-Mei Wen, Xin-Zhi Wang, Hai-Wei Xiong, Hao Wu, Wei Li
Two new xanthones, gambogollic acid (1), epigambogollic acid (2), together with three rare compounds, gambogellic acid (3), epigambogellic acid (4) and gambogic acid (5), were isolated from the processed gamboge. The new structures were determined by 1D and 2D NMR spectroscopic analysis. And the cytotoxicity of these five compounds was evaluated against human hepatoma carcinoma and human lung adenocarcinoma cell. Two new compounds showed excellent antitumor activity. All five compounds exhibited inhibitory effect against SMMC-7221cell and A549 cell...
November 4, 2016: Natural Product Research
Hangjun Ke, Joanne M Morrisey, Shiwei Qu, Oraphin Chantarasriwong, Michael W Mather, Emmanuel A Theodorakis, Akhil B Vaidya
Caged Garcinia xanthones (CGXs) constitute a family of natural products that are produced by tropical/sub-tropical trees of the genus Garcinia CGXs have a unique chemical architecture, defined by the presence of a caged scaffold at the C ring of a xanthone moiety and exhibit a broad range of biological activities. Here we show that synthetic CGXs exhibit antimalarial activity against Plasmodium falciparum, the causative parasite of human malaria, at the intra-erythrocytic stages. The activity can be substantially improved by attaching a triphenylphosphonium group at the A ring of the caged xanthone...
October 31, 2016: Antimicrobial Agents and Chemotherapy
Cholpisut Tantapakul, Wisanu Maneerat, Tawanun Sripisut, Thunwadee Ritthiwigrom, Raymond J Andersen, Ping Cheng, Sarot Cheenpracha, Achara Raksat, Surat Laphookhieo
Two new benzophenones (1 and 2) and four new xanthones (4-6 and 17) together with 24 known compounds (3, 7-16 and 18-30) were isolated from the roots and twigs of Cratoxylum sumatranum ssp. neriifolium. Their structures were elucidated by spectroscopic methods. Compounds 5 and 26 showed antibacterial activity against Micrococcus luteus, Bacillus cereus, and Staphylococcus epidermis with MIC values ranging from 4-8 µg/mL, whereas compounds 7, 20, and 26 displayed selective antibacterial activities against Staph...
October 27, 2016: Journal of Agricultural and Food Chemistry
Teddy Stephen Ehianeta, Stéphane Laval, Biao Yu
Mangiferin (2C-β-d-glucopyranosyl-1,3,6,7-tetrahydroxyxanthone) is a xanthone C-glycoside occurring in many plant species. Composed of a glucose unit C1→2 linked to a 1,3,6,7-tetrahydroxyxanthone aglycone, mangiferin exhibits a wide range of biological activities, which recently renewed its interest as a potential pharmacophore. Mangiferin is mainly isolated after extraction procedures from natural sources alongside with its isoforms isomangiferin, homomangiferin, and neomangiferin. However, enzymatic and chemical approaches have been developed to access these phytochemicals, which address the challenging construction of the C-glycosidic linkage...
September 10, 2016: BioFactors
Xiaoli Xu, Yue Wu, Mingyang Hu, Xiang Li, Qichao Bao, Jinlei Bian, Qidong You, Xiaojin Zhang
DDO-6101, a simplified structure obtained from the Garcinia natural product (NP) gambogic acid (GA), has been previously shown to possess high cytotoxicity to a variety of human tumour cell lines. To improve its physicochemical properties and in vivo cytotoxic potency, a series of novel carbamate-bearing derivatives based on DDO-6101 was synthesized and characterized. The structural modifications revealed that the presence of a carbamate moiety was useful for obtaining comparable cytotoxicity and improved aqueous solubility and permeability...
October 21, 2016: Scientific Reports
Hong Zhang, Zheng Dan, Zhi-Jie Ding, Yuan-Zhi Lao, Hong-Sheng Tan, Hong-Xi Xu
A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1-2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V-Z (3-7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry...
October 21, 2016: Scientific Reports
Alamgir A Dar, Nisar A Dangroo, Arun Raina, Arem Qayum, Shashank Singh, Anil Kumar, Payare L Sangwan
Five new xanthones, named coxanthones A-E (1-5), together with 21 known secondary metabolites (6-26) that include seven xanthones, five flavonoids, two steroids and seven triterpenoids were isolated from the chemically unexplored whole plant Codonopsis ovata. The structures of new metabolites were elucidated by HRMS, interpretation of NMR spectra and other spectroscopic techniques. The absolute configuration of the stereogenic centre of coxanthone B (2) was determined by electronic circular dichroism (ECD) spectroscopy...
October 10, 2016: Phytochemistry
Hossam M Abdallah, Hany M El-Bassossy, Gamal A Mohamed, Ali M El-Halawany, Khalid Z Alshali, Zainy M Banjar
Advanced glycation end-products (AGEs) are associated with a non-enzymatic reaction between the amino group of a protein and the carbonyl group of a sugar during hyperglycemia. The precipitation of AGEs in different tissues leads to many complications, such as endothelial dysfunction, cardiovascular complications, atherosclerosis, retinopathy, neuropathy, and Alzheimer's disease. Garcinia mangostana L. (Clusiaceae) (GM) was selected owing to the ability of its polar and non-polar fractions to inhibit AGE formation...
October 13, 2016: Journal of Natural Medicines
M Cuccioloni, L Bonfili, M Mozzicafreddo, V Cecarini, S Scuri, M Cocchioni, M Nabissi, G Santoni, A M Eleuteri, M Angeletti
Mangiferin is a natural xanthone glycoside with therapeutic potential. Herein, its cytotoxic properties were explored in a human cell model of breast adenocarcinoma. The results supported the multi-target nature of mangiferin action, as the inhibition of three enzymatic systems, namely HMG-CoA reductase, the proteasome and plasmin, respectively in charge of regulating cholesterol homeostasis, protein turnover and cell adhesion, was documented for the first time. Globally, mangiferin was able to selectively block breast cancer cell growth by inducing apoptosis and by arresting cell proliferation through a combined action on cholesterol and proteasome pathways, as well as to inhibit plasmin-mediated mechanisms of cell migration...
October 12, 2016: Food & Function
Xiong Wei, Danlin Liang, Qing Wang, Xiangbao Meng, Zhongjun Li
Total synthesis of mangiferin, homomangiferin, and neomangiferin, three C-glycosyl xanthone natural products with a wide spectrum of pharmacological effects, has been achieved starting from 2,3,4,6-tetra-O-benzyl-α/β-d-glucopyranose. The key steps involve a stereoselective Lewis acid promoted C-glycosylation of protected phloroglucinol with tetrabenzylglucopyranosyl acetate and a highly regioselective base-induced cyclization for the construction of the core xanthone skeleton.
September 21, 2016: Organic & Biomolecular Chemistry
Tandeka Magcwebeba, Pieter Swart, Sonja Swanevelder, Elizabeth Joubert, Wentzel Gelderblom
Ultraviolet B (UVB) radiation is one of the major predisposing risk factors of skin cancer. The anticancer and photoprotective effects of unoxidized rooibos (Aspalathus linearis) and honeybush (Cyclopia) herbal teas, containing high levels of dihydrochalones and xanthones, respectively, have been demonstrated in skin cancer models in vivo. In the current study, the anti-inflammatory effects of methanol and aqueous extracts of these herbal teas were investigated in a UVB/HaCaT keratinocyte model with intracellular interleukin-1α (icIL-1α) accumulation as a biomarker...
October 2, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Yanhua Jia, Chengwen Xiong
The anti-microbial and anti-oxidant effects of xanthones extract from Swertia macrosperma C.B. Clark were investigated using extracts from whole plant and partitioned by petroleum ether, ethyl acetate and n-butanol, respectively. Anti-microbial and anti-oxidant activities were detected among different fractions. High-performance liquid chromatography was performed to separate and purify the elutions. The compounds were elucidated by 1H, 13C NMR and LCMS. The ethyl acetate extract showed maximum inhibitory activity in fungal organisms and Gram-positive bacteria, and had the highest anti-oxidant capacity...
August 10, 2016: Natural Product Research
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