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https://www.readbyqxmd.com/read/28107178/influence-of-structure-of-lactones-with-the-methylcyclohexene-and-dimethylcyclohexene-ring-on-their-biotransformation-and-antimicrobial-activity
#1
Katarzyna Wińska, Małgorzata Grabarczyk, Wanda Mączka, Barbara Żarowska, Gabriela Maciejewska, Mirosław Anioł
The aim of this article is influence of the structure of lactones with the methylcyclohexene and dimethylcyclohexene ring on their biotransformation and antimicrobial activity. This work was based on the general remark that even the smallest change in the structure of a compound can affect its biological properties. The results of the biotransformation of four bicyclic unsaturated lactones with one or two methyl groups in the cyclohexene ring was tested using fifteen fungal strains (Fusarium species, Penicillium species, Absidia species, Cunninghamella japonica, and Pleurotus ostreatus) and five yeast strains (Yarrowia lipolytica, Rhodorula marina, Rhodorula rubra, Candida viswanathii, and Saccharomyces cerevisiae)...
January 20, 2017: Zeitschrift Für Naturforschung. C, A Journal of Biosciences
https://www.readbyqxmd.com/read/28106760/asymmetric-total-synthesis-of-ieodomycin-b
#2
Shuangjie Lin, Jianting Zhang, Zhibin Zhang, Tianxiang Xu, Shuangping Huang, Xiaoji Wang
Ieodomycin B, which shows in vitro antimicrobial activity, was isolated from a marine Bacillus species. A novel asymmetric total synthetic approach to ieodomycin B using commercially available geraniol was achieved. The approach involves the generation of 1,3-trans-dihydroxyl at C-3 and C-5 positions via a Crimmins-modified Evans aldol reaction and a chelation-controlled Mukaiyama aldol reaction of a p-methoxybenzyl-protected aldehyde, as well as the generation of a lactone ring in a deprotection-lactonization one-pot reaction...
January 18, 2017: Marine Drugs
https://www.readbyqxmd.com/read/28106750/synthesis-and-biotransformation-of-bicyclic-unsaturated-lactones-with-three-or-four-methyl-groups
#3
Katarzyna Wińska, Małgorzata Grabarczyk, Wanda Mączka, Adrianna Kondas, Gabriela Maciejewska, Radosław Bonikowski, Mirosław Anioł
The aim of this study was to obtain new unsaturated lactones by chemical synthesis and their microbial transformations using fungal strains. Some of these strains were able to transform unsaturated lactones into different hydroxy or epoxy derivatives. Strains of Syncephalastrum racemosum and Absidia cylindrospora gave products with a hydroxy group introduced into a tertiary carbon, while the Penicillium vermiculatum strain hydroxylated primary carbons. The Syncephalastrum racemosum strain hydroxylated both substrates in an allylic position...
January 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28106218/expeditious-assembly-of-fused-dihydropyranones-via-n-heterocyclic-carbene-catalyzed-tandem-michael-addition-lactonization
#4
Qiao Ren, Muyao Li, Lujiang Yuan
A convergent and efficient NHC-catalyzed enantioselective tandem Michael addition/lactonization sequence of ynals with 1,2-dione as the dual-nucleophile is disclosed. This straightforward strategy expeditiously assembles the synthetically and pharmaceutically valuable optically active fused dihydropyranones in good to high yields (70-88%) and with excellent enantioselectivities (92-99% ee).
January 20, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28106208/studies-on-cyclization-reactions-of-3-amino-2-4-dihydroxybutanoic-acid-derivatives
#5
Mathieu Esgulian, Vincent Belot, Régis Guillot, Sandrine Deloisy, David J Aitken
A number of cyclic derivatives of 3-amino-2,4-dihydroxybutanoic acid are known in the literature but they are often prepared from other cyclic precursors. This study showed that the title compound too may serve as a convenient substrate for cyclization reactions. Using orthogonally-protected linear derivatives, regioselective cyclizations were performed, leading to original and highly-functionalized γ-lactones, oxazolidinones, oxazolines and aziridines. In these reactions a key role was played by the C3 nitrogen group function, while the C2 alcohol function showed no propensity for participation in cyclization reactions...
January 20, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28105814/radical-approach-to-the-chiral-quaternary-center-in-asperaculin-a-synthesis-of-9-deoxyasperaculin-a
#6
Dipendu Das, Tushar Kanti Chakraborty
Diastereoselective approaches toward the synthesis of a marine-derived sesquiterpenoid fungal metabolite, asperaculin A, are delineated, combining step economy and simplicity. Two distinct lactonization sequences from a common intermediate led to the first synthesis of 9-deoxyasperaculin A, a novel dioxa[5.5.5.6]fenestrane, in 14 steps (16% overall yield) and 16 steps (18% overall yield), respectively. [2,3]-Wittig-Still rearrangement and Ti(III)-mediated epoxide opening-cyclization were employed as some of the key steps for the stereoselective generation of the vicinal all-carbon quaternary centers of the target molecule...
January 20, 2017: Organic Letters
https://www.readbyqxmd.com/read/28105513/pharmacokinetics-of-ginkgolides-a-b-and-k-after-single-and-multiple-intravenous-infusions-and-their-interactions-with-midazolam-in-healthy-chinese-male-subjects
#7
Feng Shao, Hongwen Zhang, Lijun Xie, Juan Chen, Sufeng Zhou, Jinsong Zhang, Jinru Lv, Weiwen Hao, Yunsu Ma, Yun Liu, Ning Ou, Wei Xiao
PURPOSE: Ginkgo terpene lactones meglumine injection (GMI) is a novel preparation of traditional Chinese medicine that contains ginkgolides A, B and K (GA, GB, GK, respectively) as its primary components. In this study we evaluated the safety, tolerability and pharmacokinetics of these three ginkgolides after single and multiple intravenous infusions of GMI. We also investigated the effect of GMI on cytochrome P450 3A4 (CYP3A4) in healthy Chinese volunteers. METHODS: In this open-label, placebo-controlled study 15 subjects were randomly assigned to receive GMI or matched placebo (4:1 ratio)...
January 20, 2017: European Journal of Clinical Pharmacology
https://www.readbyqxmd.com/read/28104435/inhibition-of-nrf2-enhances-the-anticancer-effect-of-6-o-angeloylenolin-in-lung-adenocarcinoma
#8
Yang Wang, Ru-Yuan Yu, Jing Zhang, Wei-Xia Zhang, Zhi-Hao Huang, Hui-Fang Hu, Yao-Lan Li, Bin Li, Qing-Yu He
6-O-Angeloylenolin (6-OA), a sesquiterpene lactone isolated from Centipeda minima (L.) A. Br. (Compositae), has been used to treat respiratory diseases for centuries. However, whether and how 6-OA exerts anticancer effects against lung cancer remains to be elucidated. In this study, we showed that 6-OA markedly suppressed the cell viability and colony formation of lung cancer cells H1299 and A549, with no significant toxic effect on non-cancer cells HBE. Annexin V/7-AAD assay revealed that 6-OA induced cell apoptosis in dose- and time-dependent manners, which was further confirmed by the increased expression of cleaved caspase-3...
January 16, 2017: Biochemical Pharmacology
https://www.readbyqxmd.com/read/28103680/targeting-nf-%C3%AE%C2%BAb-p65-with-a-helenalin-inspired-bis-electrophile
#9
John C Widen, Aaron M Kempema, Peter W Villalta, Daniel A Harki
The canonical NF-κB signaling pathway is a mediator of the cellular inflammatory response and a target for developing therapeutics for multiple human diseases. The furthest downstream proteins in the pathway, the p50/p65 transcription factor heterodimer, have been recalcitrant toward small molecule inhibition despite the substantial number of compounds known to inhibit upstream proteins in the activation pathway. Given the roles of many of these upstream proteins in multiple biochemical pathways, targeting the p50/p65 heterodimer offers an opportunity for enhanced on-target specificity...
January 20, 2017: ACS Chemical Biology
https://www.readbyqxmd.com/read/28102373/unprecedented-photochemical-rearrangement-of-an-open-cage-c60-derivative
#10
Tsukasa Futagoishi, Michihisa Murata, Atsushi Wakamiya, Yasujiro Murata
Upon irradiation of a sulfoxide C60 derivative with a 17-membered-ring opening, rearrangement of the carbon framework took place to give an unprecedented lactone C60 derivative with a 14-membered-ring opening, whose structure was unambiguously determined by single crystal X-ray analysis. This reaction is completely different from that of the previously reported sulfoxide C60 and C70 derivatives with a 13-membered-ring opening.
January 19, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28099876/antitumoral-activity-of-sesquiterpene-lactone-diacethylpiptocarphol-in-mice
#11
Fronza Alezandre, Sabel Ricardo, Carrenho Luise Zozula Blind, Pollo Luis, Bratti Letícia de Oliveira Souza, Monteiro Fabíola Branco Filippin, Biavatti Maique Weber, Kreuger Maria Regina Orofino
ETHNOPHARMACOLOGICAL RELEVANCE: Sesquiterpene lactones are organic compounds derived from plants that exhibit anti-inflammatory and antitumor activities being one of the locking mechanisms of action of NF-kB pathway and synthesis of cytokines such as IL-1 and TNF- α. AIM OF THE STUDY: The overall objective of the present study was to evaluate the antitumor activity of the sesquiterpene lactone diacethylpiptocarphol (DPC) from Vernonia scorpioides (Lam.) Pers. in animal models Ehrlich tumors that has shown antitumor activity...
January 15, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28098763/new-abietane-and-kaurane-type-diterpenoids-from-the-stems-of-tripterygium-regelii
#12
Dongsheng Fan, Shuangyan Zhou, Zhiyuan Zheng, Guo-Yuan Zhu, Xiaojun Yao, Ming-Rong Yang, Zhi-Hong Jiang, Li-Ping Bai
Eleven new abietane type (1‒11), and one new kaurane (12), diterpenes, together with eleven known compounds (13-23), were isolated and identified from the stems of Tripterygium regelii, which has been used as a traditional folk Chinese medicine for the treatment of rheumatoid arthritis in China. The structures of new compounds were characterized by means of the interpretation of high-resolution electrospray ionization mass spectrometry (HRESIMS), extensive nuclear magnetic resonance (NMR) spectroscopic data and comparisons of their experimental CD spectra with calculated electronic circular dichroism (ECD) spectra...
January 13, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28098345/effect-of-sequential-fermentations-and-grape-cultivars-on-volatile-compounds-and-sensory-profiles-of-danish-wines
#13
Jing Liu, Nils Arneborg, Torben B Toldam-Andersen, Mikael A Petersen, Wender L P Bredie
BACKGROUND: There has been increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. In this work, three non-Saccharomyces yeast strains (Metschnikowia viticola, Metschnikowia fructicola and Hanseniaspora uvarum) indigenously isolated in Denmark, were used in sequential fermentations with S. cerevisiae on three cool-climate grape cultivars Bolero, Rondo and Regent. During the fermentations, the yeast growth was determined as well as key oenological parameters, volatile compounds and sensory properties of finished rosé wines...
January 18, 2017: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/28097636/andrographolide-antibacterial-activity-against-common-bacteria-of-human-health-concern-and-possible-mechanism-of-action
#14
Malabika Banerjee, Debaprasad Parai, Subrata Chattopadhyay, Samir Kumar Mukherjee
Increasing bacterial resistance to common drugs is a major public health concern for the treatment of infectious diseases. Certain naturally occurring compounds of plant sources have long been reported to possess potential antimicrobial activity. This study was aimed to investigate the antibacterial activity and possible mechanism of action of andrographolide (Andro), a diterpenoid lactone from a traditional medicinal herb Andrographis paniculata. Extent of antibacterial action was assessed by minimal bactericidal concentration method...
January 17, 2017: Folia Microbiologica
https://www.readbyqxmd.com/read/28095587/quantitative-determination-of-lactones-in-piper-methysticum-kava-kava-by-supercritical-fluid-chromatography
#15
Adele Murauer, Markus Ganzera
A fast and validated supercritical fluid chromatography method for the quantitative determination of major lactones in Piper methysticum, a plant used against nervous anxiety, stress, and restlessness, was developed. The baseline separation of dihydrokavain, demethoxyyangonin, kavain, yangonin, dihydromethysticin, and methysticin was possible in less than 4 min on an Aquity UPC(2) BEH 1.7 µm column, in combination with a mobile phase comprising CO2 and methanol with diethylamine. The column temperature had a great impact on the results because only at 70 °C could kavain and yangonin be fully resolved...
January 17, 2017: Planta Medica
https://www.readbyqxmd.com/read/28094185/anticomplement-triterpenoids-from-the-roots-of-ilex-asprella
#16
Quan Wen, Yan Lu, Zhi Chao, Dao-Feng Chen
Five new (1-5) and twenty-eight known (6-33) triterpenoids were isolated from the roots of Ilex asprella. The structures of the new compounds were elucidated by the detailed spectral analysis. The ursane and oleanane triterpenoids were found to show anticomplement activity with some structure-activity relationships. Several triterpenoids (1-3, 6-7) exhibited potent anticomplement activity with the CH50 and AP50 values of 0.058-0.131mg/mL and 0.080-0.444mg/mL, respectively. It was found that caffeoyl group could enhance activity remarkably, followed by coumaroyl and feruloyl group...
January 6, 2017: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28093888/synthesis-of-butyl-levulinate-based-on-%C3%AE-angelica-lactone-in-the-presence-of-easily-separable-heteropoly-acid-catalysts
#17
Xiaohu Yi, Ghith Al Shaal Mohammad, Ciptonugroho Wirawan, Irina Delidovich, Xiaohong Wang, Regina Palkovits
A series of choline exchanged heteropoly acids (HOCH2CH2N(CH3)3)XH(6-X)P2W18O62 [abbreviated as ChxH(6-X)P2W18O62 (x=1-6), Choline cation abbreviated as Ch+] was synthesized and used as catalysts for the reaction of α-angelica lactone (abbreviated as alpha-AL) with n-butanol forming butyl levulinate. The solubility of ChxH(6-X)P2W18O62 in the reaction mixture is temperature-dependent: The catalysts are soluble under the reaction conditions and precipitate upon cooling the reaction mixture. This facilitates recovery of the catalysts out of the liquid phase...
January 17, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28092216/metabolism-of-metofluthrin-in-rats-i-identification-of-metabolites
#18
Jun Abe, Hirohisa Nagahori, Hirokazu Tarui, Yoshitaka Tomigahara, Naohiko Isobe
Metofluthrin (2,3,5,6-tetrafluoro-4-(methoxymethyl)benzyl (Z/E)-(1R)-trans-2,2-dimethyl-3-(1-propenyl)-cyclopropanecarboxylate) is a novel pyrethroid insecticide, which has E/Z isomers at prop-1-enyl group. Rats were orally dosed with each [(14)C]-labeled E/Z isomer, and the excreta were collected for isolation and identification of metabolites. Analysis of the excreta by LC/MS and NMR revealed formation of 33 and 23 (total 42) metabolites from rats dosed with Z-isomer and E-isomer, respectively. Major metabolic reactions were cleavage of ester linkage, O-demethylation, hydroxylation, epoxidation or reduction of double bond, glutathione conjugation and its further metabolism, hydroxylation of epoxide, and formation of lactone ring...
January 16, 2017: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/28091709/use-of-in-silico-models-for-prioritization-of-heat-induced-food-contaminants-in-mutagenicity-and-carcinogenicity-testing
#19
Falko Frenzel, Thorsten Buhrke, Irina Wenzel, Jennifer Andrack, Jan Hielscher, Alfonso Lampen
Numerous Maillard reaction and lipid oxidation products are present in processed foods such as heated cereals, roasted meat, refined oils, coffee, and juices. Due to the lack of experimental toxicological data, risk assessment is hardly possible for most of these compounds. In the present study, an in silico approach was employed for the prediction of the toxicological endpoints mutagenicity and carcinogenicity on the basis of the structure of the respective compound, to examine (quantitative) structure-activity relationships for more than 800 compounds...
January 16, 2017: Archives of Toxicology
https://www.readbyqxmd.com/read/28089739/the-influence-of-seasonality-on-the-content-of-goyazensolide-and-on-anti-inflammatory-and-anti-hyperuricemic-effects-of-the-ethanolic-extract-of-lychnophora-passerina-brazilian-arnica
#20
Bruno César de Albuquerque Ugoline, Jacqueline de Souza, Fernanda Cristina Ferrari, Zilma Schimith Ferraz Filha, Grazielle Brandão Coelho, Dênia Antunes Saúde-Guimarães
ETHNOPHARMACOLOGICAL RELEVANCE: Lychnophora passerina (Mart ex DC) Gardn (Asteraceae), popularly known as Brazilian arnica, is used in Brazilian folk medicine to treat pain, rheumatism, bruises, inflammatory diseases and insect bites. AIM OF THE STUDY: Investigate the influence of the seasons on the anti-inflammatory and anti-hyperuricemic activities of ethanolic extract of L. passerina and the ratio of the goyazensolide content, main chemical constituent of the ethanolic extract, with these activities...
January 12, 2017: Journal of Ethnopharmacology
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