14919-49-4Relevant articles and documents
Microbial metabolism. Part 6. Metabolites of 3- and 7-hydroxyflavones
Herath, Wimal,Mikell, Julie Rakel,Hale, Amber Lynn,Ferreira, Daneel,Khan, Ikhlas Ahmad
, p. 320 - 324 (2006)
Fermentation of 3-hydroxyflavone (1) with Beauveria bassiana (ATCC 13144) yielded 3,4′-dihdroxyflavone (3), flavone 3-O-β-D-4-O- methylglucopyranoside (4) and two minor metabolites. 7-Hydroxyflavone (2) was transformed by Nocardia species (NRRL 5646) to 7-methoxyflavone (5) whilst Aspergillus alliaceus (ATCC 10060) converted it to 4′,7-dihydroxyflavone (6). Flavone 7-O-β-D-4-O-metylglucopyranoside (7) and 4′- hydroxyflavone 7-O-β-D-4-O-methylglucopyranoside (8) were the metabolic products of 7-hydroxyflavone (2) when fermented with Beauveria bassiana (ATCC 7159). One of the minor metabolites of 3-hydroxyflavone (1) was tentatively assigned a β′-chalcanol structure (9). Compounds 4, 7 and 8 are reported as new compounds. Structure elucidation of the metabolites was based on spectroscopic data.
Synthesis of Flavonols via Pyrrolidine Catalysis: Origins of the Selectivity for Flavonol versus Aurone
Xiong, Wei,Wang, Xiaohong,Shen, Xianyan,Hu, Cuifang,Wang, Xin,Wang, Fei,Zhang, Guolin,Wang, Chun
supporting information, p. 13160 - 13176 (2020/11/23)
A novel synthetic method for flavonol from 2′-hydroxyl acetophenone and benzaldehyde promoted by pyrrolidine under an aerobic condition in water is established. This protocol was supported by efficient synthesis of 44 common examples and three natural products. The α, β-unsaturated iminium ion (enimine ion E) was proved to be the key intermediate in the reaction. H218O and 18O2 isotope tracking experiments demonstrated that both water and the aerobic atmosphere were necessary to ensure the transformation. The selectivity for flavonol or aurone was originated from solvent-triggered intermediates, which were determined by UV-visible spectra from isolated enimine. The phenol-iminium E-A is dominant in water and the ketoenamine intermediate E-B is prevalent in acetonitrile. In the presence of pyrrolidine and oxygen, E-A leads to flavonol through E-I, a zwitterionic-like phenoloxyl-iminium ion, following the key steps of cyclization and a [2 + 2] oxidation; E-B proceeds through path II, a radical process induced by photolysis of E-B with both pyrrolidine and oxygen, to afford aurone. Preliminary mechanistic studies are reported.
Faster and More Specific: Excited-State Intramolecular Proton Transfer-Based Dyes for High-Fidelity Dynamic Imaging of Lipid Droplets within Cells and Tissues
Jiang, Gangwei,Jin, Yi,Li, Man,Liu, Changlin,Liu, Chunrong,Ren, Zhuqing,Wang, Huiling,Xiong, Mengyao,Yuan, Hong,Zeng, Weili
, p. 10342 - 10349 (2020/09/18)
Lipid droplets (LDs), a type of dynamic organelle residing at the center of cellular lipid storage, have been identified to play important roles in multiple biological processes, metabolic disorders, and diseases. The highly dynamic characters of LDs were found to correspond to their physiological and pathological functions. Hence, the fluorescent probes which enable dynamic tracking of LDs should be very helpful for better understanding the mechanisms of LDs involved biological processes and diseases. Herein we present, to the best of our knowledge, the first class of excited-state intramolecular proton transfer (ESIPT) fluorescence dyes (Flp-(11-13, 19)) for dynamic imaging of LDs based on 3-hydroxyflavone (3HF) derivatives. Flp-(11-13, 19) display strong fluorescence from yellow to NIR in lipid but exhibit almost nonfluorescence in aqueous solution. Besides, they also show large Stokes shifts (>150 nm), narrow absorption and emission peaks, and good oil-water separation efficiency, which makes them specifically target and stain LDs with very low background noisy in both living cells and fixed cells. They stain intracellular LDs quite quickly (within 30 s) with very low dosage (as low as 500 nM). Benefitting from these advantages, Flp-(11-13, 19) are applied successfully in tracking the dynamic nature of LDs and accumulation of LDs in both aqueous solution and living cells, 3D imaging of LDs for visualization of their repartition within the cells, and visualizing LDs in tissues of diseases mice models including adipose, skeletal muscle, and fatty liver tissues, underscoring the potential utility of these dyes in both LDs biology research and medical diagnosis of LDs involved diseases.
Phototransformations of some 3-cyclohexenyloxychromenones: Synthesis of Spirocyclic compounds
Khanna, Radhika,Dalal, Aarti,Berar, Urmila,Singh, Sandeep,Kamboj, Ramesh C.
, p. 668 - 673 (2019/01/05)
The phototransformation of the 3-cyclohexenyloxychromenones by irradiation with a pyrex-filtered light from a 125 W Hg vapor lamp under an inert atmosphere into the spirocyclic fused xanthenones was described. The efficacy of the protocol depended upon th
Synthesis, characterization and antimicrobial evaluation of cobalt(III) complexes of 4-(2-substituted phenylimino)-2-(4-substituted phenyl)-4H-chromen-3-ol
Singh, Ashok K.,Patel, Suresh K.,Jafri, Asif
, p. 2015 - 2021 (2019/08/08)
A series of eight Co(III) complexes [CoL1-8(H2O)2Cl] (I-1 to I-8) incorporating 4-(2-substituted phenylimino)-2-(4-substituted phenyl)-4H-chromen-3-ol, as a tridentate imino flavone ligands (L1 to L8, 2-sub. = NH2, SH, 4-sub. = OMe, OH, Cl, NMe2) have been synthesized, characterized and the geometry of the complexes were optimized by DFT. The chemical structure of synthesized imino flavone ligands and their complexes were characterized by elemental analysis, 1H NMR, 13C NMR, UV-visible, IR, ESI-mass spectral data, conductometric and magnetic measurements. The synthesized compounds have been screened for their in vitro antibacterial activities against bacteria Vibrio cholerae, Salmonella typhi, Staphylococcus aureus, Escherichia coli and antifungal activities against fungi Candida albicans and Aspergillus flavus by paper disc diffusion method. The complexes I-3, I-4, I-7 and I-8 showed good antimicrobial activities against pathogens.
Exploration of synthetic antioxidant flavonoid analogs as acetylcholinesterase inhibitors: an approach towards finding their quantitative structure–activity relationship
Karmakar, Abhijit,Ambure, Pravin,Mallick, Tamanna,Das, Sreeparna,Roy, Kunal,Begum, Naznin Ara
, p. 723 - 741 (2019/04/17)
The binding interactions between acetylcholinesterase (AChE) and a series of antioxidant flavonoid analogs were studied by fluorescence spectroscopic assay. The present study incorporated different classes of naturally occurring and synthetic flavonoid compounds like flavones, isoflavones, and chalcones as well as a few standard antioxidants. The AChE inhibitory (AChEI) activity of these compounds was further analyzed using in silico techniques, namely pharmacophore mapping, quantitative structure–activity relationship (QSAR) analysis, and molecular docking studies. We have also compared the AChE inhibitory and radical scavenging antioxidant activities of these compounds. Both the AChE inhibitory and antioxidant activities of these compounds were found to be highly dependent on their structural patterns. However, it was observed that, in general, flavones are comparatively better AChE inhibitors as well as antioxidants compared to chalcones. [Figure not available: see fulltext.].
Chalcone and flavonol copper(II) complexes containing schiff base co-ligand: Synthesis, crystal structures and catecholase-like activity
Kahrovi?, Emira,Zahirovi?, Adnan,Vi?njevac, Aleksandar,Osmankovi?, Irnesa,Turku?i?, Emir,Kurtagi?, Harun
, p. 195 - 207 (2018/08/06)
Four new heteroleptic copper(II) complexes having chalcone or flavonol ligands and Schiff base (N-phenyl-5-chlorosalicylideneimine) as co-ligand were prepared, chemically and structurally characterized and investigated as functional biomimetic catecholase models. The complexes were prepared by the solution synthesis and crystal and molecular structures were determined by X-ray diffraction. Complexes were chemically characterized by elemental analysis, infrared and electronic absorption spectroscopy as well as by electrochemical measurements. Copper(II) chalcone complexes, with square-pyramidal CuO4N core, are binuclear, featuring phenolate oxygen from the Schiff base as a bridging atom, while copper(II) flavonol complexes are mononuclear, and reveal a square planar CuO3N coordination core. Catalytic activity of the complexes in 3,5-di-tert-butylcatechol oxidation was confirmed by spectrophotometric and electrochemical measurements. Kinetic measurements revealed that the binuclear (chalcone-containing) complexes have enhanced catalytic activity as compared to the mononuclear Cu(II) flavonol complexes. Relatively high kcat values (300 – 750 h–1) confirmed their respectable biomimetic catecholase-like activity.
3′-Hydroxy-3,4′-dimethoxyflavone blocks tubulin polymerization and is a potent apoptotic inducer in human SK-MEL-1 melanoma cells
Estévez-Sarmiento, Francisco,Said, Mercedes,Brouard, Ignacio,León, Francisco,García, Celina,Quintana, José,Estévez, Francisco
, p. 6060 - 6070 (2017/10/13)
Flavonoids are naturally occurring polyphenolic compounds and are among the most promising anticancer agents. A series of flavonols and their 3-methyl ether derivatives were synthesized and assessed for cytotoxicity. It was found that 3′-hydroxy-3,4′-dime
Synthetic studies of fisetin, myricetin and nobiletin analogs and related probe molecules
Hiza, Aiki,Tsukaguchi, Yuta,Ogawa, Takahiro,Inai, Makoto,Asakawa, Tomohiro,Hamashima, Yoshitaka,Kan, Toshiyuki
, p. 1371 - 1396 (2016/10/12)
We synthesized a series of analogs of fisetin, myricetin and nobiletin, as well as related fluorescein- and biotin-based flavone-probe molecules, on a suitable scale for biological and structure-activity relationship studies.
Design, synthesis and biological activity of flavonoid derivatives as selective agonists for neuromedin U 2 receptor
Ma, Ming-Liang,Li, Ming,Gou, Jiao-Jiao,Ruan, Tian-Yu,Jin, Hai-Shan,Zhang, Ling-Hong,Wu, Liang-Chun,Li, Xiao-Yan,Hu, Ying-He,Wen, Ke,Zhao, Zheng
, p. 6117 - 6123 (2015/02/02)
Central neuromedin U 2 receptor (NMU2R) plays important roles in the regulation of food intake and body weight. Identification of NMU2R agonists may lead to the development of pharmaceutical agents to treat obesity. Based on the structure of rutin, a typi
