480-41-1Relevant academic research and scientific papers
Synthesis, structural elucidation and antiradical activity of a copper (II) naringenin complex
Celiz, Gustavo,Suarez, Sebastián A.,Arias, Analía,Molina, José,Brondino, Carlos D.,Doctorovich, Fabio
, p. 595 - 610 (2019)
Coupling the extraction and derivatization of flavonoids to the Citrus processing industry is attractive from both the environmental and economic points of view. In the present work, the flavonoid naringin, obtained by “green” extraction with a water:ethanol mixture from waste grapefruit industry, was hydrolyzed to obtain naringenin. This flavonoid was used to synthesize the complex trans-di(aqua) bis(7-hydroxy-2-(4-hydroxyphenyl)-4-oxo-5-chromanolato) copper (II). This compound was characterized by spectroscopic techniques (UV/Vis, IR, Raman, NMR and EPR), and by thermal analysis (TG and DSC). Then, a monocrystal of the complex obtained by dissolution and recrystallization in DMF was analyzed by single crystal X-ray diffraction. This is the first report of the crystal structure of a Citrus flavonoid complex. Additionally, its antiradical activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) was determined and compared with that for naringenin, demonstrating that coordination to copper enhances the antiradicalar activity of naringenin. According to the Mulliken population analysis conducted, by copper favors the delocalization and stabilization of the produced radical, since it acts as an electronic density acceptor.
Development and evaluation of an HPLC method for accurate determinations of enzyme activities of naringinase complex
Ni, Hui,Xiao, An-Feng,Wang, Ya Qi,Chen, Feng,Cai, Hui-Nong,Su, Wen-Jun
, p. 10026 - 10032 (2013)
An HPLC method that can separate naringin, prunin, and naringenin was used to help accurately measure the activities of naringinase and its subunits (α-l-rhamnosidase and β-d-glucosidase). The activities of the naringinase and β-d-glucosidase were determined through an indirect calculation of the naringenin concentration to avoid interference from its poor solubility. The measured enzymatic activities of the naringinase complex, α-l-rhamnosidase, and β-d-glucosidase were the as same as their theoretical activities when the substrates' (i.e., naringin or prunin) concentrations were 200 μg/mL, and the enzyme concentrations were within the range of 0.06-0.43, 0.067-0.53, and 0.15-1.13 U/mL, respectively. The β-d-glucosidase had a much higher Vmax than either naringinase or α-l-rhamnosidase, implying the hydrolysis of naringin to prunin was the limiting step of the enzyme reaction. The reliability of the method was finally validated through the repeatability test, indicating its feasibility for the determinations of the naringinase complex.
Sulfation of naringenin by Cunninghamella elegans
Ibrahim, Abdel-Rahim S.
, p. 209 - 212 (2000)
A new flavonoid sulfate, naringenin-7-sulfate, was obtained by fermentation of naringenin using the fungus Cunninghamella elegans NRRL 1392 in 23% yield. Structural elucidation of the metabolite was achieved using EIMS, UV, IR, 1D and 2D NMR spectroscopy beside acid and enzyme hydrolyses. (C) 2000 Elsevier Science Ltd.
GLUCOSYLATED FLAVONOIDS AND OTHER PHENOLIC COMPOUNDS FROM SORGHUM
Gujer, Rene,Magnolato, Daniele,Self, Ron
, p. 1431 - 1436 (1986)
The principal tannin constituents of sorghum are proanthocyanidins or condensed tannins.Analysis of the methanolic extract of a Hungarian sorghum (szegedi toerpe) containing 6percent catechin equivalents of tannins resulted in the separation and purification of 4 procyanidins having the basic formula epicatechin-(epicatechin)n-catechin and one procyanidin trimer corresponding to epicatechin-catechin-epicatechin.Apart from these procyanidins, the monomeric flavonoids eriodictyol 5-glucoside and (+)-taxifolin 7 glucoside together with their aglycones eriodictyol and taxifolin were found.Glucosylated dimeric and trimeric flavanoids with eriodictyol or eriodictyol 5-glucoside as the lower unit were also identified with the help of negative ion FABMS.Polymeric flavonoids formed between a chalcone and a flavonoid, as yet not identified, are also present in the grain. Key Word Index - Sorghum; Gramineae; flavanoids; glycosides; new oligomer glucosides; procyanidins; chalchone identification.
Design, synthesis, and cholinesterase inhibition assay of liquiritigenin derivatives as anti-Alzheimer's activity
Guan, Liping,Jia, Jinjing,Jiang, Haiying,Peng, Dingxin,Zhang, Li
, (2021/10/01)
The marine environment is a rich resource for discovering functional materials, and seaweed is recognized for its potential use in biology and medicine. Liquiritigenin has been isolated and identified from Sargassum pallidum. To find new anti-Alzheimer's activity, we designed and synthesized thirty-two 7-prenyloxy-2,3-dihydroflavanone derivatives (3a-3p) and 5-hydroxy-7-prenyloxy-2,3-dihydro-flavanone derivatives (4a-4p) as cholinesterases inhibitors based on liquiritigenin as the lead compound. Inhibition screening against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) indicated that all synthesized compounds possessed potent AChE inhibitory activity and moderated to weak BuChE inhibitory activity in vitro. Kinetic studies demonstrated that compound 4o inhibited AChE via a dual binding site ability. In addition, all compounds displayed the radical scavenging effects. Finally, the molecular docking simulation of 4o in AChE active site displayed good agreement with the obtained the pharmacological results.
Flavanone compound as well as preparation method and application thereof
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Paragraph 0202-0205, (2021/04/17)
The invention belongs to the technical field of medicines, and particularly relates to a flavanone compound as well as a preparation method and application thereof. Specifically disclosed is a compound represented by formula (I) or a pharmaceutically acceptable salt thereof. The compound shown in the formula (I) can target hURAT1 and/or GLUT9, so that uric acid excretion is promoted, and the effect of reducing uric acid is achieved. The compound can be used for preparing medicines for treating and/or preventing and/or delaying and/or adjunctively treating and/or treating diseases related to hURAT1/GLUT9 activity, and has a good application prospect in preventing or treating diseases (such as gout, gouty arthritis, uric acid kidney stone and the like) related to hyperuricemia.
Discovery of Novel Bacterial Chalcone Isomerases by a Sequence-Structure-Function-Evolution Strategy for Enzymatic Synthesis of (S)-Flavanones
Bornscheuer, Uwe T.,Brückner, Stephan I.,Gei?ler, Torsten,Gross, Egon,Hartmann, Beate,Ley, Jakob P.,Meinert, Hannes,R?ttger, Carsten,Schuiten, Eva,Yi, Dong,Zirpel, Bastian
supporting information, p. 16874 - 16879 (2021/07/06)
Chalcone isomerase (CHI) is a key enzyme in the biosynthesis of flavonoids in plants. The first bacterial CHI (CHIera) was identified from Eubacterium ramulus, but its distribution, evolutionary source, substrate scope, and stereoselectivity are still unclear. Here, we describe the identification of 66 novel bacterial CHIs from Genbank using a novel Sequence-Structure-Function-Evolution (SSFE) strategy. These novel bacterial CHIs show diversity in substrate specificity towards various hydroxylated and methoxylated chalcones. The mutagenesis of CHIera according to the substrate binding models of these novel bacterial CHIs resulted in several variants with greatly improved activity towards these chalcones. Furthermore, the preparative scale conversion catalyzed by bacterial CHIs has been performed for five chalcones and revealed (S)-selectivity with up to 96 % ee, which provides an alternative biocatalytic route for the synthesis of (S)-flavanones in high yields.
Novel chromenone derivatives having substituted biphenyl group and a pharmaceutical composition for prevention or treatment of allergic diseases compring the same
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Paragraph 0157-0164; 0166-0170, (2020/11/26)
The present invention relates to: a novel chromenone derivative compound capable of effectively suppressing an allergic immune response by inhibiting signal transduction mediated by thymic stromal lymphopoietin (TSLP); and a pharmaceutical composition capable of fundamentally preventing or treating various allergic diseases by using the same.COPYRIGHT KIPO 2021
Covalent Immobilization of Naringinase over Two-Dimensional 2D Zeolites and its Applications in a Continuous Process to Produce Citrus Flavonoids and for Debittering of Juices
Carceller, Jose Miguel,Martínez Galán, Julián Paul,Monti, Rubens,Bassan, Juliana Cristina,Filice, Marco,Yu, Jihong,Climent, María J.,Iborra, Sara,Corma, Avelino
, p. 4502 - 4511 (2020/06/08)
The crude naringinase from Penicillium decumbens and a purified naringinase with high α-L-rhamnosidase activity could be covalently immobilized on two-dimensional zeolite ITQ-2 after surface modification with glutaraldehyde. The influence of pH and temperature on the enzyme activity (in free and immobilized forms) as well as the thermal stability were determined using the specific substrate: p-nitrophenyl-alpha-L-rhamnopyranoside (Rha-pNP). The crude and purified naringinase supported on ITQ-2 were applied in the hydrolysis of naringin, giving the flavonoids naringenin and prunin respectively with a conversion '90 percent and excellent selectivity. The supported enzymes showed long term stability, being possible to perform up to 25 consecutive cycles without loss of activity, showing its high potential to produce the valuable citrus flavonoids prunin and naringenin. We have also succeeded in the application of the immobilized crude naringinase on ITQ-2 for debittering grapefruit juices in a continuous process that was maintained operating for 300 h, with excellent results.
Site-selective synthesis of acacetin and genkwanin through lipase-catalyzed deacetylation of apigenin 5,7-diacetate and subsequent methylation
Fujita, Rie,Hanaya, Kengo,Higashibayashi, Shuhei,Mandal, Susanta,Shoji, Mitsuru,Sugai, Takeshi
, p. 638 - 648 (2019/07/31)
Candida antarctica lipase B-catalyzed deacetylation proceeded with high site-selectivity on the C-4′ acetyl group in apigenin triacetate to give apigenin 5,7-diacetate. Methylation of the liberated hydroxy group with the combination of trimethyloxonium tetrafluoroborate (Meerwein reagent) and 1,8-bis(dimethylamino)naphthalene (proton sponge) in CH2Cl2 proceeded in a quantitative manner to give the product methylated at the C-4′ hydroxy group (acacetin 5,7-diacetate). Even with the same precursor, a different methylation product at the C-7 hydroxy group (genkwanin 4′,5-diacetate) was obtained in 86% yield by applying iodomethane and Cs2CO3 in dimethyl sulfoxide (DMSO). The methylated products were deprotected to form acacetin and genkwanin. We inferred that the latter unexpected methylation was ascribable to the intermolecular migration of an acetyl group from C-7 to C-4′. DFT calculations indicated that the C-7 phenoxide ion was 12.6 kJ/mol more stable than the initially formed C-4′ phenoxide ion.
