29106-51-2Relevant academic research and scientific papers
Hemisynthesis and structural characterization of flavanol-(4,8)-vitisins by mass spectrometry
Nave, Frederico,Teixeira, Natercia,Mateus, Nuno,de Freitas, Victor
, p. 1964 - 1970 (2010)
Vitisins constitute the major group of pyranoanthocyanins naturally occurring in red wines. Regarding their chemical structure, only carboxypyranoanthocyanins have been detected and quantified in red wines, but no vitisin with substitutions in the carbons of the A ring has been identified. However, considering the chemical reactions that take place in red wine, the existence of flavan-3-ol-(4,6/8)-vitisins is expected. This paper reports for the first time the structural identification of catechin-vitisin A and catechin-vitisin B based on their mass data and fragmentation patterns. This work also provides some chromatographic and visible spectroscopic features of these pigments and documents the existence of both in red table wines. Moreover, it is also proposed that Cat-Vit A pigments arise from the cycloaddition of pyruvic acid to an anthocyanin moiety of a flavanolanthocyanin adduct rather than by direct nucleophilic attack of a vitisin A on the carbocation C4 of catechin.
COMPOSITION FOR PROMOTING EXPRESSION OF AQUAPORIN 3, AND USE THEREOF
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Paragraph 0239; 0243, (2020/09/22)
The purpose of the present invention is to provide a specific composition for promoting expression of aquaporin 3, and use thereof. The present invention relates to a composition for promoting expression of aquaporin 3, the composition including a galloyl group-containing flavan-3-ol monomer and/or a galloyl group-containing flavan-3-ol polymer as an active ingredient.
Synthesis of procyanidin B1, B2, and B4 and their anti-inflammatory activity: The effect of 4-alkoxy group of catechin and/or epicatechin electrophiles for condensation
Katoh,Oizumi,Mohri,Hirota,Makabe
scheme or table, p. 233 - 238 (2012/07/28)
Abstract: Procyanidin B1, B2, and B3 were synthesized based on a Yb(OTf)3 catalyzed equimolar condensation using methoxy and/or 4-(2-ethoxyethoxy) drivatives as electrophiles. The anti-inflammatory effect of synthetic procyanidin B1, B2, and B4 on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation of mouse ears was examined. Procyanidin B1, B2, B 4 suppressed TPA-induced inflammation of mouse ears by 48%, 34%, and 29%, respectively, at a dose of 200 μg. Their activities are stronger than those of indomethacin and glycyrrhetinic acid, the normally used antiinflammatory agent.
An efficient synthesis of procyanidins using equimolar condensation of catechin and/or epicatechin catalyzed by ytterbium triflate
Mohri, Yoshihiro,Sagehashi, Masayoshi,Yamada, Taiji,Hattori, Yasunao,Morimura, Keiji,Hamauzu, Yasunori,Kamo, Tsunashi,Hirota, Mitsuru,Makabe, Hidefumi
experimental part, p. 549 - 563 (2009/12/07)
Stereoselective synthesis of catechin and epicatechin dimers under intermolecular condensation of equimolar amount of catechin derivatives catalyzed by Yb(OTf)3. The coupled products were successfully converted to procyanidins B1, B2, B3, and B4, respectively. Procyanidins B1, B2, B3, and B4 could be used as standard compounds for identifying the polyphenols in natural source.
An efficient synthesis of procyanidins. Rare earth metal Lewis acid catalyzed equimolar condensation of catechin and epicatechin
Mohri, Yoshihiro,Sagehashi, Masayoshi,Yamada, Taiji,Hattori, Yasunao,Morimura, Keiji,Kamo, Tsunashi,Hirota, Mitsuru,Makabe, Hidefumi
, p. 5891 - 5894 (2008/02/09)
Stereoselective synthesis of catechin and epicatechin dimers under intermolecular condensation is achieved by an equimolar amount of coupling catalyzed by Yb(OTf)3. The coupled products were successfully converted to procyanidin B1, B2, B3, and B4.
An improved synthesis of procyanidin dimers: Regio- and stereocontrol of the interflavan bond
Tarascou, Isabelle,Barathieu, Karine,Andre, Yann,Pianet, Isabelle,Dufourc, Erick J.,Fouquet, Eric
, p. 5367 - 5377 (2007/10/03)
A direct and general synthesis of procyanidin dimers B1, B2, B3 and B4 (10a-d) is presented. The approach is based on the stoichiometric coupling of two protected monomeric units (the nucleophilic 2a-b and electrophilic 4a-b partners) and deals with the regio- and stereocontrol of the C4-C8 interflavan bond as well as the control of the degree of oligomerization. The synthesis involves a five-step pathway starting from the native catechin (1a) or epicatechin (1b) to the fully deprotected dimers 10a-d. Furthermore, the process appears to be iterative as the coupling intermediates 9a-d themselves can be readily used in further selective syntheses of trimers or higher oligomers. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
Polyphenols from peanut skins and their free radical-scavenging effects
Lou, Hongxiang,Yuan, Huiqing,Ma, Bin,Ren, Dongmei,Ji, Mei,Oka, Syuichi
, p. 2391 - 2399 (2007/10/03)
Separation of the water-soluble fraction of peanut skins led to the isolation of five proanthocyanidins. Based on the spectroscopic investigation and partial acid catalyzed degradation, their structures were determined to be epicatechin-(2β→O→7, 4β→6)-[epicatechin- (4β→8)]-catechin (1), epicatechin-(2β→O→7, 4β→8) epicatechin-(4β→8)-catechin-(4β→8)- epicatechin (2), and procyanidins B2 (3), B3 (4) and B4 (5). The absolute configuration of the new compounds was determined from their circular dichroism curves and the 1H NMR spectra of analysis of flavan-3-ols formed by thiolytic degradation of 1 and 2 in the presence of a chiral dirhodium complex (dirhodium tetra-(R)-(trifluoromethyl) phenyl acetate).
Synthetic studies of proanthocyanidins. Part 4. The synthesis of procyanidin B1 and B4: TMSOTf-catalyzed cyclization of catechin and epicatechin condensation
Saito, Akiko,Nakajima, Noriyuki,Tanaka, Akira,Ubukata, Makoto
, p. 287 - 298 (2007/10/03)
Highly stereoselective synthesis of 3,4-trans series of (+)-catechin and (-)-epicatechin dimers under intramolecular condensation is described. Intramolecular condensation achieved an equimolar amount of coupling with 3,4-trans stereoselectivity and we succeeded in the synthesis of two 3,4-trans natural procyanidins, procyanidin-B1 and B4.
Oligomeric flavanoids. Part 27. Interflavanyl bond formation in procyanidins under neutral conditions
Steynberg, Petrus J.,Nel, Reinier J.J.,Van Rensburg, Hendrik,Bezuidenhoudt, Barend C.B.,Ferreira, Daneel
, p. 8153 - 8158 (2007/10/03)
Dimethyl(methylthio)sulfonium tetrafluoroborate (DMTSF) and silver tetrafluoroborate (AgBF4) activate the C4-S bond in the 4-thioethers of flavan-3-ols toward carbon nucleophiles to permit formation of the interflavanyl bond in procyanidins under neutral conditions.
Deuterium labeled procyanidin syntheses
Pierre, Marie-Clotilde,Cheze, Catherine,Vercauteren, Joseph
, p. 5639 - 5642 (2007/10/03)
Deuterium-labeled procyanidins have been prepared by hemisynthesis from taxifolin in order to investigate their metabolism in human. The structures of the desired deuterated natural compounds B3 10D (R1 = D, R2 = H) and B4 13D (R1 = D, R2 = H) were proven by spectroscopic and physical properties means, including 2H NMR spectrum. By-products with unatural absolute configuration at some centers were also formed along the process and were characterised.
