664351-43-3Relevant articles and documents
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.
Scale-Up Syntheses of Two Naturally Occurring Procyanidins: (-)-Epicatechin-(4β,8)-(+)-catechin and (-)-Epicatechin-3-0-galloyl- (4β, 8)-(-)-epicatechin-3-0-gallate
Sharma, Pradeep K.,Kolchinski, Alexander,Shea, Helene A.,Nair, Jayesh J.,Gou, Yanni,Romanczyk Jr., Leo J.,Schmitz, Harold H.
, p. 422 - 430 (2012/12/31)
A scaleable process for the synthesis of two naturally occurring procyanidins, namely (-)-epicatechin-(4β,8)-(+)-catechin (1) and(-)-epiratechin-3-O-galloyl-(4β,8)-(-)-epicatechin-3-O-gallate (2), is described. The key steps were highlighted by improvements for the benzylation of (+)-catechin (3), stereo-selective reduction of the C-3 keto group of (2A)-5,7,3′,4′-tetrakis(benzyloxy)flavan-3-one (10), and coupling between 4-hydroxyethoxy-5,7,3′,4′-tetra-O-benzyl-(-)-epicatechin (11) and 5,7,3′,4′-tetra-O-benzyl-(+)-catechin (4) or 5,7,3′,4′-tetra-O-benzyl-(-)-epicatechin (6), respectively. The debenzylation performed in a biphasic system resulted in an improved yield and purity of the target compounds. The chemistry was scaled-up to produce multigram quantities of the title compounds (1 and 2) for various in vitro, ex vivo, and in vivo studies. Moreover, the scale-up process provided a detailed description for the preparation of multihundred to kilogram scale quantities of intermediates used in the synthesis of these two titled procyanidins.
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.
