Polymeric Proanthocyanidins: Interflavanoid Linkage Isomerism in (Epicatecbin .4).( epicatechin -4)-catecbin Procyanidins
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Linkage Isomerism in Trimeric and Polymeric 2.3.cis-Procyanidins
Four procyanidin trimers have been isolated and their structures unequivocally established as: epicatechin(4~+8)'epicatechin-(4~+8)-catechin (5); epicatechin-(4~-+6)-epicatechin-(4~-8)-catechin (6); epicatechin(4~8)-epicatechin-(4~6)-catechin (7); and epicatechin-(4~-8)-epicatechin-(4~-+8).epic8techin (13), The presence of the first three trimers in Pinus tBeds phloem. and the isolation of both...
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The presence of the procyanidins epicatechin-( 4j3-8)-catechin. epicatechin..{ 4j3-6)-catechin. catechin( 4a-8)-catechin. epicatechin-( 4j3-8 >-epicatechin-( 4j3-8)-epicatechin-{ 4138)-catechin. and epicatechin-(4j3-8)-epicatechin-(4j3-6)catechin in tile phloem of PillU.f raeda demonstrated heterogeneity in the location of the interftavanoid bonds in oligomeric pro...
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