88244-66-0Relevant academic research and scientific papers
METHOD FOR PRODUCING 4- TO 6-MER OF CATECHIN AND EPICATECHIN
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Paragraph 0059; 0060, (2016/10/08)
PROBLEM TO BE SOLVED: To provide a method for producing a 4- to 6-mer of catechin or epicatechin optical selectively and efficiently. SOLUTION: The 4- to 6-mer of catechin can be produced efficiently by using a 3- to 5-mer of catechin as a nucleophile, and a catechin monomer as an electrophile, and by reacting them in the presence of silver triflate (Ag(CF3SO3)). Furthermore, the 4- to 6-mer of epicatechin can be produced efficiently by using a 2-mer of epicatechin as a nucleophile, and a 2- to 4-mer of epicatechin monomer as an electrophile, and reacting them in the presence of zinc triflate (Zn(CF3SO3)2). SELECTED DRAWING: None COPYRIGHT: (C)2016,JPO&INPIT
Versatile synthesis of epicatechin series procyanidin oligomers, and their antioxidant and DNA polymerase inhibitory activity
Saito, Akiko,Mizushina, Yoshiyuki,Tanaka, Akira,Nakajima, Noriyuki
experimental part, p. 7422 - 7428 (2009/12/24)
Proanthocyanidins, known as condensed tannins or oligomeric flavonoids, exist in many edible plants and show various interesting biological activities. We have developed a simple and versatile method of synthesizing procyanidin oligomers consisting of (-)
Synthesis of Condensed Tannins. Part 13. The First 2,3-trans-3,4-cis-Procyanidins: Sequence of Units in a 'Trimer' of Mixed Stereochemistry
Delcour, Jan A.,Serneels, Edward J.,Ferreira, Daneel,Roux, David G.
, p. 669 - 676 (2007/10/02)
The condensation of (+)-leucocyanidin with (-)-epicatechin initiates a succession of substitutions leading mainly to the introduction of -2,3-trans-3,4-procyanidin units, but also to the incorporation of 'terminal' moieties which possess the hitherto unique 3,4-cis-procyanidin configuration.The bonding patterns in the products, and also the sequence of units in one of the 'trimers' of mixed stereochemistry, are resolved by (1)H n.m.r. spectroscopy through selective use of solvents at elevated temperatures.
Synthesis of Condensed Tannins. Part 9. The Condensation Sequence of Leucocyanidin with (+)-Catechin and with the Resultant Procyanidins
Delcour, Jan. A.,Ferreira, Daneel,Roux, David G.
, p. 1711 - 1717 (2007/10/02)
Molar equivalents of synthetic (2R,3S,4R of S)-leucocyanidin and (+)-catechin condense with exceptional rapidity at pH 5 under ambient conditions to give the all-trans-- and -bi- (procyanidins B3, B6) the all-trans-- and -tri- (procyanidin C2, and novel isomer), and the presumed all-trans--linked tetraflavanoid analogue in the proportions 10:1:12:1:3.The facility and sequence of these condensations correlate with the observed absence of leucocyanidins (flavan-3,3',4,4',5,7-hexaols) and also the dominance of related condensed tannins in plant extracts.
