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Epicatechin
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids. The name of the catechin chemical family derives from ''catechu'', which is the tannic juice or boiled extract of ''Mimosa catechu'' (''Acacia catechu'' L.f). Chemistry Catechin possesses two benzene rings (called the A- and B-rings) and a dihydropyran heterocycle (the C-ring) with a hydroxyl group on carbon 3. The A-ring is similar to a resorcinol moiety while the B-ring is similar to a catechol moiety. There are two chiral centers on the molecule on carbons 2 and 3. Therefore, it has four diastereoisomers. Two of the isomers are in trans configuration and are called ''catechin'' and the other two are in cis configuration and are called ''epicatechin''. The most common catechin isomer is (+)-catechin. The other stereoisomer is (-)-catechin or ''ent''-catechin. The most common epicatechin isomer is (-)-epicatechin (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavan-3-ol
Flavan-3-ols (sometimes referred to as flavanols) are a subgroup of flavonoids. They are derivatives of flavans that possess a 2-phenyl-3,4-dihydro-2''H''-chromen-3-ol skeleton. Flavan-3-ols are structurally diverse and include a range of compounds, such as catechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, proanthocyanidins, theaflavins, thearubigins. They are found in most plants and have a role in plant defense. Chemical structure The single-molecule (monomer) catechin, or isomer epicatechin (see diagram), adds four hydroxyls to flavan-3-ol, making building blocks for concatenated polymers ( proanthocyanidins) and higher order polymers ( anthocyanidins). Flavan-3-ols possess two chiral carbons, meaning four diastereoisomers occur for each of them. They are distinguished from the yellow, ketone-containing flavonoids such as quercitin and rutin, which are called flavonols. Early use of the term bioflavonoid was imprecisely applied to include t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
