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Proanthocyanidin B6
Procyanidin B6 is a B type proanthocyanidin. Procyanidin B6 is a catechin-(4α→6)-catechin dimer. It can be found in grape seeds and in beer. Chemical synthesis Molar equivalents of synthetic (2R,3S,4R or S)- and (+)- condense with exceptional rapidity at pH 5 under ambient conditions to give the all-trans- ,8 and ,6bi- +)-catechins([...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B Type Proanthocyanidin
B type proanthocyanidins are a specific type of proanthocyanidin, which are a class of flavanoids. They are oligomers of flavan-3-ols. Dimeric B type proanthocyanidins These molecules have the molecular formula C30H26O12 (molar mass : 578.52 g/mol, exact mass : 578.142426). Molecules with 4→8 bonds The 4-8 bond can be in the alpha or in the beta position. * Procyanidin B1 or epicatechin-(4β→8)-catechin * Procyanidin B2 or (−)-epicatechin-(4β→8)-(−)-epicatechin * Procyanidin B3 or catechin-(4α→8)-catechin * Procyanidin B4 or catechin-(4α→8)-epicatechin Molecules with 4→6 bonds * Procyanidin B5 or epicatechin-(4β→6)-epicatechin * Procyanidin B6 or catechin-(4α→6)-catechin * Procyanidin B8 or catechin-(4α→6)-epicatechin Chemistry B-type procyanidin (catechin dimer) can be converted to A-type procyanidin by radical oxidation. Dimeric proanthocyanidins can also be synthesized with procyanidin-rich grape seed extracts reacted with flavan-3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catechin
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 (-)-epic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leucocyanidin
Leucocyanidin is a colorless chemical compound that is a member of the class of natural products known as leucoanthocyanidins. Chemistry (+)-Leucocyanidin can be synthesized from (+)- dihydroquercetin by reduction with sodium borohydride. Molar equivalents of synthetic (2R,3S,4R or S)-leucocyanidin and (+)- catechin condense with exceptional rapidity at pH 5 under ambient conditions to give the all-''trans''- ,8 and ,6bi- +)-catechins( procyanidins B3, B6) the all-''trans''- ,8:4,8 and ,8:4,6tri- +)-catechins( procyanidin C2 and isomer). Metabolism Leucocyanidin oxygenase uses leucocyanidin, 2-oxoglutarate, and O2 to produce ''cis''-dihydroquercetin, ''trans''- dihydroquercetin (taxifolin), succinate, CO2, and H2O. Leucoanthocyanidin reductase (LAR or leucocyanidin reductase LCR) uses (2''R'',3''S'')- catechin, NADP+, and H2O to produce 2,3-''trans''-3,4-cis-leucocyanidin, NADPH, and H+. Its gene expression has been studied in developing grape berries and grapevin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procyanidin B3
Procyanidin B3 is a B type proanthocyanidin. Procyanidin B3 is a catechin dimer ( catechin-(4α→8)-catechin). Natural occurrences It can be found in red wine, in barley, in beer, in peach or in ''Jatropha macrantha'', the Huanarpo Macho. Health effects It has been identified as a hair-growth stimulant. Chemical synthesis Molar equivalents of synthetic (2R,3S,4R or S)-leucocyanidin Leucocyanidin is a colorless chemical compound that is a member of the class of natural products known as leucoanthocyanidins. Chemistry (+)-Leucocyanidin can be synthesized from (+)-dihydroquercetin by reduction with sodium borohydride. Mola ... and (+)- catechin condense with exceptional rapidity at pH 5 under ambient conditions to give the all-trans- ,8 and ,6bi- +)-catechins(procyanidins B3, B6) the all-trans- ,8:4,8 and ,8:4,6tri- +)-catechins( procyanidin C2 and isomer). See also * Phenolic content in wine References Procyanidin dimers {{Aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procyanidin C2
Procyanidin C2 is a B type proanthocyanidin trimer, a type of condensed tannin. Natural occurrences Procyanidin C2 is found in grape seeds (''Vitis vinifera'') and wine, in barley (''Hordeum vulgare''), malt and beer, in ''Betula spp.'', in ''Pinus radiata'', in '' Potentilla viscosa'', in '' Salix caprea'' or in '' Cryptomeria japonica''. The contents in barley grain of trimeric proanthocyanidins, including procyanidin C2, range from 53 to 151 μg catechin equivalents/g. Possible health uses Proanthocyanidin oligomers, extracted from grape seeds, have been used for the experimental treatment of androgenic alopecia. When applied topically, they promote hair growth ''in vitro'', and induce anagen ''in vivo''. Procyanidin C2 is the subtype of extract most effective. Experiments showed that both procyanidin C2 and Pycnogenol (French maritime pine bark extract) increase TNF-α secretion in a concentration- and time-dependent manner. These results demonstrate that procyanidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
