Procyanidin B6 is a

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/m ...

. Procyanidin B6 is a

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 ...

-(4α→6)-catechin dimer. It can be found in grape seedsProcyanidin dimers and trimers from grape seeds. Jorge M. Ricardo da Silva, Jacques Rigaud, Véronique Cheynier, Annie Cheminat and Michel Moutounet, 1991
/ref> and in beer.

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 (+)-

condense with exceptional rapidity at pH 5 under ambient conditions to give the all-trans- ,8 and ,6bi- +)-catechins( procyanidins B3 and B6) the all-trans- ,8:4,8 and ,8:4,6tri- +)-catechins(

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 '' ...

and isomer).Synthesis of condensed tannins. Part 9. The condensation sequence of leucocyanidin with (+)-catechin and with the resultant procyanidins. Jan. A. Delcour, Daneel Ferreira and David G. Roux, J. Chem. Soc., Perkin Trans. 1, 1983, pages 1711-1717,

References

{{procyanidin Procyanidin dimers