Polymeric proanthocyanidins from the bark of Hamamelis virginiana.
Polymeric proanthocyanidins were isolated from the bark of Hamamelis virginiana L. in yields of about 5 %. Fractionation yielded fractions with similar structures but different molecular weights with DP between 17-29 (thiolysis) and 11-20 (GPC). Polymers were composed predominantly of epicatechin and epigallocatechin as chain extension units at ratio of about 1.3:1. Terminal chain units were catechin (approximately 95 %) and gallocatechin (approximately 5 %). All chain extension units were completely galloylated at position O-3, while chain terminating units were not galloylated. Predominant interflavan linkages were 4 --> 8-bonds.
Dauer
A
A
Rimpler
H
H
Hensel
A
A
D000872:Anthocyanins / Q000737:chemistry / Q000302:isolation & purification*; D001704:Biopolymers / Q000737:chemistry; D029501:Hamamelis / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry*; D044945:Proanthocyanidins
D000872:Anthocyanins; D001704:Biopolymers; D044945:Proanthocyanidins; C013221:proanthocyanidin