Studies in polyphenol chemistry and bioactivity. establishment of interflavan linkage regio- and stereochemistry by oxidative degradation of an O-alkylated derivative of procyanidin B(sub)2 to (R)-(--)-2,4-diphenylbutyric acid

Results demonstrate that procyanidin B(sub)2 exhibits a 4beta,8 interflavan bond. A procedure for an exhaustive deoxygenation of a single flavonoid in a partially protected dimeric structure is described.