A semisynthetic approach for the simultaneous reaction of grape seed polymeric procyanidins with catechin and epicatechin to obtain oligomeric procyanidins in large scale

The paper describes a semisynthetic approach for obtaining oligomeric procyanidins from grape seed polymeric procyanidins in large scale. The proposed method allows for the simultaneous reaction of grape seed polymeric procyanidins with catechin and epicatechin to obtain bioactive gallated dimers in high production. The resulting oligomers were largely isolated by preparative-HPLC under optimized conditions, and 13 individual procyanidins were identified and prepared with high yield and purity. The semisynthetic products could be used for exploring structure-activity relationships and further bioactivity studies.