Tannins and Related Compounds. LX. : Isolation and Characterization of Proanthocyanidins with a Doubly-Linked Unit from Vaccinium vitis-idaea L.

Abstract

New proanthocyanidin trimers (14 and 15) and tetramers (16 and 17) have been isolated from the whole body of Vaccinium vitis-idaea L. (Ericaceae). The structures of these proanthocyanidins were established by thiolytic degradation and by analyses of the proton and carbon-13 nuclear magnetic resonance spectra. In addition, the presence of (-)-epicatechin (1), (+)-catechin (2), (-)-epigallocatechin (3), (+)-gallocatechin (4), procyanidins B-1 (5), B-3 (6), A-1 (8), and A-2 (9), and cinnamtannins B₁ (10), D₁ (11), B₂ (12), D₂(13) in this plant was demonstrated.