The absolute configuration of 1 was gleaned from ECD and NOESY data (Figure ). Due to a highamplitude negative Cotton effect (CE) in the diagnostic region 220~240 nm (Figure ), the C-4 aryl functionalities in both units II and III were determined to be -configured. The absolute configuration of C-4 in units I and II were, thus, assigned as S and R, respectively (note the change in Cahn-Ingold-Prelog priorities due to different connections, causing different stereodescriptors for spatially identical configurations at both C-4). Taking into account the 2,4-cis configuration in A-type PACs, units I/II and II/III had to be doubly connected via (2O5,46) and (2O7,48) IFLs, respectively. A NOESY correlation between II-H-3 and III-H-6 indicated a 3,4-trans configuration in the F-ring, thus II-C-3 was S-configured. Comparison of the tendency of ECD curves of 1 in the diagnostic region 280~300 nm with those of procyanidin A2 (5) and procyanidin A5 (7) 8 revealed that 1 is closely mirror symmetric to 7 (Figure ). Thus, the partial structures of units II and III in 1 were assigned to be enantiomeric to those in 7. This was consistent with the R-configuration of III-C-2 deduced from the negative CE at 280~300 nm, and the NOESY correlation of II-H-4 and III-H-6. Finally, I-H-3 had to be -oriented based on NOESY correlations between I-H-3 and both III-H-2 and III-H-6. Accordingly, 1 was assigned as ent-epicatechin-(2O5,46)-ent-epicatechin-(2O7,48)-epicatechin.