Chemical studies on the oriental plant drugs—XXXIII

The absolute structure of paeoniflorin, a major principle of Chinese Paeony root (Paonia albiflora Pallas (Paeoniaceae)) was established as I and as shown in Chart 2 by the X-ray analysis of a bromo derivative (VI) of product K2 acetate (V). The absolute structures of the minor constituents, albiflorin (VII), oxypaeoniflorin (IX) and benzoylpaeoniflorin (X) were also established on the basis of the established structure of paeoniflorin.