New monoterpene glycoside esters and phenolic constituents of paeoniae radix, and increase of water solubility of proanthocyanidins in the presence of paeoniflorin

Seven new monoterpene glycoside esters related to paeoniflorin were isolate d from Paeoniae Radix, together with polymeric proanthocyanidins, polygallo ylglucoses and 48 known compounds (a benzoylsucrose, seven aromatic acids, adenosine, nine monoterpene glycosides, eight flavan-3-ols, a catechin dime r formed by oxidation, seven proanthocyanidins, three galloylsucroses, five galloylglucoses, and six ellagitannins). The structures of the new compoun ds were determined by spectral investigation including two-dimensional NMR techniques. In addition, increased water solubility of polymeric proanthocy anidin in the presence of paeoniflorin was examined by n-octanol-water part ition and H-1-NMR spectral experiments.