CHEMICAL STUDIES ON CRUDE DRUG PROCESSING .9. ON THE CONSTITUENTS OF REHMANNIAE RADIX .3. ABSOLUTE STEREOSTRUCTURES OF REHMAIONOSIDE-A, REHMAIONOSIDE-B, AND REHMAIONOSIDE-C, AND REHMAPICROSIDE, BIOLOGICALLY-ACTIVE IONONE GLUCOSIDES AND A MONOTERPENE GLUCOSIDE ISOLATED FROM CHINESE REHMANNIAE RADIX

Following the characterization of the iridoid and iridoid glycoside co nstituents in Chinese Rehmanniae Radix, the dried root of Rehmannia gl utinosa LIBOSCH. [Kan-jio in Japanese], we investigated the structures of biologically active ionone glucosides, rehmaionosides A, B, and C, and a monoterpene glucoside, rehmapicroside. Their absolute stereostr uctures were determined on the basis of chemical and physicochemical e vidence, which included the result of application of the exciton chira lity method to the allylic benzoyl derivatives.