Dihydroisocoumarin Constituents from the Leaves of Hydrangea macrophylla var. thunbergii (2). : Absolute Stereostructures of Hydrangenol, Thunberginol I, and Phyllodulcin Glycosides and Isomerization Reaction at the 3-Positions of Phyllodulcin and Its Glycosides

抄録

Following the characterization of 3S-phyllodulcin, 3R- and 3S-phyllodulcin 3'-O-glucosides, and 3R- and 3S- thunberginol H 8-O-glucosides, six new dihydroisocoumarin glycosides, 3R- and 3S-hydrangenol 4'-O-apiosylglucosides, 3R- and 3S-thunberginol I 4'-O-glucosides, thunberginol I 8-O-glucoside, and 3S-phyllodulcin 8-O-glucoside, were isolated from the dried leaves of Hydrangea macrophylla var. thunbergii and their structures were determined on the basis of chemical and physicochemical evidence. In addition, isomerization reaction at the 3- positions of phyllodulcin and its glycosides was examined.