New Diterpene Glycosides from Stevia rebaudiana Bertoni: Rebaudioside VIII and Rebaudioside IXd

With our interest of new diterpene glycosides with better taste profile than Rebaudioside M, we isolated and characterized two steviol glycosides with three additional glucose attached at the C-13 of Rebaudioside M or Rebaudioside D from an extract of Stevia rebaudiana Bertoni. Here we report the complete structure elucidations of diterpene glycosides on the basis of NMR experiments (H-1, C-13, COSY, HSQC-DEPT, HMBC, ID TOCSY, NOESY) and mass spectral data. Steviol glycosides that possess eight or nine glucose units are rarely reported in literature and could have an impact on the natural sweetener catalog.