Stevisalioside A, a novel bitter-tasting ent-atisene glycoside from the roots of Stevia salicifolia.

A new acetylated ent-atisene glycoside, stevisalioside A [1], has been isolated as a bitter-tasting principle from Stevia salicifolia roots. The structure was established by the interpretation of spectral data, with the nmr assignments of this compound being based on H-1-H-1 COSY, H-1-C-13 HETCOR, and selective INEPT experiments. A rearrangement product 4 of the aglycone moiety obtained by alkaline hydrolysis supported the structure of 1. This is the first report of the occurrence of an atisane-type diterpene from the genus Stevia.