From the commercial extract of the leaves of Stevia rebaudiana, a diterpene glycoside was isolated which was characterized as 13-[(2-O-βD-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl) ester (1); also
known as rebaudioside E. The complete 1H and 13C NMR assignments of rebaudioside E was achieved by the extensive 1D and 2D NMR
(
1H and 13C, COSY, HMQC, HMBC) as well as mass spectral data. Further, hydrolysis studies were performed on rebaudioside E using
acid and enzymatic studies to identify aglycone and sugar residues in its structure.
Key words: stevia rebaudiana, compositae, asteraceae, rebaudioside A, spectral data, chemical studies.
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