The molecule is a monocarboxylic acid anion resulting from the deprotonation of the carboxy group of steviolmonoside. The major species at pH 7.3. It is a conjugate base of a steviolmonoside.
(1R,4S,5R,9S,10R,13S)-5,9-dimethyl-14-methylidene-13-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxytetracyclo[11.2.1.01,10.04,9]hexadecane-5-carboxylate