The molecule is a monocarboxylic acid anion that is the conjugate base of 3,4-dimethylindole-2-carboxylic acid, obtained by deprotonation of the carboxy group. It is a conjugate base of a 3,4-dimethylindole-2-carboxylic acid.
3,4-dimethyl-1H-indole-2-carboxylate