1-Methoxyindole-3-carboxylic acid (compound 5) is synthetic from a phytoalexin nucleophilic substitution reaction selectively at the 2-position[1].
References
[1] M. Somei, et al. Syntheses of Wasabi Phytoalexin (Methyl 1-Methoxyindole-3-carboxylate) and Its 5-Iodo Derivative, and Their Nucleophilic Substitution Reactions. HETEROCYCLES. 2001, 54, 1.
