Ishii, Hisashi published the artcileFischer indolization and its related compounds. VI. Effect of reagents and substituent of the o-substituted phenylhydrazone on abnormal Fischer indolization, COA of Formula: C12H13NO3, the publication is Chemical & Pharmaceutical Bulletin (1973), 21(7), 1495-505, database is CAplus.
Treatment of Et pyruvate 2-methoxyphenylhydrazone (I) with Lewis acid gave 5-substituted and/or 5-methoxyindoles with Et 7-methoxy-indole-2-carboxylate as the main product in contrast with the abnormal Fischer indolization of I. Differences of the acid strength of the reagent and of the electron d. on a benzene ring due to introduction of some other addnl. substituents was the determinant for the abnormal transformation.
Chemical & Pharmaceutical Bulletin published new progress about 20538-12-9. 20538-12-9 belongs to indole-building-block, auxiliary class Indole,Ester,Ether, name is Ethyl 7-methoxy-1H-indole-2-carboxylate, and the molecular formula is C12H13NO3, COA of Formula: C12H13NO3.
Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles