479553-01-0

344327-11-3

479553-01-0

General procedure for the synthesis of 7-azaindole-4-carboxylic acid from 4-cyano-7-azaindole: A mixture of 4-cyano-7-azaindole (11.5 g, 80 mmol), sodium hydroxide (32 g, 800 mmol), water (100 mL) and ethanol (100 mL) was heated to reflux. After 6 hours of reaction, the reaction mixture was cooled to room temperature, neutralized and acidified with concentrated hydrochloric acid. The precipitated solid was collected by filtration to afford 7-azaindole-4-carboxylic acid (10.4 g, 80% yield), which was used in subsequent reactions without further purification.