6-Methoxyoxindole → 3-[5-(6-Methoxy-2-oxo-1,2-dihydroindol-3-ylidenemethyl)-4-methyl-1H-pyrrol-3-yl]-propionic acid

Participants

Reaction Steps

4-(2-Carboxyethyl)-2-formyl-3-methylpyrrole (190 mg), 163 mg of 6-methoxy-2-oxindole, and 2 drops of piperidine in 2 mL of ethanol were heated to 90° C. for 3 hours. The reaction mixture was cooled and concentrated. The residue was suspended in 6 N aqueous hydrochloric acid. The precipitate was filtered, washed with water to pH 6 and dried in a vacuum oven to give 140 mg of the title compound (43%) as a brown solid.

Provenance & Evidence