Isonicotinic Acid → isonicotinic acid 3-(1-methyl-1H-indol-3-yl)-4-(1-methyl-6-nitro-1H-indol-3-yl)-2,5-dioxo-2,5-dihydro-pyrrol-1-ylmethyl ester

Participants

Reaction Steps

To a solution of dimethylaminopyridine (1.5 equivalents) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.5 equivalent) in CH2Cl2 was added 4-picolinic acid (1.2 equivalents) and the reaction mixture was stirred a few minutes. 1-Hydroxymethyl-3-(1-methyl-1H-indol-3-yl)-4-(1-methyl-6-nitro-1H-indol-3-yl)-pyrrole-2,5-dione, prepared as in example 1a, was added and the reaction mixture was stirred at room temperature for several hours. The mixture was diluted with dichloromethane, washed with aqueous HCL, saturated NaHCO3, water, dried over MgSO4 and evaporated. The residue was purified by column chromatography to afford isonicotinic acid 3-(1-methyl-1H-indol-3-yl)-4-(1-methyl-6-nitro-1H-indol-3-yl)-2,5-dioxo-2,5-dihydro-pyrrol-1-ylmethyl ester (yield—76%).

Provenance & Evidence