3-({3-[2-(4-Cyano-phenylamino)-acetylamino]-4-methylamino-benzoyl}-phenyl-amino)-propionic acid methyl ester → 3-({2-[(4-Cyano-phenylamino)-methyl]-1-methyl-1H-benzoimidazole-5-carbonyl}-phenyl-amino)-propionic acid methyl ester

Participants

Reaction Steps

A solution of the product of 1c (22.6 mmol) in 100 mL concentrated acetic acid was heated to reflux for one hour. The solution was then evaporated to dryness, the remaining solid triturated with water and under stirring the pH was adjusted to about 8-9. The crude product was isolated through extraction with ethyl acetate and purified by chromatography on silica gel (eluent: dichloromethane/ethanol 1:1).

Provenance & Evidence