Hydrochloric Acid → K-604

Participants

Reaction Steps

Acetonitrile (450 mL) and potassium carbonate (85.7 g, 0.62 mol) were added to 1-[2-(benzimidazol-2-ylthio)ethyl]piperazine.3 hydrochloride (59.42 g, 0.16 mol) in water (180 mL). Subsequently, 2-bromo-N-[2,4-bis(methylthio)-6-methylpyridin-3-yl]acetamide (48.19 g, 0.15 mol) was gradually added thereto, and the resultant mixture was stirred at room temperature for 2 hours. The reaction mixture was diluted with water (300 mL), followed by stirring for 1 hour. The crystals that precipitated were separated through filtration, followed by washing with a solvent mixture (600 mL) of acetonitrile and water (1:1), washing with water (200 mL), and drying through air blow at 40 to 50° C., to thereby yield 2-[4-[2-(benzimidazol-2-ylthio)ethyl]piperazin-1-yl]-N-[2,4-bis(methylthio)-6-methylpyridin-3-yl]acetamide as colorless crystals (75 g, yield: 99%).

Provenance & Evidence