1-Pentanesulfonamide → 1-(Isoquinolin-3-ylmethyl)-2-methyl-6-(1-pentane-sulfonylcarbamoyl)benzimidazole

Participants

Reaction Steps

N,N′-carbonyldiimidazole (0.324 g) was added to a solution of 6-carboxy-1-(isoquinolin-3-ylmethyl)-2-methylbenzimidazole (0.413 g) as obtained in Production Example 5 in N,N-dimethylformamide (10 ml) all at once and the mixture was stirred at room temperature for 1.5 hour. Then, 1-pentanesulfonamide (0.302 g) and diazabicyclo-undecene (0.304 g) were added thereto, and the resulting mixture was stirred at 100° C. for 6.5 hour. The reaction solution was concentrated, brine was added to the concentrate, and the mixture was extracted with chloroform. The organic layer was concentrated and the residue was purified by silica gel column chromatography (eluate: methanol/chloroform=1/19) followed by recrystallization from hexane/ethyl acetate (2/3) to yield the desired compound, 1-(isoquinolin-3-ylmethyl)-2-methyl-6-(1-pentanesulfonyl-carbamoyl)benzimidazole (13) (0.142 g).

Provenance & Evidence