117977-21-6

118175-10-3

134469-07-1

117977-21-6

General procedure for the synthesis of 2-[[[4-(3-methoxypropoxy)-3-methylpyrimidin-2-yl]methyl]thio]-1H-benzimidazole from 2-hydroxymethyl-4-(3-methoxypropoxy)-3-methylpyridine and 1H-benzo[d]imidazole-2-thiol: 100 g of 2-hydroxymethyl-4-(3-methoxypropoxy)-3-methylpyridine ( 473.35 mmol) in a 2L three-necked flask, 1 L of tetrahydrofuran was added as solvent, followed by 71.10 g of 1H-benzo[d]imidazole-2-thiol (473.35 mmol) and 136.58 g of triphenylphosphine (520.69 mmol). Stirring was turned on and the reaction temperature was controlled at 0 °C. Slowly 90.678 g of diethyl azodicarboxylate (520.69 mmol) was added dropwise. After the dropwise addition, the reaction was maintained for 5h to 10h, during which the reaction progress was monitored by TLC. Upon completion of the reaction, the tetrahydrofuran was evaporated to dryness by rotary evaporator, and the resulting crude product was purified by recrystallization from methanol to give 130.0 g of the target product 2-[[[4-(3-methoxypropoxy)-3-methylpyrimidin-2-yl]methyl]thio]-1H-benzimidazole in 80% yield.