1-methyl-1H-1,3-benzodiazole-2-carbaldehyde → (+/-)-6-[1-Hydroxy-1-(1-methyl-1H-benzimidazol-2-yl)methyl]-3-methyl-1-(2-methylpropyl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione

Participants

Reaction Steps

A solution of lithium diisopropylamide (3.15 mmol) in anhydrous tetrahydrofuran (5 ml) was added to a solution of 3-methyl-1-(2-methylpropyl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione (500 mg) in anhydrous tetrahydrofuran (20 ml) at −78° C. After 10 minutes, 1-methylbenzimidazole-2-carboxaldehyde (600 mg) was added and the resultant solution kept at −78° C. for 1 hour. The reaction mixture was allowed to warm to ambient temperature and quenched with saturated sodium hydrogen carbonate solution. The mixture was extracted with ethyl acetate and washed with saturated sodium hydrogen carbonate and then brine, then dried over a mixture of magnesium sulfate and silica, filtered, and evaporated. Purification by HPLC over silica eluting with an isohexane:ethyl acetate gradient (4:1 to 0:1) gave the title compound (0.13 g).

Provenance & Evidence