Hydrochloric Acid → 9-hydroxy-2-isopropyl-6-(1-phenyl-cyclohexylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione

Participants

Reaction Steps

To the stirred solution of 9-benzyloxy-2-isopropyl-6-(1-phenyl-cyclohexylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione (259) (0.18 g, 0.37 mmol) in methanol (5.0 mL) was added concentrated HCl (5.0 mL) and the reaction mixture was stirred at room temperature for 3 h. After completion of the reaction, the solvent was reduced and the crude product was extracted with 10% methanol in dichloromethane. The organic part was washed with saturated NaHCO3 solution, separated and dried over Na2SO4. After evaporation, the crude product was purified by nor mal silica gel column chromatography (using 3% methanol in dichloromethane) to get 9-hydroxy-2-isopropyl-6-(1-phenyl-cyclohexylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione (260) (70.0 mg, 48.0%) as a white solid.

Provenance & Evidence