Sodium Sulfate → 6-(4-{[4-(7-Methoxy-2-oxoquinoxalin-1(2H)-yl)butyl]amino}-2-oxopyrrolidin-1-yl)-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-one

Participants

Reaction Steps

6-(4-Amino-2-oxopyrrolidin-1-yl)-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-one (Reference Examples 19; 67 mg, 0.250 mmol) and 4-(7-methoxy-2-oxoquinoxalin-1(2H)-yl)butanal (Reference Examples 3; 58 mg, 0.250 mmol) were dissolved in N,N-dimethylformamide (4 ml). Sodium sulfate (800 mg) was added to this solution and the mixture was stirred at room temperature for 8 hours. Sodium triacetoxyborohydride (80 mg, 0.375 mmol) was added to the reaction solution and the mixture was stirred overnight at room temperature. After completion of the reaction, the reaction solution was diluted with dichloromethane, a saturated sodium hydrogen carbonate aqueous solution was added thereto and the mixture was stirred for 10 minutes. The organic layer was separated, washed sequentially with water (3×) and saturated sodium chloride solution, dried over anhydrous magnesium sulfate and the solvent was removed under reduced pressure. The obtained residue was purified by silica gel column chromatography (chloroform/methanol) to yield 93 mg (76%) of the title compound in the form of a yellow solid.

Provenance & Evidence