Sodium Bicarbonate → 6-(((1-(2-(7-methoxy-2-oxoquinoxaline-1-(2H)-yl)ethyl)piperidin-4-yl)amino)methyl)-2H-1,4-benzooxazine-3(4H)-one

Participants

Reaction Steps

To 3.0 mL of a methanol solution containing 0.20 g of 1-(2-(4-aminopiperidin-1-yl)ethyl)-7-methoxyquinoxalin-2(1H)-one, 0.12 g of 3-oxo-3,4-dihydro-2H-1,4-benzooxazine-6-carbaldehyde, 38 μL of acetic acid and 83 mg of sodium cyanoborohydride were added at room temperature and stirred at the same temperature for 6.5 hours. To the reaction mixture, chloroform and aqueous saturated sodium hydrogen carbonate solution were added to be adjusted to pH 10.2, the organic layer was separated, and the aqueous layer was extracted with chloroform. The organic layer and extracts were combined, washed sequentially with water and aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [eluent; chloroform:methanol=5:1], diethyl ether was added to the foam thus obtained, and the resulting solid was filtered to afford a yellow solid. To this solid, ethyl acetate and chloroform were added, the mixture was cooled to the room temperature after heating, and the resulting solid was filtered to give 59 mg of 6-(((1-(2-(7-methoxy-2-oxoquinoxaline-1-(2H)-yl)ethyl)piperidin-4-yl)amino)methyl)-2H-1,4-benzooxazine-3(4H)-one a pale yellow solid.

Provenance & Evidence