Sodium Bicarbonate → 6-(((1-(2-(7-methoxy-2-oxoquinoxalin-1(2H)-yl)ethyl)piperidin-4-yl)amino)methyl)-2H-pyrido(3,2-b)(1,4)thiazin-3(4H)-one

Participants

Reaction Steps

To 2 mL of an N,N-dimethylformamide solution containing 63 mg of 1-(2-(4-aminopiperidin-1-yl)ethyl)-7-methoxyquinoxalin-2(1H)-one hydrochloride, 36 mg of 3-oxo-3,4-dihydro-2H-pyrido(3,2-b)(1,4)thiazine-6-carbaldehyde, 0.14 mL of acetic acid and 0.12 mL of triethylamine were added, and stirred for 3 hours, thereafter 53 mg of sodium triacetoxyborohydride was added, and stirred at room temperature for 45 min. Aqueous saturated sodium hydrogen carbonate solution and ethyl acetate were added, the organic layer was separated, and the aqueous layer was extracted with ethyl acetate. The organic layer and extracts were combined, washed with 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 basic silica gel column chromatography [eluent; chloroform:methanol=10:1], to give 25 mg of 6-(((1-(2-(7-methoxy-2-oxoquinoxalin-1(2H)-yl)ethyl)piperidin-4-yl)amino)methyl)-2H-pyrido(3,2-b)(1,4)thiazin-3(4H)-one as a white solid.

Provenance & Evidence