Hydrochloric Acid → 1-(2-(6-(2,3-dihydro(1,4)dioxino(2,3-c)pyridin-7-ylmethyl)-7-oxo-2,6-diazabicyclo(3.2.1)oct-2-yl)ethyl)-7-methoxyquinoxalin-2(1H)-one

Participants

Reaction Steps

To 5 mL of a methanol solution containing 60 mg of methyl 4-((2,3-dihydro(1,4)dioxino(2,3-c)pyridin-7-ylmethyl)amino)-1-(2-(7-methoxy-2-oxoquinoxalin-1(2H)-yl)ethyl)piperidine-2-carboxylate, 0.2 mL of 20% aqueous sodium hydroxide solution was added at room temperature, and stirred for 1 hour and 10 min. Further, 0.5 mL of 20% aqueous sodium hydroxide solution was added at room temperature, and stirred at the sane temperature for 1 hour and 50 min. The reaction mixture was adjusted to pH 6.2 with 2 mol/L hydrochloric acid under water-cooling, the solvent was removed under reduced pressure, water, ethyl acetate and diethyl ether were added, and the resulting solid (A′) was filtered. Also, the solvent of the filtrate (B′) was removed under reduced pressure. To the residue thus obtained, water, ethyl acetate and diethyl ether were added, the organic layer was separated, and the solvent was removed under reduced pressure. To the residue thus obtained, hexane and diethyl ether were added, and the resulting solid (B) was filtered to give 9 mg of 1-(2-(6-(2,3-dihydro(1,4)dioxino(2,3-c)pyridin-7-ylmethyl)-7-oxo-2,6-diazabicyclo(3.2.1)oct-2-yl)ethyl)-7-methoxyquinoxalin-2(1H)-one as a pale yellow solid.

Provenance & Evidence