Citric Acid → HCID 50996222, compound

Participants

Reaction Conditions

Reaction Steps

To a mixed solvent solution of (3S)-7-chloro-1-{1-[(3-fluoro-2′-{[(2R)-3-hydroxy-2-methylpropyl]oxy}biphenyl-4-yl)carbonyl]piperidin-4-yl}-3-methyl-1H-pyrido[2,3-b][1,4]oxazin-2(3H)-one (920 mg) in acetonitrile (10 ml) and a neutral phosphate pH standard solution (pH 6.86) (8 ml) were added at room temperature 2,2,6,6-tetramethyl-1-piperidyloxy radical (25.3 mg), 79% sodium chlorite (371 mg) and a 5% aqueous sodium hypochlorite solution (0.041 ml). After the reaction solution was stirred at 50° C. overnight, 2,2,6,6-tetramethyl-1-piperidyloxy radical (25.3 mg) and a 5% aqueous sodium hypochlorite solution (0.041 ml) were added, and further stirred for 4 hours. The reaction solution was brought back to room temperature, and an aqueous sodium sulfite solution and a 10% aqueous citric acid solution were added, and extracted with dichloromethane. The organic layer was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography to afford (2S)-3-{[4′-({4-[(3S)-7-chloro-3-methyl-2-oxo-2,3-dihydro-1H-pyrido[2,3-b][1,4]oxazin-1-yl]piperidin-1-yl}carbonyl)-3′-fluorobiphenyl-2-yl]oxy}-2-methylpropanoic acid (701 mg).

Provenance & Evidence