Ethanolamine → HCID 484063, 화합물

1-(5-Amino-2,4-difluorophenyl)-6,7-difluoro-8-methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (500 mg), monoethanolamine (410 mg) and N-methylpyrrolidine (170 mg) were added to pyridine (1,500 mg), and the mixture was stirred at 90° C. for 71 hours. The reaction mixture was concentrated under reduced pressure. A process of adding ethanol (1.5 ml) to the residue and then concentrating the mixture under reduced pressure was conducted 3 times repeatedly. The resultant residue was subjected to column chromatography (silica gel: 15 g, eluent; chloroform:methanol=50:1→10:1). Ethanol (0.5 ml) was added to a concentrate of a fraction containing a main product, and the mixture was stirred at room temperature. Deposits formed were collected by filtration and washed with ethanol and diisopropyl ether in that order to obtain the title compound (62 mg) as a brown powder.