反应详情

102.6 g of (+)-2-[4-[((3S)-1-acetimidoyl-3-pyrrolidinyl)oxy]phenyl]-3-(7-amidino-2-naphthyl)propionic acid dihydrochloride was dissolved in 1,000 ml of water. With stirring, the thus prepared solution was adjusted to pH 4.8 by gradually adding a strongly basic OH type ion exchange resin (Amberlite IRA-410). Thereafter, the resin was removed by filtration, and the resulting filtrate was concentrated to dryness. The thus obtained residue (94.6 g) was dissolved in 142 ml of water, and the solution was mixed with 1,570 ml of ethanol, and stirred at room temperature for 1 hour. After removing thus formed crystals by filtration, the resulting mother liquor was seeded with the crystals of interest, and stirred at 8° C. for 40 hours. Thereafter, the thus precipitated crystals were collected by suction filtration, washed with ethanol, and then air-dried for 6.5 hours under normal pressure at a relative humidity of 60 to 70%. In this way, 70.3 g of the title compound was obtained in the form of colorless prism crystals.

1. additionby gradually adding a strongly basic OH type ion exchange resin (Amberlite IRA-410)
2. customThereafter, the resin was removed by filtration
3. concentrationthe resulting filtrate was concentrated to dryness
4. dissolutionThe thus obtained residue (94.6 g) was dissolved in 142 ml of water
5. additionthe solution was mixed with 1,570 ml of ethanol
6. stirringstirred at room temperature for 1 hour
7. customAfter removing thus formed crystals
8. filtrationby filtration
9. stirringstirred at 8° C. for 40 hours
10. filtrationThereafter, the thus precipitated crystals were collected by suction filtration
11. washwashed with ethanol
12. customair-dried for 6.5 hours under normal pressure at a relative humidity of 60 to 70%