反应详情

1.5 g of levofloxacin crude and 10 mg of sodium metabisulfite were put in suspension in 6 ml of a mixture n-BuOH:H2O (9:1) under nitrogen atmosphere. The mixture was heated to reflux temperature until complete dissolution of the material. Then the solution was cooled to RT over a period of 1.5 hours. The precipitate was filtrated under vacuum, washed with a mixture n-BuOH:H2O (9:1) (4 ml) and dried at 60° C. in a vacuum oven to give 1.2 g (81%) of purified levofloxacin hemihydrate. The purified levofloxacin hemihydrate contained virtually no N-oxide levofloxacin.

1. temperatureThe mixture was heated
2. temperatureto reflux temperature
3. dissolutionuntil complete dissolution of the material
4. filtrationThe precipitate was filtrated under vacuum
5. washwashed with a mixture n-BuOH:H2O (9:1) (4 ml)
6. customdried at 60° C. in a vacuum oven