反应详情

To the compound (3.00 g) obtained in Example 31 and pyridine (25 ml) was gradually added dropwise acetic anhydride (2.1 ml) under ice-cooling. The mixture was stirred at 0° C.-room temperature for 66 hours and the resulting crystals were collected by filtration. The crystals were washed with hexane-ethyl acetate and dried to give 2.98 g of white powdery crystals (yield 80%).

1. temperaturecooling
2. filtrationthe resulting crystals were collected by filtration
3. washThe crystals were washed with hexane-ethyl acetate
4. customdried