反应详情

A mixture of 9(R)-bromoacetyl-6,9,11-trihydroxy-5,7,8,9,10,12-hexahydronaphthacene-5,12-dione (1.00 g) obtained in Reference Example 4-(1), sodium valerate (1.44 g) and acetone (50 ml) was stirred under reflux for 2 hours. After removing insoluble matters by filtration, the reaction mixture was concentrated under reduced pressure. The residue was treated with ether (15 ml) and precipitated crystals were collected by filtration to give orange crystals of 9(R)-valeryloxyacetyl-6,9,11-trihydroxy-5,7,8,9,10,12-hexahydronaphthacene-5,12-dione. M.P., 149°-152° C.

1. temperatureunder reflux for 2 hours
2. customAfter removing insoluble matters
3. filtrationby filtration
4. concentrationthe reaction mixture was concentrated under reduced pressure
5. additionThe residue was treated with ether (15 ml)
6. customprecipitated crystals
7. filtrationwere collected by filtration