反应详情

A mixture of (3S,4S)-6-(4-tert-butyldimethylsilyloxyphenyl)sulphonyl-3,4-dihydro-3,4-epoxy-2,2,3-trimethyl-2H-benzo[b]pyran (0.71 g) (see Preparation 14), 1,2-dihydro-4-hydroxy-2-methyl-1-oxophthalazine (0.846 g) (see Preparation 21), pyridine (0.4 ml) and 1,4-dioxane (10 ml) was heated under reflux for 4 days. The solvent was removed under reduced pressure, the residue was dissolved in ethyl acetate and washed first with dilute aqueous citric acid solution and then with brine. The organic phase was dried (anhydrous magnesium sulphate), the solvent was removed and the crude product was chromatographed on silica eluting with a solvent gradient of 100:1:0.15 to 180:20:1 dichloromethane: methanol: 35% aqueous ammonia solution to yield (3S,4R)-3,4-dihydro-4-(1,2-dihydro-2-methyl-1-oxophthalazin-4-yl)oxy-3-hydroxy-6-(4-hydroxyphenyl)sulphonyl-2,2,3-trimethyl-2H-benzo[b]pyran (0.12 g) as a solid.

1. temperaturewas heated
2. temperatureunder reflux for 4 days
3. customThe solvent was removed under reduced pressure
4. dissolutionthe residue was dissolved in ethyl acetate
5. washwashed first with dilute aqueous citric acid solution
6. dry with materialThe organic phase was dried (anhydrous magnesium sulphate)
7. customthe solvent was removed
8. customthe crude product was chromatographed on silica eluting with a solvent gradient of 100:1:0.15 to 180:20:1 dichloromethane