HCID 19434836, compound → HCID 19434817, compound

Participants

Reaction Steps

206 mg (0.398 mmol) of 6,8-difluoro-2-(3-fluoro-4-pivaloylaminophenyl)-7-(1-hydroxyethyl)-5-pivaloylamino-4H-1-benzopyran-4-one obtained in Example 94 (1) was suspended in 20 mL of toluene, 348 mg (3.98 mmol) of manganese dioxide was added and the mixture was heated at reflux for 2 hours. The reaction solution was filtered, the solvent was distilled off under reduced pressure and the residue was purified by silica gel column chromatography (chloroform:acetonitrile=50:1) to give 179 mg of 7-acetyl-6,8-difluoro-2-(3-fluoro-4-pivaloylaminophenyl)-5-pivaloylamino-4H-1-benzopyran-4-one (yield: 87%).

Provenance & Evidence