Sulfuric Acid → HCID 19434887, compound

Participants

Reaction Conditions

Reaction Steps

10 mL of concentrated sulfuric acid was added to 1.00 g (1.98 mmol) of 6,8-difluoro-2-(3-fluoro-4-pivaloylaminophenyl)-7-hydroxymethyl-5-pivaloylamino-4H-1-benzopyran-4-one obtained in Example 118 (4) and the mixture was stirred at 50° C. for 20 minutes. The reaction solution was cooled on ice, ice water was added and the precipitated crystals were collected by filtration. The crystals were purified by silica gel column chromatography (chloroform:methanol=9:1-chloroform:methanol:aqueous ammonia=40:10:1) and triturated with ethanol to give 293 mg of Compound 119 (yield: 36%).

Provenance & Evidence