Trichloroacetic Acid → 2-(1-Trichloroacetyloxy-4-methyl-3-pentenyl)-5,8-dihydroxy-1,4-naphthoquinone

関与物質

反応手順

288 mg (1 mmole) of shikonin, 226 mg (1.1 mmole) of dicyclohexylcarbodiimide and 30 mg (0.25 mmole) of 4-dimethylaminopyridine were dissolved in 3 ml of dry dichloromethane. To the resulting solution was added 163 mg (1 mmole) of trichloroacetic acid at 0° C. under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 398 mg (Yield: 92%) of the title compound having the following structure as a red precipitate.

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