Hydrochloric Acid → 9-{3-[2-(Hydroxymethyl)pyrimidin-4-yl]-6-methoxy-2-methylphenyl}-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione

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Reaction Conditions

Reaction Steps

1,1′-Carbonyldiimidazole (33.9 mg, 0.209 mol) was added to a suspension of the 4-[4-methoxy-2-methyl-3-(3,3,6,6-tetramethyl-1,8-dioxo-2,3,4,5,6,7,8,9-octahydro-1H-xanthen-9-yl)phenyl]pyrimidine-2-carboxylic acid obtained in Example 75-4 (90.0 mg, 0.174 mmol) in THF (2.0 mL) at room temperature, and the mixture thus obtained was then stirred at 50° C. for 1.5 hours. Thereafter, DMF (0.5 mL) was added to the resulting solution, and the mixture thus obtained was further stirred at the same temperature as above for 20 minutes. Subsequently, the reaction solution was cooled to 0° C., and sodium borohydride (13.2 mg, 0.348 mmol) and water (0.1 mL) were then added to the reaction solution. The mixture thus obtained was stirred at room temperature for 30 minutes. Thereafter, water and 1 M-hydrochloric acid were added to the reaction solution, and the mixed solution was then extracted with ethyl acetate twice. The organic layer thus obtained was washed with brine, and was then dried over anhydrous sodium sulfate. After that, the solvent was distilled away under reduced pressure. The residue thus obtained was purified by silica gel column chromatography (dichloromethane:methanol=1:0 to 10:1, v/v), and was then solidified with diethyl ether to obtain the title compound (49.9 mg, yield: 56%).

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