反应详情

Methyl 7-[[(7R)-8-cyclopentyl-7-ethyl-5-methyl-6-oxo-7H-pteridin-2-yl]amino]-2,3-dihydrobenzofuran-4-carboxylate 1p (5 g, 11 mmol) was dissolved in 180 mL mixture solution of 1 mol/L lithium hydroxide solution and methanol (V/V=1:1). The resulting mixture was heated to reflux for 3 hours with stirring. The reaction solution was added with 50 mL of water, concentrated under reduced pressure and extracted with ethyl acetate (50 mL×3). 1 M hydrochloric acid was added dropwise to adjust the aqueous phase pH to 2 resulting in the formation of precipitate. The precipitate was filtered, and dried to obtain the title compound 7-[[(7R)-8-cyclopentyl-7-ethyl-5-methyl-6-oxo-7H-pteridin-2-yl]amino]-2,3-dihydrobenzofuran-4-carboxylic acid 1q (4.70 g, yield: 97.0%) as a white solid.

1. temperatureThe resulting mixture was heated
2. temperatureto reflux for 3 hours
3. concentrationconcentrated under reduced pressure
4. extractionextracted with ethyl acetate (50 mL×3)
5. addition1 M hydrochloric acid was added dropwise
6. filtrationThe precipitate was filtered
7. customdried