Water → (+)-(1R,3R)-1-(3-hydroxy-cyclopentyl)-3-(4-methoxy-phenyl)-7-phenylamino-3,4-dihydro-1H-pyrimido[4,5-d]pyrimidin-2-one

Participants

Reaction Steps

(−)-(1R,3R)-1-[3-(tert-Butyl-dimethyl-silanyloxy)-cyclopentyl]-3-(4-methoxy-phenyl)-7-phenylamino-3,4-dihydro-1H-pyrimido[4,5-d]pyrimidin-2-one (148 mg, 0.27 mmol) (from Example 27e supra) was dissolved at 0° C. in a 25% trifluoroacetic acid in dichloromethane solution (5 mL) that contained water (300 μL). After stirring for 30 minutes the reaction mixture was partitioned between ethyl acetate and 0.5 N aqueous sodium hydroxide. The pH of the aqueous layer was adjusted to 12 via the addition of solid sodium hydroxide. The organic layer was then collected, dried over sodium sulfate, filtered and concentrated to give the crude product. Purification by silica gel column chromatography using a 0–100% ethyl acetate in hexanes to 0–40% tetrahydrofuran in ethyl acetate gradient followed by a precipitation out of dichloromethane with excess pentane afforded (+)-(1R,3R)-1-(3-hydroxy-cyclopentyl)-3-(4-methoxy-phenyl)-7-phenylamino-3,4-dihydro-1H-pyrimido[4,5-d]pyrimidin-2-one as a white solid. (Yield 92 mg, 86%).

Provenance & Evidence