Hydroquinone → HCID 9861916, compound

Participants

Reaction Steps

A mixture of (R)-6-amino-3-(5-methoxyhexyl)uracil (152 mg, 0.595 mmol), diketene (0.07 ml, 0.89 mmol), hydroquinone (7 mg, 0.06 mmol) and benzene (5 ml) was heated at reflux for 3 hours. Another portion of diketene (0.2 ml) was added and heating at reflux was continued for 18 hours. After cooling to room temperature, the mixture was concentrated under reduced pressure. The residue was partitioned between water (20 ml) and ethyl acetate (20 ml). The organic layer was concentrated under reduced pressure and the residue was purified by column chromatography on silica gel eluting with 20% ethyl acetate-toluene to provide (R)-1,7-dimethyl-3-(5-methoxyhexyl)pyrido[2,3-d]pyrimidine-2,4,5(1H,3H,8H)-trione (101 mg, 53% yield) as an oil which crystallized on standing. 1H NMR (300 MHz, CDCl3) δ 1.13 (d, 3H), 1.30-1.79 (m, 6H), 2.48 (s, 3H), 3.29 (m, 1H), 3.30 (s, 3H), 3.75 (s, 3H), 4.02 (t, 2H), 6.50 (s, 1H), 12.21 (s, 1H).

Provenance & Evidence