Diketene → HCID 69733596, compound

Participants

Reaction Steps

A mixture of (R)-3-(5-acetoxyhexyl)-6-amino-1-methyluracil (500 mg, 1.77 mmol), 1,2-dichloroethane (5 ml) and diketene (0.14 ml, 1.77 mmol) was heated at reflux for 18 hours. Another portion of diketene (0.2 ml) was added and the mixture was heated at reflux for an additional 18 hours. After cooling to room temperature, the mixture was concentrated under reduced pressure. The residue was purified by column chromatography on silica gel eluting with ethyl acetate-hexane (1:1) to provide (R)-3-(5-acetoxyhexyl)-1,7-dimethylpyrido[2,3-d]pyrimidine-2,4,5(1H,3H,8H)-trione (300 mg, 49% yield) as an oil. 1H NMR (300 MHz, CDCl3) δ 1.20 (d, 3H), 1.25-1.71 (m, 6H), 2.00 (s, 3H), 2.46 (s, 3H), 3.62 (s, 3H), 4.00 (t, 2H), 4.86 (sextet, 1H), 6.49 (s, 1H), 12.15 (s, 1H). 13C NMR (75 MHz, CDCl3) δ 19.64, 20.96, 22.46, 25.02, 27.19, 29.15, 35.19, 40.67, 70.29, 94.48, 105.71, 150.09, 150.73, 164.92, 165.18, 167.82, 170.15.

Provenance & Evidence