Uracil → HCID 69094268, compound

Participants

Reaction Steps

Bis(trimethylsilyl)acetamide (BSA; 29.2 mL, 118 mmol) was added to a mixture of 6 (14.0 g, 23.1 mmol) and uracil (5.99 g, 53.4 mmol) in anhydrous acetonitrile (300 mL). The reaction mixture was refluxed for 1 hour and the clear solution was allowed to cool down to room temperature. Tinchloride (11.55 mL, 99 mmol) was added dropwise at room temperature and the mixture was further stirred for 1 hour. The mixture was then stirred at reflux for 1.5 hour and again cooled to room temperature. Ethyl acetate (250 mL) was added, followed by saturated aqueous NaHCO3 (250 mL) and the mixture was stirred for 15 minutes. After filtration through Celite, the organic layer was separated and washed with saturated aqueous NaHCO3 (250 mL). The combined aqueous layer was extracted with ethyl acetate (250 mL) and the combined organic layer was dried (MgSO4), filtered and evaporated to dryness under reduced pressure. The resulting yellow oil was dissolved in methanol and 25% sodium methanolate (25 mL) was added. Stirring continued overnight. More 25% sodium methanolate (15 mL) was added and stirring was continued overnight. Acetic acid (30 mL) was added and the solvent was removed. The residue was purified by column chromato-graphy with heptane/ethyl acetate 50:50 to 100% ethyl acetate. Intermediate 7 (9.38 g, 76%) was obtained as a colorless oil. HPLC Condition A, Rt: 2.49 min, m/z=465 (M+H)+. 1H NMR (400 MHz, CDCl3) δ ppm 8.39 (1H, NH), 7.75 (d, 1H, J=8.0 Hz), 7.22-7.43 (m, 10H), 6.05 (s, 1H), 5.71-5.84 (m, 1H), 5.35 (d, 1H, J=8.0 Hz), 5.00-5.11 (m, 2H), 4.70 (d, 1H, J=11.5 Hz), 4.53 (d, 1H, J=11.5 Hz), 4.47 (d, 1H, J=11.1 Hz), 4.47 (d, 1H, J=11.1 Hz), 4.11-4.16 (m, 1H), 4.04 (d, 1H, J=8.0 Hz), 3.81-3.87 (m, 1H), 3.45-3.52 (m, 1H), 3.17 (bs, OH), 2.15-2.33 (m, 2H).

Provenance & Evidence