反应详情

To the suspension of NaH, 60% (1.3 eq, 130 mg) in 600 μl of dry 1,2-dimethoxyethane, under argon atmosphere was carefully added, via syringe, a solution of 3-(2-Methyl-pyrimidin-5-yl)-propionic acid methyl ester (450 mg, 2.5 mmol, 1 eq) and methyl formate (4 eq, 616 μl) in 3 ml of dry 1,2-dimethoxyethane. The resulting suspension was stirred overnight (16 hours) at room temperature. In the reaction mixture was then added 3 ml of dry diethyl ether. The resulting precipitate was collected; it was washed with 3 ml of diethyl ether and dried. It was dissolved in 4 ml of absolute ethanol, thiourea (1.5 eq, 285 mg) was added and the reaction mixture was stirred at reflux under argon atmosphere for 8 hours. Solvent was then evaporated, the rest was dissolved in 3 ml of water and pH value of the solution was adjusted to 4.5-5 using 3N HCl water solution. The resulting precipitate was collected, it was washed with water and dried to afford 5-(2-Methyl-pyrimidin-5-ylmethyl)-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one (210 mg, yield=35.9%, purity=95%) in form of white powder. MS: [M+H]+=235.17 1H NMR (300 MHz; DMSO-d6) δ/ppm 2.54 (s, 3H), 3.50 (s, 2H), 7.48 (s, 1H), 8.55 (s, 2H), 12.38 (br.s., 2H)

1. additionunder argon atmosphere was carefully added, via syringe
2. customThe resulting precipitate was collected
3. washit was washed with 3 ml of diethyl ether
4. customdried
5. dissolutionIt was dissolved in 4 ml of absolute ethanol
6. stirringthe reaction mixture was stirred
7. temperatureat reflux under argon atmosphere for 8 hours
8. customSolvent was then evaporated
9. dissolutionthe rest was dissolved in 3 ml of water
10. customThe resulting precipitate was collected
11. washit was washed with water
12. customdried