反应详情

A mixture of 9-hydroxy-7-isopropyl-2-(2-propenyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,6,8(7H)-trione (3.0 g, 11 mmol) and rhodium trichloride hydrate (200 mg, 1 mmol) in EtOH (75 mL) was heated to reflux for 8 h. The reaction was cooled to ambient temperature and the solvent was removed in vacuo. The reddish solid was triturated in MeOH and collected by filtration to give the title compound as a solid. HPLC RT=2.90 min (Method A); ES MS (M+H)=280; 1H NMR (400 MHz, DMSO-d6) δ 11.59 (s, 1H), 7.10 (d, J=4.5 Hz, 1H), 5.49 (sextet, J=6 Hz, 1H), 5.04 (septet, J=7 Hz, 1H), 3.97 (m, 2H), 3.79 (m, 2H), 1.76 (d, J=6 Hz, 3H), 1.39 (d, J=7 Hz, 6H).

1. temperaturewas heated
2. temperatureto reflux for 8 h
3. customthe solvent was removed in vacuo
4. customThe reddish solid was triturated in MeOH
5. filtrationcollected by filtration