反应详情

A mixture of 5,6-diamino-3-methyl-1-phenyl-2,4 (1H, 3H) -pyrimidinedione (3.02 g, 13 mmol), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (3.58 g, 14.3 mmol) and 4-(dimethylamino)pyridine (0.32 g, 2.6 mmol) was suspended in dichloromethane (60 mL). To the resultant suspension was added dropwise a solution of N, N'-dicyclohexylcarbodiimide (2.82 g, 13.7 mmol) indichloromethane (60 mL) at room temperature. The reaction mixture was stirred overnight and then filtered. The filtrate was concentrated and then subjected to silica-gel column chromatography, thereby giving the title compound (yield 57%). TOF-MS (Time-of-flight type mass spectrum): m/z 465 [M+H]+1H-NMR (CDC13):δ1.60(3H, s), 1.90-2.04(1H, m), 2.08(3H, s), 2.18(3H, s), 2.29(3H, s), 2.30-2.38(1H, m), 2.54-2.64(2H, m), 3.34(3H, s), 4.32(1H, s), 5.17(2H, bs), 7.27-7.36(2H, m), 7.53-7.60 (3H, m), 8.41 (1H, bs)

1. filtrationfiltered
2. concentrationThe filtrate was concentrated