反应详情

To crude ethyl (6-methylamino-2,4-dioxo-1,3-diphenyl-1,2,3,4-tetrahydro-pyrimidine-5-thiocarbonyl)-carbamate 23 (1.58 g) obtained in Step 4 was added N,N-dimethylformamide (8.4 ml), triethylamine (0.63 ml) was added under a nitrogen atmosphere, and the mixture was stirred at room temperature for 30 min. Water (25 ml) was added, the mixture was stirred, 1N hydrochloric acid (5.0 ml) was added, and the mixture was stirred at room temperature for 1 hr. The crystals were collected by filtration, washed with water and dried to give crude 5-mercapto-8-methyl-1,3-diphenyl-1H,8H-pyrimido[4,5-d]pyrimidine-2,4,7-trione 24 (1.53 g, over weight) as yellow crystals, which were used for the next step without purification.

1. additionwas added under a nitrogen atmosphere
2. stirringthe mixture was stirred
3. stirringthe mixture was stirred at room temperature for 1 hr
4. filtrationThe crystals were collected by filtration
5. washwashed with water
6. customdried