反应详情

2-Amino-4-hydroxy-6-(3-hydroxy-2-hydroxyimino-1-spirocyclohexylpropylamino)-5-nitropyrimidine (II) (500 mg) was dissolved in the minimum of 0.1M sodium hydroxide by warming on the steam bath. Sodium dithionite was added portionwise until an almost colourless solution was obtained. On cooling the dihydropteridine separated and was filtered off and purified by dissolving in 2M HCl and reprecipitated by the addition of 0.88 ammonia to pH8. On standing the dihydropteridine (I) (150 mg; yield 38%) was obtained as a pale yellow crystalline solid, m.p. >300 (decomp.).

1. temperatureby warming on the steam bath
2. customwas obtained
3. customseparated
4. filtrationwas filtered off
5. custompurified
6. dissolutionby dissolving in 2M HCl
7. customreprecipitated by the addition of 0.88 ammonia to pH8