反应详情

A mixture of a sodium ethylate solution prepared from 6.76 g of metallic sodium and 290 ml of anhydrous ethanol, 35 g of 2-(3-methyl-xanthine-7-yl)-acetamidoxime and 43.0 g of ethyl acetate is heated to boiling under stirring for 4 hours. The hot reaction mixture is filtered, the filtrate is evaporated in vacuo and the residue is dissolved in 200 ml of water. The pH of the solution is adjusted to 7 by adding 10% hydrochloric acid, the precipitate is filtered by suction and crystallized twice from water. Thus, 18.0 g of 3,7-dihydro-3-methyl-7-([5-methyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione are obtained, m.p.: 262°-264° C.

1. temperatureis heated
2. filtrationThe hot reaction mixture is filtered
3. customthe filtrate is evaporated in vacuo
4. dissolutionthe residue is dissolved in 200 ml of water
5. additionby adding 10% hydrochloric acid
6. filtrationthe precipitate is filtered by suction
7. customcrystallized twice from water