反应详情

The preparation is carried out as in Example 7, from 3 g of 8-amino-5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazine-4-one and 2 times 2.8 ml of ethyl 2-isocyanatoacetate in 170 ml of dimethylformamide. The insoluble material thus obtained is filtered and recrystallized from dimethylformamide. After filtration, washing with water and drying under reduced pressure (1 mm Hg, 0.13 kPa) at 60° C., there are obtained 2.6 g of 8-(3-ethoxycarbonylmethylureido)-5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazine-4-one in the form of a pink solid, the melting point of which is greater than 260° C. (Analysis C18H17N5 O4.0.75H2O.0.20DMF, % calculated C: 58.85, H: 4.66, N: 19.06, % found C: 58.9, H: 5.0, N: 18.9).

1. customThe insoluble material thus obtained
2. filtrationis filtered
3. customrecrystallized from dimethylformamide
4. filtrationAfter filtration
5. washwashing with water
6. customdrying under reduced pressure (1 mm Hg, 0.13 kPa) at 60° C.