反应详情

1-Isocyanato-1-methoxycarbonyl-2-phenylethane (1.2 g.) was added to a stirred solution of ethyl 6-amino-4-hydroxycinnolin-3-yl carboxylate (1.17 g.) in pyridine (20 ml.). The mixture was stirred overnight and the solid which separated was washed successively with pyridine (10 ml.) and ether (100 ml.). The solid was dissolved in boiling ethanol (1 l.), and the solution was filtered whilst hot. The filtrate was evaporated to approximately 300 ml. After standing at 0° C. overnight, the mixture was filtered and the solid residue washed successively with ethanol (50 ml.) and ether (100 ml.) to give ethyl 4-hydroxy-6-[3-(α-methoxycarbonylphenethyl)ureido]cinnolin-3-yl carboxylate, m.p. 242°-243° C.

1. customthe solid which separated
2. washwas washed successively with pyridine (10 ml.) and ether (100 ml.)
3. dissolutionThe solid was dissolved
4. filtrationthe solution was filtered whilst hot
5. customThe filtrate was evaporated to approximately 300 ml
6. waitAfter standing at 0° C. overnight
7. filtrationthe mixture was filtered
8. washthe solid residue washed successively with ethanol (50 ml.) and ether (100 ml.)