反应详情

2.64 g of formic acid/acetic acid anhydride are dripped, while cooling, into a suspension of 2.9 g of 2,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine (trimethoprim) in 35 ml of pyridine and reacted at 50° to 60° C. for two hours. The reaction mixture is then poured into 400 ml of water and the precipitate is filtered off and recrystallized from a mixture of dimethylformamide and water. 2.4 g (75% of theory) of 4-amino-2-formamido-5-(3,4,5-trimethoxybenzyl)-pyrimidine of melting point 240° to 242° C. are obtained.

1. customreacted at 50° to 60° C. for two hours
2. filtrationthe precipitate is filtered off
3. customrecrystallized from a mixture of dimethylformamide and water