A versatile route to potential dihydrofolate reductase inhibitors via the hitherto unknown 6-benzyl-2-(O-methyl)uracils: Synthesis of isotrimethoprim

The synthesis of 2, 4-diamino-6-(3, 4, 5-trimethoxybenzyl)pyrimidine (isotrimethoprim) has been accomplished starting from 2-(O-methyl)-6-(3, 4, 5-trimethoxybenzyl)uracil by standard procedures. The benzyluracil derivative has been obtained by reacting O-methylisourea sulphate and ethyl 3, 4, 5-trimethoxyphenacetylace-tate.