摘要:
The reactions of ethyl 3-amino-4-carbamoyl-5-methylthiophene-2-carboxylate with 1,3-dicarbonyl compounds were studied. During the reactions, the corresponding ketone is eliminated to give ethyl 5-methyl-4-oxo-3,4-dihydrothieno[3,4-d]pyrimidine-7-carboxylates.