Abstract

The 3-R-thieno[3,2-d]pyrimidine-2,4(1H,3H)-diones (5a-с) and 3-R-2-thioxo-2,3-dihydrothieno[3,2-d]pyrimidine-4(1H)-ones (5d-g) were
synthesized using methyl 3-aminothiophene-2-carboxylate and alkyl-, arylisocyanates and isothiocyanates respectively, which in turn
converted into its N- и S- alkyl derivates (8a-e, 9a-g). 2-Aminothieno[3,2-d]pyrimidin-4(3H)-one (14a-c, 16) were received as a result the
interaction the methyl 3-aminothiophene-2-carboxylate with benzoyl- and pyrimidin-2-yl cyanamides.

Key words: thiophenes, thienopyrimidinones, 3-R-thieno[3,2-d]pyrimidine-2,4(1H,3H)-dione, 3-R-2-thioxo-2,3-dihydrothieno[3,2- d]pyrimidin-4(1H)-one, 2-aminothieno[3,2-d]pyrimidin-4(3H)-one, alkylation