Polarographic behaviour of 2-(5-nitro-2-furyl)-5-(2-aminoethoxy)- pyrimidine derivatives

Polarographic reduction of the title compounds in mixtures of Britton-Robinson buffers and methanol (1:1) or DMF (3:1) for compound 10 at the pH range of 2.8--11.3 is described. In strongly acid medium the compounds were reduced in two diffusion governed waves corresponding to the consecutive reduction of NO2-group (6-electron wave) and pyrimidine ring (2-electron wave) to amine and dihydropyrimidine, respectively; with increasing pH the second wave became, however, much worse shaped. In alkaline medium a third wave appeared, the limiting current of which corresponded to a 2-electron process; the wave corresponds probably to the further reduction of pyrimidine ring to tetrahydroderivative. Mechanism of the reduction of the title compounds has been suggested and discussed.