Reaction of the purine and pyrimidine derivatives with the electrode mercury

Abstract

Summary The electrochemical behaviour of 30 purine and pyrimidine derivatives and of a further 12 derivatives containing sulphur or halogens was studied. It was demonstrated that most of these substances react with the electrode mercury and form sparingly soluble compounds; this phenomenon can be exploited for the determination of purine and pyrimidine derivatives at low concentrations. The relation between the structural formulae of the substances and their ability to yield anodic polarographic currents conditioned by formation of sparingly soluble compounds with mercury was found. The behaviour of adenine and 8-oxyadenine was studied in greater detail by means of differential (DPP) and normal pulse polarography (NPP), d.c. polarography and cathodic stripping voltammetry (CSV). Both substances can be determined with the aid of CSV at concentrations of the order of magnitude of 10−9 M, while DPP may be used at concentrations three to four orders of magnitude higher. Interactions of some purine and pyrimidine derivatives with Hg(II) ions in homogeneous aqueous solutions were investigated. On the one hand, a correlation was found between the ability of these substances to react with mercury in solution and form precipitates, and, on the other hand, to yield anodic polarographic currents.