Nuclear magnetic resonance studies in the interaction of M²⁺ (M = Zn, Cd, Hg and Pb) with adenine

Abstract

The interaction of metal chlorides with adenine in dimethyl sulphoxide (Me₂SO) has been shown to decrease in the order Hg > Zn Cd > Pb. It has been shown that HgCl₂ forms a 1 : 1 complex with adenine with a formation constant of 11.11. mol^-1 at 34.5° which is similar to that reported previously for the nucleoside, adenosine. The addition of chloride ion to adenine solutions containing these metals reverses the chemical shifts markedly and is probably due to [MCl₄]^2- formation. This may be relevant to the absorption of metal ions by living organisms.