Interaction of Dioxovanadium(V) with Alanine, Alanylalanine, and Alanylglycine

The stability constants of the systems dioxovanadium(V) with alanylalanine, alanylglycine, and alanine have been determined in aqueous solution in 0.8 pH 5 at 25°C and 0.1 mol-dm^–3 (NaClO₄), using a combination of potentiometric and spectrophotometric techniques. The compositions of the formed complexes were determined and it was shown that dioxovanadium(V) forms two mononuclear 1:1 and 1:2 species with alanine of the type VO₂L and VO₂L₂^–, and two mononuclear 1:1 complexes with alanylpeptides of the type VO₂HL and VO₂L^–.