The interaction of salicylaldehydebenzoylhydrazone with Ca

This article reports a spectrophotometrical study of complex formation between Mg2+, Ca2+ and Salicylaldehydebenzoylhydrazone (SBH) with Mg2+ and Ca2+. At pH > 9.11, the unprotonated species of SBH, L forms a monocomplex with Mg2+ (affinity constant : 4.80 × 103 M-1) and with Ca2+ (affinity constant : 750 M-1). In neutral media, where the SBH ligand is present under the monoprotonated LH species, SBH does not possess any measurable affinity for Mg2+ or Ca2+ with for both metals a pM value of 5.0 for [Μ] = 1 × 10-5 M, [SBH] = 1 × 10-4 M and pH 7.4. These results are of interest for the iron-overload chelating therapy in which the chelating drug should be able to only form stable complexes with iron but not with the other metallic cations essential for the metabolism