Synthesis and iron coordination properties of schizokinen and its imide derivative

Abstract

The iron(III) affinity constants for schizokinen and its imide derivative are reported for the first time. Surprisingly, schizokinen possesses a higher affinity for iron(III) than desferrioxamine B; log K_Fe^III (FeL), 36.2 and 30.6, respectively. This increase in value is associated with the substitution of one hydroxamate function by an α-hydroxycarboxylate grouping. By virtue of the similarity of siderophore–iron(III) complexes and siderophore–gallium(III) complexes, schizokinen (which is a Gram positive siderophore) has potential for ⁶⁸Ga PET-based imaging.