Modulating water-exchange rates of lanthanide(III)-containing polyaminopolycarboxylate-type complexes using polyethylene glycol

Abstract

We have synthesized a series of Ln(III)-containing polyethylene glycol conjugates and studied the structural and electronic properties of these complexes. These studies demonstrate that polyethylene glycol can be used to fine-tune water-exchange rates of Ln(III)-containing polyaminopolycarboxylate-type complexes; this control is desirable in developing Ln(III)-containing contrast agents for magnetic resonance imaging.

Fig. 1

Structures of Ln^III-containing PEG conjugates 1a–d and 2a–d and Y^III-containing conjugates 3a–d.

Scheme 1

Synthetic route to Ln^III-containing PEG conjugates 1a–d and 2a–d and Y^III-containing conjugates 3a–d.