[SCAN] Developing stable copper(II) complexes for medical applications based on picolinic acid appended polyaza macrocycles

Scan Seminar

Title: Developing stable copper(II) complexes for medical applications based on picolinic acid appended polyaza macrocycles

Speaker: Luis Lima

From: Coordination and Supramolecular Chemistry Laboratory, ITQB

Abstract:

There is an increasing interest in the use of metallic radioisotopes in medicinal applications such as positron emission tomography (PET) and radioimmunotheraphy (RIT). Among the range of potentially useful metals, copper(II) has been receiving much interest due to the existence of several radioisotopes with different half-life times and emission properties as well as to the recent increase in the availability of most of these nuclides. Particularly interesting are copper-64 used for PET and copper-67 used for RIT.

One of the most effective classes of organic ligands for copper complexation is that of polyaza macrocycles. A common method to improve the complexation properties of such ligands is by appending suitable chemical functions on one or more of their macrocyclic amines. Additionally, picolinic acid is a well-known endogenous chelating agent that is able to bind strongly to many metal cations. As part of our current interest in the study of macrocyclic ligands for the stable complexation of metal cations for potential use in medicinal applications, we have recently been pursuing the development of polyaza macrocyclic ligands containing picolinic acid pendant arms for copper(II) complexation.

In this talk, three different approaches on copper(II) complexation with picolinic acid appended polyaza macrocycles will be presented, based on the different structures of the ligands. The properties of the developed copper(II) complexes will be discussed comparatively regarding their thermodynamic stability, their solid state and solution structures, as well as their inertness towards acid-assisted and reductive dissociation.