Mn2+ Complexes with Pyridine-Containing 15-Membered Macrocycles: Thermodynamic, Kinetic, Crystallographic, and 1H/17O Relaxation Studies

Abstract

Complexes of divalent manganese with 15-membered macrocycles having pyridine and 2O/2N or 4N donor atoms inside the cycle were investigated. Protonation constants of the ligands and stability constants of the complexes with Mn(2+) and biologically important metal ions were determined.

Kinetic inertness of the Mn(2+) complexes was investigated at different pH and Zn(2+) concentrations. Relaxometric studies of the Mn(2+) complexes were carried out.

Keywords

• nuclear magnetic resonance
• relaxometric studies
• crystal structures
• decomplexation kinetics
• MRI contrast agents
• water exchange rate
• manganese(II) complexes
• imaging MEMRI
• stability constants