Chelating power of LR-74, a new AGE-inhibitor

Theoretical calculations based on pseudo-potentials were used to determine the structures of the complexes formed between Cu2+ ion and 2-(8-quinolinoxy)propionic acid (LR-74), which is a potent inhibitor of non-enzymatic glycation reactions. The most stable among such complexes consist of one atom of copper and two molecules of inhibitor, [Cu(LR-74)2], and possess a distorted octahedral geometry. In the complex containing a single molecule of inhibitor, the square planar form, [Cu(LR-74)(H2O)]+, is slightly more stable than the octahedral form, [Cu(LR-74)(H2O)3]+, in solution. All octahedral complexes exhibit strong Jahn–Teller distortion that results in substantially increased axial distances.