We report herein the implementation of coordination complexes containing two types of cationic moieties, i.e. pyridinium and ammonium quaternary salt, as potential inhibitors of human cholinesterase enzymes. Utilization of ligands containing NNO-coordination site and binding zinc metal ion allowed obtaining mono- and tetra-nuclear complexes with corner and grid structural type respectively, thus affecting the overall charge of the compounds (from +1 to +8). It enabled for the first time to examine the multivalency effect of metallosupramolecular species on their inhibitory abilities towards acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Importantly, resolution of the crystal structures of the obtained enzyme-substrate complexes provided a better understanding of the inhibition process at the molecular level.
