TDMQ chelators have been designed as drug-candidates for the regulation of copper homeostasis and for the reduction of the oxidative stress in the brain of Alzheimer's patients. To achieve suitable biological properties and high Cu(II) selectivity in a zinc-rich medium, TDMQ ligands must meet critical coordination chemistry requirements related to the structures of the CuII-TDMQ complexes. The correlation between X-ray diffraction structures of Cu- and Zn-TDMQ complexes and their physicochemical properties should therefore help to draw pertinent correlations between structure and properties of the drug-candidates, and to select the most promising ones for biological studies. Here we report the X-ray structures of single crystals of Cu-TDMQ36, and of the zinc complexes of TDMQ35, TDMQ36 and TDMQ22. Comparison with the already reported structures of other copper and zinc complexes of TDMQ then allows to specify the structure requirement for potentially more efficient drugs.