The tridentate [HL, (4-[(2-(2-quinolinoimino)-3, 5-dibromobenzyl) amino] cyclohexanol)]Schiff base ligand was prepared from the condensation reaction of 2-quinoline carbaldehyde with the drug ambroxol. The prepared HL ligand was further used in the preparation of some new complexes via the reaction with La(III), Er(III) and Yb(III) metal ions. The geometry of the prepared complexes was proposed from elemental analysis, FT-IR, 1H NMR, thermal and magnetic susceptibility. 1H NMR showed that the three nitrogen atoms of the ligand were responsible for the complex formation. The thermal analysis technique provided a clear prospect about the decomposition steps of the Schiff base ligand and its complexes; as it also showed the number of water molecules present in the inner and outer coordination sphere of the prepared complexes. Upon these studies, an octahedral geometry for all of the complexes has been proposed. The Schiff base and its complexes have been screened for their antimicrobial activity. The biological activity results deduced that Er(III) complex possesses the highest activity.
Ahmed, Hoda; Mahmoud, Walaa H.; Al-Akraa, Islam M. Dr; and Mohamed, Gehad G., "Preparation, Characterization and Biological Activity of Novel Schiff Base Complexes based on La, Er and Yb Metal Ions" (2020). Chemical Engineering. 128.