A Schiff Base Macrocycle Ligand and Its Mg(II) and Cd(II) Complexes: Spectral Properties with Theoretical Understanding and Biological Activity

Abstract

Abstract Simple Schiff base condensation is employed to prepare a macrocyclic ligand (L1H 4 ) with a support of intramolecular hydrogen templating effect. Reaction with Mg(II) and Cd(II) a total number of three complexes namely, [L1 4– (Mg 2+ ) 2 ] ( 1 ), [L1 4– (Cd 2+ ) 2 (H 2 O) 2 ] ( 2 ) and [H 2 L1 2– Cd 2+ ] ( 3 ) is obtained under same reaction condition and same solvent. Ligand and the complexes are identified and characterized by different spectroscopic techniques. Further the structural geometry and absorption spectra were analyzed by DFT (for ligand)/ semi‐empherical method (for complexes). Considering the involvement of metal ions in the regulation of cell proliferation we further explored the effect of these macrocycle confined metal complexes on human skin fibroblast cell line (GM00637) with or without the presence of fibroblasts stimulant (extracts from Calendula officinalis and Morinda citrifolia ). Also, same study has been performed with ligand and metal ion without mixing them. Among these Cd(II) complexes are found most promising. Luminescent property for the ligand and all the complexes are also examined and analyzed theoretically.