The synthesis and condensation of o-vanillin with 2-amino-3-methyl pyridine in a 1:1 ratio resulted in the formation of a Schiff base 3-methoxy-2-((3-methyl pyridine-2-ylimino) methyl) phenol. Six lanthanum complexes (LaL, CeL, PrL, NdL, SmL and GdL) were prepared using the Schiff base ligand. The antimicrobial evaluation resulted in a specific microorganism against which the compound was tested. All compounds showed significant anticancer activity against human breast cancer cell lines (MCF 7) in various concentration ranges (6.25, 12.5, 25, 50 and 100 µg ml–1), as determined by the MTT assay. Herein, we explain the synthetic methods of various La(III) complexes with their characterization and application of antimicrobial and cytotoxic activity against cancer cell lines, as well as the potential of heterocyclic compounds containing nitrogen, oxygen, and sulphur with enhanced activity against cancer and microbial infections. The organic bulkier ligands with Lanthanum (III) metal ions are used as a drug transport vehicle towards the biological systems. The synthesis of lanthanum complexes with the Schiff base ligand derived from o-vanillin and 2-amino-3-methyl pyridine provides a probability for the development of new therapeutic agents.
