Synthesis, characterization, electrochemistry and in vitro cytotoxicity of a new “Triazole-Maltol” ligand and its platinum(II) complex

The 3-methoxy-2-methyl-4H-pyran-4-one (MeO-Malt) was incorporated into the structure of 1H-1,2,3-triazole-4-carboxylate via click chemistry. The new ligand methyl-1-((3-methoxy-4-oxo-4H-pyran-2-yl)methyl)-1H-1,2,3-triazole-4-carboxylate (3) was reacted with platinum to give mononuclear complex 4. Investigation of the crystal structure of the free ligand 3 highlighted a chain structure established by hydrogen bonding between triazole units and carboxylic groups. The platinum complex was characterized by ATR-IR, NMR and UV–vis spectroscopies. Cyclic voltammograms of 3 and 4 were also discussed. Furthermore, they were tested for cytotoxic activity against squamous cell carcinoma (A431), lung cancer (A549), human melanoma (A375 and HT144) and human colorectal cancer (HT29 and HCT116) cells.