Iron(II) and Copper(II) Ions Modulating Binding Interaction of Sugar-Based Silatrane With DNA: Analytical and Theoretical Validation.

Research on molecular systems capable of interacting with DNA through binding, modification, or cleavage remains important in medicinal chemistry. In this study, we report the design and synthesis of a new D-glucamine-based Schiff base containing a triazolyl silatrane probe (6) and its Fe(II) and Cu(II) complexes, followed by investigation of their interactions with calf thymus DNA (CT-DNA). The synthesized ligand and its metal complexes were characterized by elemental analysis, FT-IR, UV-vis spectroscopy, ESI-MS, and NMR spectroscopy (1H and 13C for the free ligand). DNA-binding properties were evaluated by UV-vis absorption spectroscopy, ethidium bromide (EtBr) displacement fluorescence assays, and molecular docking studies. The combined experimental and computational results indicate that ligand 6 interacts predominantly with CT-DNA through groove binding, whereas complexation with Fe(II) or Cu(II) enhances DNA-binding affinity and modulates the interaction toward a mixed groove-binding/intercalative mode. The higher binding constants, enhanced fluorescence quenching, and favorable docking interactions observed for the metal complexes support this metal-induced modulation of DNA-binding behavior. Overall, the findings demonstrate that metal complexation can tune both the strength and mode of DNA binding, highlighting a potential strategy for designing silatrane-based metal complexes with DNA-targeting applications.