A novel Pt2+ complex containing 1,4-benzodioxan-6-amine: Stability, DNA binding, and antitumor effects against human breast cancer cells

In this work, a new platinum(II) complex was prepared by the reaction of K₂PtCl₄ with 1,4-benzodioxan-6-amine (bda) at room temperature in the molar ratio 2:1 (L:M). The complex was characterized by physicochemical (elemental analysis, TGA/DTA, and conductivity measurements) and spectroscopic methods (UV–Vis, FTIR, ¹H, ¹³C and ¹⁹⁵Pt NMR). According to the spectroscopic data, two bda ligands coordinate to the platinum ion in a monodentate manner through the nitrogen atom to give the complex cis-[PtCl₂(bda)₂]. Stability studies were carried out under different conditions and showed that the complex is stable in pure DMF, although it undergoes slow solvolysis in DMSO. The interaction of this complex with calf thymus DNA (CT-DNA) was studied using circular dichroism (CD), electronic absorption and fluorescence spectroscopy. The complex binds to CT-DNA with a K_b value of 1.06 ​× ​10³ ​M⁻¹ and according to data from CD and fluorescence spectroscopy, appears to interact with DNA by electrostatic forces and or other no intercalative binding mode. Compared to cisplatin, the complex exhibited good cytotoxic activity and selectivity against the MCF-7 tumor cell line, displaying an IC₅₀ value of 17.33 ​± ​1.1 ​μM, as well as inhibited MCF-7 ​cells migration.