Synthesis, characterization of ruthenium(II) complex of 1,3,8-trihydroxy-6-methyl-anthraquinone (emodin) and its binding behavior with c-myc G-quadruplex

In this paper, a novel ruthenium(II) complex of emodin, Ru(bpy)2Emodin(RBL17, bpy = 2,2ʹ-bipyridine; Eomdin = 1,3,8-trihydroxy-6-methyl-anthraquinone), has been synthesized and characterized by ESI-MS, 1H NMR, 1H–1H COSY and electronic spectra. The binding behavior of RBL17 with c-myc G4 DNA has been further investigated by ITC (isothermal titration calorimetry), FRET (fluorescence resonance energy transfer) and 1H NMR spectra, as well as spectroscopic methods. Those results showed that this complex has the ability to bind and stabilize the conformation of c-myc G-quadruplex via groove binding mode. Taken together, ruthenium(II) complex of emodin can act as a potential inhibitor in chemotherapy by targeting to c-myc G4 DNA.