A β-D-Allopyranoside-Grafted Ru(II) Complex: Synthesis and Acid-Base and DNA-Binding Properties

A new ruthenium(II) complex grafted with beta-D-allopyranoside, Ru(bpy)(2)(Happip)(ClO4)(2) (where bpy = 2,2'-bipyridine; Happip = 2-(4-(beta-D-allopyranoside)phenyl)imidazo[4,5-f][1,10]phenanthroline), has been synthesized and characterized by elemental analysis, H-1 NMR spectroscopy, and mass spectrometry. The acid-base properties of the complex have been studied by UV-visible and luminescence spectrophotometric pH titrations, and ground- and excited-state ionization constants have been derived. The Ru(II) complex functions as a DNA intercalator as revealed by UV-visible and emission titrations, salt effects, steady-state emission quenching by [Fe(CN)(6)](4-), DNA competitive binding with ethidium bromide, DNA melting experiment, and viscosity measurements.