Abstract A series of three platinum (II) phenanthroimidazoles each containing a protonable side-chain appended from the phenyl moiety through copper (I)-catalyzed azide–alkyne cycloaddition (CuAAC) were evaluated for their capacities to bind to human telomere, c-Myc, and c-Kit derived G-quadruplexes. The side-chain has been optimized to enable a multivalent binding mode to G-quadruplex motifs, which would potentially result in ...