Novel bis-phenanthridine derivatives with easily tunable linkers, study of their interactions with DNA and screening of antiproliferative activity.

Series of novel peptide-bridged bis-phenanthridine derivatives as well as corresponding monomers were prepared by solid phase peptide synthesis, which allowed easy and fast tuning of compound properties. Interactions of new derivatives with double stranded DNA were strongly structure-dependent, among which the most interesting is bis-phenanthridine derivative forming intramolecular excimer, with specific fluorescence band sensitive to the pH as well as on the interactions with ds-DNA. Moreover, at variance to commonly high cytotoxic effects of phenanthridine derivatives, here studied monomeric as well as bis-phenanthridine derivatives exhibited negligible antiproliferative activity on a panel of human cell lines, which makes them promising lead compounds for development of new spectrophotometric markers.