New Peptidyl-Anthraquinones: Synthesis and DNA Binding

Abstract

Aminoacyl-hydroxy-anthraquinones bearing glicyl, varyl, lysyl and tryptophanyl residues in the side-chain were synthesized as new potential DNA-directed drugs. These compounds bind very tightly to double-stranded DNA by intercalating their planar portion into the nucleic acid and further stabilizing the complex through electrostatic contacts with the backbone phosphates. All protonated groups in the side-chains participate in the latter process. The free energy of DNA-binding corrected for the electrostatic contribution is similar for the lysyl and glicyl derivatives, which points to a common geometry of intercalation.