Selective Stabilization of Abasic Site-Containing DNA by Insertion of Sterically Demanding Biaryl Ligands

Biaryl derivatives that consist of one DNA‐intercalating unit and a sterically demanding component exhibit a specific behavior towards abasic site‐containing DNA (AP‐DNA) as determined by thermal DNA denaturation experiments, spectrometric titrations and CD spectroscopic analysis. Specifically, these ligands strongly stabilize AP‐DNA towards dissociation, whereas they do not or only marginally affect the melting temperature of regular duplex DNA. Perfect fit into imperfect DNA: Sterically congested biaryl derivatives are introduced as novel structural motifs for the design of ligands that bind to abasic site‐containing DNA (AP‐DNA). These ligands strongly stabilize AP‐DNA towards dissociation, whereas they do not, or only marginally, affect the melting temperature of regular duplex DNA (see scheme).