• Alain Zahn
  • Christian J. Leumann



Biphenyl-dna, Dna, Hydrophobic base-pairs, Hydrophobic interactions, Stacking interactions, Suzuki coupling


We report on the pairing properties of oligodeoxynucleotides containing chemically functionalized biphenyl residues instead of natural nucleobases. The synthesis of the corresponding C-nucleosides with one or two nitro- or methoxy groups, resp. in the distal phenyl ring was accomplished via Suzuki coupling of a protected 4-bromophenyl-C-nucleoside with the correspondingly substituted phenylboronic acids or esters. The interstrand hydrophobic and/or stacking recognition properties of the aromatic units were probed by Tm-measurements on duplexes containing single or triple incorporations. We found a strong dependence of duplex stability from the nature of the substituents (donor vs. acceptor). The stability of duplexes with one biphenyl-pair increases in the order of donor–donor < acceptor–donor < acceptor–acceptor pairs. On the other hand in the triply modified duplexes stability increases in the order acceptor–acceptor < donor–acceptor < donor–donor pairs. It thus appears that interactions to the nearest neighbor natural base-pairs are preferred by acceptor modified biphenyls while the interactions between biphenyls are most stable with opposing donor modified biphenyls.




How to Cite

A. Zahn, C. J. Leumann, Chimia 2007, 61, 159, DOI: 10.2533/chimia.2007.159.