Drug-induced stabilisation of a mismatched C-T base pair in a DNA hairpinElectronic supplementary information (ESI) available: 1H NMR spectra of the hairpin sequence. See http://www.rsc.org/suppdata/cc/b3/b305337g/

We have shown that a key feature of drug binding, namely specific G-C base pair recognition at a 5'-TG step, can induce a number of novel structural features when an extrahelical base is inserted in close proximity to the drug binding site; we have clearly demonstrated the formation of a stabilised C-T mismatched base pair at a non-terminal site.