A novel strategy for site-directed chemical reactions in single stranded DNA--absorption and NMR spectroscopic studies of model compounds.

A new and simple model enabling a chemical species to be brought to a preselected site in single strand DNA is reported. Two oligonucleotides containing a propanediol linkage were hybridized to their complementary sequences with an extra-base opposite the propanediol derivative. Absorption studies results shown that the addition of a bisacridine derivative strongly increased the stabilities of both duplexes when added in a 1:1 ratio. NMR studies on one of these duplexes brought evidence of the intercalation of the bisacridine at the position involving the propanediol linkage. These results suggest that this system could be used to target a specific reaction at a preselected position using the bisacridine derivative as carrier for the reactive species.