Solvent dependent selective alkylation of a bis(sulfonamide) for the synthesis of a DNA-binding chiral polyamine

A new optically active linear polyamine has been efficiently prepared and its DNA binding abilities studied by UV melting experiments. The key step for this synthesis was the selective monoalkylation of the corresponding bis(sulfonamide). Thus, it is possible to obtain mono or dialkylated compounds by simply changing the reaction conditions. These results are explained in terms of conformational preferences and solvophobic effects.