Polycations. 6. polycationic heterocyclic salts: Their synthesis and effect on double-stranded DNA

A new series of compounds, intermediate-sized ring systems in which cationic sites have been incorporated into the primary ring system at heteroatoms, were synthesized by the reaction of α,ω-dihalides with either α,ω-ditertiary amines or an α,ω-ditertiary phosphine. Judicious choice of the reaction conditions allowed these polycationic heterocycles to be generated in excellent yields, whereas prior reported efforts with similar reagents under other reaction conditions have led to only polymeric materials. These heterocyclic polycations exhibit an interaction with double-stranded DNA resulting in a change in the conformation of the DNA as evidenced through the circular dichroism (CD) spectrum.