Synthesis and DNA Binding Properties of Bis-9-acridinyl Derivatives Containing Mono-, Di-, and Tetra-Viologen Units as a Connector of Bis- Intercalators.

Bis-9-acridinyl derivatives 1–3 containing mono-, di-and tetra-viologen units as a rigid connector were synthesized. The binding studies of these intercalators for natural and synthetic DNAs showed that these compounds act as bis-intercalators where viologen moieties lie in the minor groove of the DNA duplex. The DNA binding affinity of the intercalators was enhanced with an increase in the number of the viologen unit.