Abstract: The present invention provides a series of novel bifunctional molecules based on viologen linked acridine, bisacridine and bisacridinium salts of the general formula 1 (1a, 1b, 1c and 1d) and or pharmaceutically acceptable derivatives thereof, which can be used as phototherapeutic and catalytic photoactivated DNA cleaving agents. These molecules are very stable and exhibit high solubility in buffer at physiological conditions. They undergo strong binding with DNA through intercalation and groove binding interactions and show remarkably high affinity for poly(dA).poly(dT) sequences. Upon photoactivation, they cleave DNA catalytically and selectively at guanine (G) sites in duplex DNA exclusively through cosensitization mechanism with a preference for 5′-G over 3′-G. They induce unusally high specificity of cleavage at G site of the AG two base bulge sequences.

Abstract: The present invention provides a series of novel bifunctional molecules based on viologen linked acridine, bisacridine and bisacridinium salts of the general formula 1 (1a, 1b, 1c and 1d) and or pharmaceutically acceptable derivatives thereof, which can be used as phototherapeutic and catalytic photoactivated DNA cleaving agents. These molecules are very stable and exhibit high solubility in buffer at physiological conditions. They undergo strong binding with DNA through intercalation and groove binding interactions and show remarkably high affinity for poly(dA).poly(dT) sequences. Upon photoactivation, they cleave DNA catalytically and selectively at guanine (G) sites in duplex DNA exclusively through cosensitization mechanism with a preference for 5′-G over 3′-G. They induce unusally high specificity of cleavage at G site of the AG two base bulge sequences.