A Garratt-Braverman cyclization route towards the synthesis of phenanthridine derivatives and their DNA-binding studies

Abstract

Garratt-Braverman cyclization has been employed to synthesize a series of dihydroisofuran fused phenanthridine derivatives. The established protocol proposes a simpler synthetic alternative to have access to these therapeutically relevant cytotoxic scaffolds. Single crystal X-ray data unambiguously confirmed the structures of the synthesized phenanthridine derivatives. UV–Vis absorption titration with calf-thymus DNA followed by fluorescence-based competitive ethidium bromide displacement assay established the synthesized target compounds as potent DNA-intercalating agents with intrinsic binding constant of the range 103-105. Results obtained from the molecular docking further justified the spectroscopically obtained results.