A Comprehensive Review on Fused Heterocyclic as DNA Intercalators: Promising Anticancer Agents

Since the discovery of DNA intercalating agents (by Lerman, 1961), a growing number of organic, inorganic, and metallic compounds have been developed to treat life-threatening microbial infections and cancers. Fused-heterocycles are amongst the most important group of compounds that have the ability to interact with DNA. DNA intercalators possess a planar aromatic ring structure that inserts itself between the base pairs of nucleic acids. Once inserted, the aromatic structure makes van der Waals interactions and hydrogen-bonding interactions with the base pairs. The DNA intercalator may also contain an ionizable group that can form ionic interactions with the negatively charged phosphate backbone. After the intercalation, other cellular processes could take place, leading ultimately to cell death. The heterocyclic nucleus present in the DNA intercalators can be considered as a pharmacophore that plays an instrumental role in dictating the affinity and selectivity exhibited by these compounds. In this work, we have carried out a revision of small organic molecules that bind to the DNA molecule via intercalation and cleaving and exert their antitumor activity. A general overview of the most recent results in this area, paying particular attention to compounds that are currently under clinical trials, is provided. Advancement in spectroscopic techniques studying DNA interaction can be examined in-depth, yielding important information on structure-activity relationships. In this comprehensive review, we have focused on the introduction to fused heterocyclic agents with DNA interacting features, from medicinal point of view. The structure-activity relationships points, cytotoxicity data, and binding data and future perspectives of medicinal compounds have been discussed in detail.