Cancer is one of the most prevailing disease conditions, which occurs due to uncontrolled cell division either due to natural mutation to the genes or due to changes induced by physical, chemical, or biological carcinogens. According to WHO, it is the second leading cause of death worldwide and has reported 10 million deaths in 2020. Hence, there arises the need for better chemotherapies and DNA intercalators are one such emerging therapy for cancer. DNA intercalating agents reversibly intercalate with the double‐helical structure of DNA by interacting with adjacent base pairs and disrupting the structure of DNA and thereby causing cell death. Here, we discuss the different classes of organo‐intercalators used in cancer therapy describing their anticancer and intercalation ability by different methods along with their structure–activity relationship and mechanism of action.

Indole moiety is a magnificent nucleus in the development of anticancer drugs. The pharmacological profile of indole is excellent in targeting a wide range of proteins, enzymes. An indole has a nitrogen atom that is capable of forming hydrogen bonds with the targets emphasizing its potential. Many studies have demonstrated the effectiveness of indole in the treatment of cancer by working through various pathways. Indole-based drugs got market approval to be used as chemotherapeutics, such as vincristine and vinblastine which encourage researchers to work on indole derivatives for cancer treatment with a better pharmacokinetic profile. This prompted us to review on indole derivatives as anticancer agents to bring out their potential derivatives under study. This study encompasses literature published between 2014 and 2021 on indole scaffold that exhibits in vitro and in vivo potential against cancer by searching PubMed, Google Scholar, and Science Direct databases. The search terms were "anticancer", "indole", "cell lines", "structure-activity relationship" and "cytotoxic activity."[a] A.

Carcinoma, characterized by abnormal growth of cells and tissue, is a ubiquitously leading cause of mortality across the globe due to some carcinogenic factors. Currently, several anticancer agents are commercially available in the global market. However, due to their resistance and cost, researchers are gaining more interest in developing newer novel potential anticancer agents. In the search for new drugs for clinical use, the tetrazole ring system has emerged as an exciting prospect in the optimization studies of promising lead molecules. Among the various heterocyclic agents, tetrazole-containing compounds have shown significant promise in the treatment of a wide range of diseases, particularly cancer. Here, in this review, we focused on several synthetic approaches for the synthesis of tetrazole analogs, their targets for treating cancer along with the biological activity of some of the recently reported tetrazole-containing anticancer agents.

Cancer is the second leading cause of death globally, with 9.6 million deaths yearly. As a life-threatening disease, it necessitates the emergence of new therapies. Resistance to current chemotherapies drives scientists to develop new medications that will eventually be accessible. Because heterocycles are so common in biological substances, compounds play a big part in the variety of medications that have been developed. The "Master Key" is the benzimidazole nucleus, which consists of a six-membered benzene ring fused with a five-membered imidazole/ imidazoline ring, which is an azapyrrole. One of the five-membered aromatic nitrogen heterocycles identified in American therapies that have been approved by the Food and Drug Administration (FDA). Our results show that benzimidazole's broad therapeutic spectrum is due to its structural isosteres with purine, which improves hydrogen bonding, electrostatic interactions with topoisomerase complexes, intercalation with DNA, and other functions. It also enhances protein and nucleic acid inhibition, tubulin microtubule degeneration, apoptosis, DNA fragmentation, and other functions. Additionally, readers for designing the more recent benzimidazole analogues as prospective cancer treatments.

Heterocyclic compounds are a class of compounds that is deeply intertwined with biological processes and are found in about 90% of commercially available medicines. They serve a critical function in medicinal chemistry and focused in the field of medication development for its intensive research due to their broad variety of biological effects because of their intriguing molecular architecture, indoles are good candidates for drug development. It is a bicyclic structure consisting of a six-membered benzene ring fused to a five-membered pyrrole ring with several pharmacophores that yield a library of different lead compounds. Human cancer cells have been demonstrated to be inhibited by indoles in the development of new anticancer medicines. This is the first comprehensive review to focus on current methodologies for incorporating indole moiety, with their mechanistic targets as anticancer drug, in order to shed light on the logical development of indole based anticancer treatment options with high efficacy. This compiled data may serve as a benchmark for modifying existing ligands in order to design novel potent molecules through excellent yield synthesis techniques.