Exploring the Antitumor Potential of New Indazole-indolizines Designed by Molecular Hybridization

Background: Cancer represents the major health problem faced by the population of the world, remaining one of the main causes of death. Hence, the development of new targeted antitumor drugs with high efficacy and lower toxicity is still needed. Objective: As a continuation of our work to discover new molecules with cytotoxic properties, two heterocyclic scaffolds, namely indolizine, and indazole, were combined in the same molecule, aiming to improve the bioactivity. This article focused on the synthesis, characterization, and biological evaluation of a series of new indazole-indolizine hybrid compounds. Methods: The biological potential of the synthesized compound was investigated in vitro against the human farnesyltransferase enzyme and NCI 60 tumor cell lines panel. While the farnesyltransferase inhibitory activity was modest, a very good antiproliferative action was observed for compound 4a, which, at a concentration of 10 μM, inhibited the growth of 20 types of cancer cells by more than 50% and showed cytotoxic action against the ovarian cancer cell line OVCAR-4. Results: A series of novel indazole-indolizine hybrids were synthesized via a [3+2] cycloaddition reaction, fully characterized and biologically evaluated for antitumor potential. Conclusion: Compound 4a could be a promising starting point in the development of new antitumoral agents. Further biological investigations will be performed to identify the biological target of the compounds. Moreover, different synthetic strategies to introduce new substituents on the indolizine core will be addressed.