The Rapid Construction and Biological Evaluation of Densely Substituted Carbazoles Via I ₂ /H ₂ O‐Mediated Green Approach

We report a green and efficient iodine‐catalysed cascade reaction of indoles with α‐bromoacetophenones, enabling the rapid and highly regioselective construction of diverse carbazole scaffolds. Remarkably, this metal‐ and oxidant‐free protocol operates with only 5 mol% iodine in water, converting unprotected and protected indoles to carbazoles in excellent yields. A series of carbazole derivatives were synthesised under mild, operationally simple conditions, demonstrating broad functional group tolerance and excellent scalability to gram‐scale synthesis. The biological evaluation revealed that among the compounds tested, six compounds showed cell viability below 50% in A549 lung cancer cells and whereas nine compounds in SKOV3 ovarian cancer cells. Selectivity index calculations further indicated that one compound displayed moderate selectivity towards A549 cells, whereas five compounds showed preferential cytotoxicity against SKOV3 cells, highlighting the promising therapeutic potential of these scaffolds. Collectively, these findings underscore the medicinal relevance of the synthesised carbazole frameworks and the potential of this cost‐effective, chemo‐divergent and sustainable strategy for generating structurally complex, bioactive carbazole cores in anti‐cancer drug development.