New naphthalene-containing enamides: synthesis, structural insights and biological screening as potential anticancer...

Naphthalene and enamide derivatives are prevalent intracellular tubulin assembly inhibitors, and their optimization is critical for the creation of targeted anticancer agents. A number of new compounds containing naphthalen-1-yloxy and enamide functions connected through N'-acetoxyhydrazide linker were designed and synthesized and their biological activity were tested as possible anticancer agents. The cytotoxic activity of the constructed naphthalene-enamide analogs was studied on Huh-7 hepatocellular carcinoma cell line. The analogs 5f and 5g with 4-methylbenzene and 4-methoxybenzene in the 3,4,5-trimethoxyenamide moiety were proved to have outstanding cytotoxic activity with superior cytotoxic action (IC₅₀ = 2.62 and 3.37 µM, respectively) toward the growth of Huh-7 cells compared to conventional anticancer agent Dox (IC₅₀ = 7.20 µM). In addition, the most efficient members had strong inhibitory efficacy against tubulin beta polymerization. Additionally, the most potent analog had cellular cycle arrest at G2/M phase while lowering the cellular population at G1 and S phases relative to controls. Fluorochrome Annexin-V and PI FACS staining assessment disclosed that Huh-7 hatched with compound 5f elevated the percentage of total apoptosis compared to untreated controls. Furthermore, compound 5f had a strong pro-apoptotic impact through triggering the intrinsic mechanism of apoptosis. This mechanistic route was verified via FACS experiment that indicated a remarkable drop in the extent of MMP compared with the controls.