Structural hybridization of alepterolic acid with piperazine-benzamide motifs yields potent anticancer agents

Among the most pervasive malignancies affecting females worldwide, breast cancer is responsible for approximately 2.2 million new diagnoses and over 660,000 fatalities reported annually. Natural products represent an invaluable resource for the identification and development of potential innovative anti-cancer pharmaceuticals. In our present study, two series of derivatives were designed for synthesis by merging benzamide and piperazine with alepterolic acid. According to our observations, compounds 11s and 13r were cytotoxically more active against the MCF-7 cell line, showing IC₅₀ values of 4.93 ± 0.84 μM and 2.95 ± 0.52 μM, respectively. Further investigations revealed that under the treatment with 11s and 13r, morphology of MCF-7 cells was changed and their growth was inhibited both dose- and time-dependently. Additional Western blotting demonstrated a marked increase in the levels of cleaved caspases-3, -8, -9, cleaved poly (ADP ribose) polymerase (PARP) alongside Bax/Bcl-2 ratio in the 11s-treated MCF-7 cells. Similarly, treatment with 13r significantly upregulated the cellular cleaved caspases-3, -8, and PARP levels. Mechanistically, Western blotting revealed that 11s triggered both the intrinsic (via cleaved caspase-9/Bax upregulation) and extrinsic (via cleaved caspase-8 activation) apoptosis in MCF-7 cells, whereas 13r solely activated the extrinsic pathway. Conclusively, our findings demonstrated that the incorporation of benzamide and piperazine to alepterolic acid represents a promising approach for the discovery of new drug candidates.