Design, synthesis and bioactivity evaluation of phosphinanes as potential anticancer agents

The development of novel anticancer agents is crucial to the ongoing effort to combat cancer. In this study, six-membered phosphorus heterocycles (phosphinanes) were designed, synthesized, and evaluated as potential antiproliferative agents. A series of novel phosphinane derivatives was obtained through structural modifications of 1-phenylphosphinane 1-oxide and 1-phenylphosphinan-4-one 1-oxide, achieving high overall yields. The dearomatization of the phenyl group attached to the phosphorus atom is a pivotal step in the P-substituent modification. The synthesized compounds, differing in steric and electronic properties, were assessed for in vitro cytotoxicity against colon (SW480, SW620, HCT116) and prostate (PC3) cancer cell lines. Among them, three compounds (2, 8, and 11) exhibited activity at ≤ 10 µM, with compound 11 outperforming cisplatin in all assays. This compound was the most potent activator of late apoptosis in PC3, SW480, and HCT116 cells (by 87.5-95.5%) and inhibited IL-6 secretion from all studied tumor cells by 71.8-96.8%. These results position phosphinanes as a tractable scaffold for further development in anticancer drug discovery.