New Pathways to Cancer‑Killing Molecules

A team of chemists created a set of special phosphorus‑containing compounds by first expanding a small ring and then adding chlorine atoms in two steps. They focused on molecules that carry a hydroxyl group inside a six‑membered ring, turning them into “tetrahydrophosphinine oxides. ” The researchers were able to distinguish two mirror‑image versions of one key compound using crystal X‑ray data. Once they knew the exact shapes, they used nuclear magnetic resonance to confirm the details of each isomer. Analysis of the crystal structures revealed that subtle hydrogen‑chlorine and oxygen‑hydrogen contacts differ between the two forms, which explains why they pack differently in a solid block.

The less crowded isomers were then chemically modified by attaching phosphorus or sulfur groups, a process called phosphinoylation and thiophosphinoylation. These new derivatives keep the core ring but add extra functional groups that can interact with biological targets. When tested against two human cancer cell lines—U266 myeloma and A2058 melanoma—the modified molecules showed strong activity. At a concentration of 100 µM, cell survival dropped sharply for one original compound and its two modified versions, regardless of the side chain attached. This suggests that these phosphorus‑based structures could be promising leads for future anticancer drugs.

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