Synthesis of Pt(II) complexes of the type [Pt(1,10-phenanthroline)(SArFn)2] (SArFn = SC6H3-3,4-F2; SC6F4-4-H; SC6F5). Preliminary evaluation of their in vitro anticancer activity

A series of Pt(II) complexes of the type [Pt(1,10-phenanthroline)(SArFn)2] (SArFn = SC6H3-3,4-F2(1); SC6F4-4-H (2); SC6F5(3)) were synthesized from [Pt(1,10-phenanthroline)(Cl)2] and [Pb(SArFn)2] via metathesis reactions. The complexes were fully characterized including the unambiguous determination of their molecular structures by single-crystal X-ray diffraction techniques, showing the metal centers to be into a slightly distorted square-planar environments. The in vitro cytotoxic activity of the complexes was evaluated on six cancerous cell lines, i.e: glial cells of nervous central system (U-251), prostate (PC-3), leukemia (K-562), colon (HCT-15), breast (MCF-7) and lung (SKLU-1); we also included a healthy cell line of COS-7 (African green monkey kidney) for comparative purposes. We found that complex 2 was selective for PC-3. In addition, the IC50 values for the series of complexes were determined using the U-251, HCT-15 and SKLU-1 cancerous cell lines, as well as in the healthy cell line (COS-7), where complex 1 exhibited the best activity, with IC50 values going from 4.56 to 4.78 μM. These studies where further complemented with DNA docking theoretical calculations and DNA affinity experiments. [Pt(1,10-phenantroline)(SArFn)2] (SArFn = SC6H3–3,4-F2(1); SC6F4–4-H (2); SC6F5(3)) complexes were synthesized and characterized and their in-vitro cytotoxic activity evaluated on six cancerous cell lines and a healthy cell line. Complex 1 was the best with IC50 values better than cisplatin. DNA docking and DNA affinity experiments support these conclusions. [Display omitted] •Three complexes [Pt(1,10-phenanthroline)(SArFn)2] were synthesized and characterized.•The complexes showed high activity against different cancer cell lines.•The number and position of “F” in the thiolates affects the activity of the complexes.•Theoretical docking calculations support the relevance of the fluorinated ligands.•DNA affinity experiments indicate that intercalation of the complexes on the DNA occurs.