Tin(II) and Tin(IV) Complexes Incorporating the Oxygen Tripodal Ligands [(-CR)Co{P(OEt)O}], (R = H, Me; Et = -CH) as Potent Inflammatory Mediator Inhibitors: Cytotoxic Properties and Biological Activities against the Platelet-Activating Factor (PAF) and Thrombin.

Metal complexes displaying antiplatelet properties is a promising research area. In our methodology, Platelet-Activating Factor (PAF), the most potent lipid pro-inflammatory mediator, serves as a biological probe. The antiplatelet activity is exerted by the inhibition of the PAF-induced aggregation in washed rabbit platelets (WRPs) and in rabbit plasma rich in platelets (rPRPs). Herein, the synthesis and biological investigation of a series of organometallic tin(II) and tin(IV) complexes, featuring the oxygen tripodal Kläui ligands [(-CR)Co{P(OEt)O}], {R = H, (L); Me (L*)}, are reported. Reaction of NaL () and NaL* () with SnCl, yielded the rare four-coordinate LSnCl () and L*SnCl () complexes. Accordingly, LSnPh () and L*SnPh () were prepared, starting from PhSnCl. Characterization includes spectroscopy and X-ray diffraction studies for , and . The antiplatelet activity of the lead complexes and (IC = 0.5 μΜ) is superior compared to that of and , while both complexes display a pronounced inhibitory activity against thrombin (IC = 1.8 μM and 0.6 μM). The in vitro cytotoxic activities of and on human Jurkat T lymphoblastic tumor cell line is higher than that of cisplatin.