This week’s molecule comes from research at the University of Calabria, Italy about Pt(II) and Pd(II) complexes which may be active as anticancer agents (Pucci, D.; Bellusci, A.; Bernardini, S.; Bloise, R.; Crispini, A.; Federici, G.; Liguori, P.; Lucas, M.F.; Russo, N.; Valentini, A., Dalton Transactions, 2008, 5897-5904). The research focused on the synthesis of metal-complexes with two chelating ligands, 2-hydrocyclohepta-2,4,6-trienone (tropolone) and dihexadecyl-2,2′-bipyridine-4,4′-dicarboxylate (bipy), around either Pt(II) or Pd(II) metal centers. Pt is often used as a metal center in anti-cancer drugs, and Pd was introduced with the hope of reducing the toxicity of previous Pt drugs. Both compounds were successfully synthesized and analyzed by X-ray diffraction.
The geometry about the Pt(II) metal is distorted square planar and the molecule is essentially planar. The metal complexes were tested in vitro against the human prostate DU145 and hormone-sensitive LNCaPcell lines. The two chelating ligand system was more active at cell growth inhibition than other studied complexes. The complexes are known to inhibit tumor growth by binding to a cell’s DNA and inducing cell apoptosis or necrosis. These metal-based anticancer drugs are important because they seem to be more effective in lower doses, which would decrease toxicity. Also the specific bipy ligand which allows strong pi-pi bonds may cause further conformational changes in a cell’s DNA which might increase efficiency. The Calabria researchers plan to investigate the mechanisms of these inhibitory complexes in future work.
This molecule interested me because of its long, linear chains and near planar shape. It’s cool to take a look at the potential drugs of tomorrow.