Synthesis, spectral characterization of novel Pd(II), Pt(II) π-coordination compounds based on N-allylthioureas. Cytotoxic properties and DNA binding ability.

Four novel Pd2+ and Pt2+ mononuclear π-coordination compounds with general formula [M(HL)1,2Cl2], M=Pd2+, Pt2+ have been synthesized by reaction of [PdCl4]2-, [PtCl4]2- anions with N-allyl-4-morpholinethiocarboxamide (HL1) and N-Allyl-N'-tert-butylthiourea (HL2). All complexes have been characterized by single-crystal X-ray diffraction study and 1H, 13C NMR spectroscopy. Cytotoxic, cytostatic and proapoptotic activities of compounds have been determined in vitro on HeLa cell line and compared with cisplatin as etalon drug. All complex compounds possessed pronounced cytotoxic activity with IC50 indexes in range of 2·10-6-1.5·10-4М (IC50 of cisplatin is 5.7∙10-5М) and showed proapoptotic, cytostatic and antisyntetic influence higher or comparable with cisplatin. The comparative influence of cisplatin and synthesized metal complexes on pTZ19R* plasmid DNA was monitored by agarose gel electrophoresis. All compounds showed high affinity to DNA that correlates with observed cytostatic and proapoptotic levels. In general Pd(II) compounds showed higher activity than Pt(II) ones.