Platinum dibromide complexes with 10-(aryl)phenoxarsines: synthesis, structure, luminescent and biological properties

The reactions of 10-(aryl)phenoxarsines (L1 = 10-(4-tolyl)phenoxarsine, L2 is 10-(4-fluorophenyl) phenoxarsine, L3 is 10-(3-fluorophenyl)phenoxarsine, and L4 is 10-(2-methoxyphenyl)phenoxarsine) with Pt(COD)Br2 afford platinum(II) complexes [Pt(L1–4)2Br2] (I–IV). The complexes are characterized by elemental analysis, IR spectroscopy, mass spectrometry, and NMR (1Н, 13С, 195Pt) spectroscopy. The Pt(II) complexes in solutions exist as two isomers mutually exchanging at a rate intermediate in the NMR time scale. The molecular structures of complexes cis-II · chloroform, trans-II, and cis-IV · dichloromethane are determined by XRD (CIF files CCDC nos. 2368769 (cis-II · chloroform), 2368770 (trans-II), and 2368771 (cis-IV · chloroform)). The platinum(II) dibromide complexes can crystallize as both cis and trans isomers. The study of the photophysical properties of the platinum(II) complexes shows that the trans isomers are characterized by emission in the orange spectral range, whereas the cis isomers almost does not luminesce. 10-(Aryl)phenoxarsines and their platinum(II) complexes are tested to cytotoxicity against the M-HeLa and HuTu 80 human cancer cell lines and hepatocyte-like cells of the Сhang liver line.