Synthesis, X-ray structures, spectroscopic analysis and anticancer activity of novel gold(I) carbene complexes

Three new linear gold(I) complexes of the formulas [(Ipr)Au(S2CN(CH3)2)] (1), [(Ipr)Au (S2CN(C2H5)2)] (2) and [(Ipr)Au(S2CN(C7H7)2)] (3) [where Ipr = 1,3-bis(2,6-di-isopropylphenyl)imidazol-2-ylidenegold] have been prepared by the reaction of equimolar amounts of 1,3–bis(2,6-di-isopropylphenyl)imidazol-2-ylidenegold(I)chloride, [(Ipr)Au(Cl)] with sodium dimethyldithiocarbamate monohydrate, sodium diethyl dithiocarbamatetrihydrate and dibenzyl dithiocarbamate, respectively. The structures of the complexes have been determined by single X-ray crystallography. All gold(I) complexes (1–3) are iso-structural i.e. linear geometry. The complex (1) crystallizes in monoclinic space group ‘P21/a’, while the complexes (2) and (3) crystallize in orthorhombic space group ‘Pna21’. The IR spectra and 1H as well as 13C NMR measurements of the Au(I) complexes (1–3) corroborate well with their single crystal X-ray structure analysis. These gold(I) complexes show moderate potential anti-cancer activities against A549 (human lung carcinoma), HCT15 (human colon cancer), and HeLa (human cervical cancer) cell lines.