LAUSR

Abstract Six mononuclear organotin(IV) complexes of two dithiocarbamato ligands, [Ph3SnL1] (1), [Bu2Sn(L1)2] (2), [Ph2Sn(L1)Cl] (3), [Ph2Sn(L1)2] (4), [Ph2Sn(L2)2] (5) and [Ph3Sn(L2)] (6) where L1 = thiomorpholine-4-carbodithiolate and L2 = 2,6-dimethylmorpholine-4-carbodithiolate have been synthesized in good yields. Both ligands and complexes 1–6 were characterized by elemental analyses, FT-IR spectroscopy, UV-visible spectroscopy and 1H, 13C{1H} 119Sn{1H} NMR spectroscopy. In addition, the solid-state structures of the complexes were established through single-crystal X-ray diffraction analyses. The X-ray analyses reveal that the Sn(IV) center is five-coordinated in 1, 3 and 6. In complexes 2, 4 and 5, Sn(IV) is six-coordinated and occupies the center of a distorted octahedron. Moreover, an asymmetric coordination mode of the dithiocarbamato ligands was observed in all complexes. The optical properties and thermal stabilities of all complexes were investigated. All complexes were evaluated for their in vitro antimicrobial properties against E. coli. Complex 1 shows a maximal biological activity whereas the least activity is found for complex 6.