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The synthesis of five new complexes involving the ephedrinedithiocarbamate ligand (ephedtc) with group 13 and 15 metals (III) is reported. Complexes [As(ephedtc) 3 ] ( 1 ), [Sb(ephedtc) 3 ] ( 2 ), [Bi(ephedtc) 3 ] ( 3 ), and [In(ephedtc) 3 ] ( 5) were obtained from the ephedrinedithiocarbamate sodium salt [Na(ephedtc)] and the corresponding trichlorides MCl 3 , whereas for [Ga(ephedtc) 3 ], ( 4 ) Ga(NO 3 ) 3 was used. All compounds were characterized by elemental analyses, IR, mass spectrometry (FAB + ) and 1 H and 13 C NMR. In addition, single crystal structures of 2 and 5 were obtained showing two different coordination modes for the dithiocarbamate moiety, an anisobidentate coordination mode for 2 and an isobidentate coordination for 5 that generates a propeller-type structure. Compound 2 shows a distorted trigonal antiprismatic geometry around the metal atom while in 5 a distorted octahedral geometry is observed. Additionally, the crystalline structure of the ionic pair [ephedrinium] [ephedrinedithiocarbamate] ( 6 ) was determined. Antibacterial assay showed that 5 was the most active against ATCC bacterial strains and clinical isolate E. coli BLE (MIC 14.6–29.9 µM), and 3 against MRS strains (MIC 1.7 and 13.4 µM). The chemical hardness concept and the location of the HOMO and LUMO frontier orbitals on the molecular structures of 1 – 5 were employed to explain its particular antibacterial activity, using the DFT calculations.

Four new stibocanes substituted with cyclic dithiophosphate ligands O(CH2CH2S)2SbS2P(OCH2)2CEt2 (1), O(CH2CH2S)2SbS2P(OCH2)2C(Me)Pr (2), S(CH2CH2S)2SbS2P(OCH2)2CEt2 (3) and S(CH2CH2S)2SbS2P(OCH2)2C(Me)Pr (4) were prepared from the corresponding chloro oxa- and thia-stibocanes and the sodium salt of the dithiophosphoric acids 5,5-diethyl-(2-mercapto-2-thiono-1,3,2-dioxaphosphinane) and 5-methyl-5-propyl-(2-mercapto-2-thiono-1,3,2-dioxaphosphinane) in ethanol. The compounds obtained were characterized by IR, EI-MS and multinuclear NMR (1H, 13C, 31P) spectroscopies. The single-crystal structures of 1 and 2 were determined which show the presence of three types of secondary bonding: i.e. strong Sb- - -O transannular interactions of 2.607(4) and 2.600(4) A, respectively, anisobidentate coordination of the ligand (exocyclic chelation) average Sb- - -S distance 3.355 A and intermolecular interactions that lead to supramolecular associations. The coordination geometry around antimony atom in both 1 and 2 can be described as Ψ tricapped trigonal bipyramidal AB4CD2E. The eight membered ring presents a boat-chair conformation in both compounds and the 1,3,2-dioxaphosphinane ring has the chair conformation, with the stibocane in the axial position.

Five new chlorodiorganotin(IV) complexes derived from dithiocarbamate ligands have been prepared and structurally characterized. The complexes 1–5 with the general formula {(Ph2SnCl)dtc} (dtc = R1R2NCS2−; 1, R1 = Bn, R2 = 9-anthrylmethyl; 2, R1 = Bn, R2 = 9-phenanthrylmethyl; 3, R1 = Bn, R2 = 1-pyrenylmethyl; 4, R1 = 1-naphthylmethyl, R2 = 1-pyrenylmethyl; 5, R1 = R2 = 1-pyrenylmethyl) have been obtained from Ph2SnCl2 and the sodium dithiocarbamate salts of benzyl(9-anthrylmethyl)amine, benzyl(9-phenanthrylmethyl)amine, benzyl(1-pyrenylmethyl)amine, 1-naphthylmethyl(1-pyrenylmethyl)amine and di(1-pyrenylmethyl)amine. Compounds 1–5 have been analyzed as far as possible by elemental analysis, FAB+ mass spectrometry, IR, UV–Vis, fluorescence and NMR (1H, 13C, 119Sn) spectroscopy, and single-crystal X-ray diffraction analysis (1–3). The solid-state and solution studies showed that the dtc ligands are coordinated to the tin atoms in the anisobidentate manner. In all cases the metal centers are five-coordinate. The coordination geometry is intermediate between square-pyramidal and trigonal-bipyramidal coordination polyhedra with τ-values in the range of 0.49–0.55. The crystal structures show the presence of C–H···Cl, C–H···S, C–H···π, offset π–π and S···π contacts. The stability of the (Ph2SnCl)dtc complexes in the presence of the acetate anion has been examined in acetonitrile solutions. For all of these organotin(IV) complexes the displacement of the coordinated ligands (i.e., chloride and dtc) by the acetate anion was observed. The lability, as well as their intrinsic fluorescent properties of the polyaromatic moieties in these (Ph2SnCl)dtc compounds make them interesting candidates to detect the presence of O-donor anions at very low concentrations by displacement of the metal-coordinated dtc.

One dinuclear chlorodiphenyltin (IV) dithiocarbamate complex (1) and four mononuclear complexes of general formula Ph2Sn(S2CNR)Cl (2, 3, 5, and 6) have been synthesized and characterized both in solidstate and solution. X-ray structures for complexes 1, 3 and 6 demonstrated a five-coordination geometry around of tin atoms, in which dithiocarbamate ligand chelates asymmetrically the metal center. As shown by 119 Sn NMR spectroscopy, five-coordination geometry observed in the solid-state remains in solution. The stability of these chlorodiphenyltin(IV) dithiocarbamate complexes in the presence of biologically relevant anions such as acetate, dicarboxylates of general formula � OOC-(CH2)n-COO � (n = 2–8), dihydrogenphosphate, hydrogensulfate, and halides has been examined in acetonitrile solutions. For all of these organotin(IV) complexes the displacement of the coordinated ligands (i.e., chloride and dithiocarbamate) from the organotin(IV) moiety occurred in the presence of monoanions like acetate, dihydrogenphosphate, hydrogensulfate and fluoride. A stepwise mechanism for ligand exchange is proposed based on UV–Vis, 1