Thiosaccharinate Anion Research Articles

Structure and toxicity of N-donor thionate Zn complexes

The reaction of thiosaccharin (thiosaccharin: the thione form of saccharin) and N-donor bases with Zn2+ yielded three new thionate complexes: [Zn(tsac)2(imidazole)2], [Zn(tsac)2(benzimidazole)2]·H2O and [Zn(tsac)2(2-methylimidazole)2]·2 H2O (tsac: thiosaccharinate, C6H4C(S)NSO2). The new complexes were characterized employing Fourier Transform Infrared Spectroscopy (FTIR) and elemental analysis (EA). [Zn(tsac)2(imidazole)2] and [Zn(tsac)2(benzimidazole)2]·H2O crystal structures were determined with the aid of single crystal X-ray diffraction analysis (XRD). Both complexes exhibit a tetrahedral S2N2Zn environment, with the thiosaccharinate anions coordinated through their exocyclic Sulphur atoms. The structure of [Zn(tsac)2(2-methylimidazole)2]·2 H2O was proposed based on spectroscopic analysis.Moreover, a study on the effects of the three coordination compounds on erythrocyte sedimentation rate and osmotic fragility of red blood cells were held. Results revealed that these compounds at concentrations up to 10 μg/mL do not affect the activity of pro-sedimentation and anti-sedimentation factors. Only [Zn(tsac)2(2-methylimidazole)2]·2 H2O at 10 μg/mL induced fragility on red blood cells membrane.

Ni-thiosaccharinate complexes: Synthesis, characterization and DFT studies. Biological properties as superoxide dismutase mimetics and as anti-carcinogenic agents

This report describes the synthesis and characterization of two nickel thiosaccharinate complexes, [Ni(tsac)2(PPh3)2] (1) and [Ni(tsac)2(dppe)]·CH3CN (2), where tsac = thiosaccharinate anion, PPh3 = triphenylphosphane and dppe = bis(diphenylphosphanyl)ethane. Elemental analysis, FTIR, 1H, 13C and 31P NMR spectra and single crystal X ray diffraction studies of the complexes are presented. DFT optimizations of the two new compounds were performed in order to verify the FTIR vibrational assignations. The two nickel(II) thiosaccharinate complexes consist of mononuclear units in which the Ni atoms are the centre of square-planar coordination spheres, surrounded by two sulfur thiosaccharinate atoms and two phosphorous atoms from the phosphane ligands. In both complexes, the anions are mono-coordinated to the metal. In the [Ni(tsac)2(PPh3)2] structure, the phosphane moieties are located in trans position. In the [Ni(tsac)2(dppe)] structure, the dppe ligand chelates to the metal centre, as expected. Additionally, the superoxide dismutase (SOD) mimetic activity of the complexes was measured and it is reported herein. The effects of the complexes on cell proliferation were also studied and are described.

Three new Ag(I) thiosaccharinate complexes: Synthesis, structural studies, spectral characterization and theoretical analysis

Three silver thiosaccharinate complexes, two of them with diverse coordination geometries controlled by the ancillary nitrogen donor ligands are presented. The dinuclear silver thiosaccharinate complex, catena-poly-[Ag2(tsac)2]·C3H7NO (1·DMF), (thiosaccharinate=thiosaccharinate anion, DMF=dimethylformamide) in the crystalline state is a one dimensional coordination polymer bridged by the thiosaccharinate ligand with a very short silver–silver distance, 2.8930(16)Å. The biquinoline silver(I) thiosaccharinate, [Ag(tsac)(2,2′-bquin)]·CH3CN (2·CH3CN), (bquin=2,2′-biquinoline) in the crystalline state consists of a mononuclear neutral unit solvated with an acetonitrile molecule. The double complex salt, [Ag(2,4,6-coll)2][Ag(tsac)2] (3), (2,4,6-coll=2,4,6-collidine) possesses a very unusual arrangement for a silver thiosaccharinate, one similar to an ionic silver-pyridine based structure. The complex cation is formed by two 2,4,6-trimethylpyridine molecules coordinated to the silver atom while the complex anion is composed of two thiosaccharinate anions coordinated to the silver atom. In both cation and anion, the silver center has a linear geometry with the ligands planar. The syntheses, full characterizations and crystal structures of the three complexes are described. The structures of these newly synthesized silver(I) thiosaccharinate complexes have been optimized and their structural parameters have been calculated at the B3LYP/6-31G(2d,p)/LANL2DZ level of theory. The 13C NMR chemical shifts for the DMSO solution species of (2) and (3) were calculated using DFT/EPR-III/DZP first principles calculations with B3LYP, OLYP, OPBE, HCTH93 functionals.

An ethanol-solvated centrosymmetric dimer of bismuth(III) and thiosaccharinate resulting from `semicoordination' contacts.

In the title compound, bis(μ-1,1-dioxo-1,2-benzothiazole-3-thiolato)-κ(3)N,S:S;κ(3)S:N,S-bis[(1,1-dioxo-1,2-benzothiazole-3-thiolato-κ(2)N,S)(ethanol-κO)bismuth(III)] ethanol hemisolvate, [Bi2(C7H4NO2S2)6(C2H5OH)2]·0.5C2H5OH, three independent thiosaccharinate (tsac) anions chelate the metal centre through the endocyclic N and exocyclic S atoms. The complex also presnts two `semicoordination' contacts, one from a pendant ethanol solvent molecule and a second one from an S atom of a centrosymmetrically related molecule. This latter interaction complements two π-π interactions between tsac rings to form a dimeric entity which is the elemental unit that builds up the crystal structure. These dinuclear units are connected to each other via a second type of π-π interaction, generating chains along [111]. Two ethanol molecules, one of them of full occupancy at a general position and semicoordinated to the central cation, and a second one depleted and disordered around a symmetry centre, stabilize the structure. The complex was studied theoretically and the vibrational assignations were confirmed by employing theoretical density functional theory (DFT) methods.

Different coordination modes of the thiosaccharinate anion in dinuclear and one dimensional polymeric silver–azine complexes

The effect of substituted pyridines bases upon the coordination of thiosaccharinate (tsac, C 7H 4NO 2S 2 − in ternary silver complexes is analyzed. Four crystalline silver-substituted pyridine complexes with tsac as a coordinating counter anion, [Ag(tsac)(3-methylpyridine) 2] n , [Ag 2(tsac) 2(4-methylpyridine)] n , [Ag 2(tsac) 2(quinoline) 2] and [Ag(tsac)(4-methyloxypyridine)] n were synthesized and characterized by means of spectroscopic (IR and Raman, UV–Vis, and 1H and 13C NMR) and X-ray diffraction techniques. The thiosaccharinate anion showed its versatility coordinating to the metal in each complex by a different way. In the 3-Mepy complex it was coordinated in a μ 2-S mode and in the 4-MeOpy complex it was bound in a μ 3-S form both resulting in polymeric chains. In the 4-Mepy complex the anion was bound in a μ 2-S,N head to head mode and in the quinoline complex in a μ 2-S,N head to tail mode, both showing dinuclear arrangements.

Synthesis and Structural Analysis of New Palladium(II) Thiosaccharinates with Triphenylphosphane or Diphosphanes

AbstractA series of palladium(II) thiosaccharinates with triphenylphosphane (PPh3), bis(diphenylphosphanyl)methane (dppm), and bis(diphenylphosphanyl)ethane (dppe) have been prepared and characterized. From mixtures of thiosaccharin, Htsac, and palladium(II) acetylacetonate, Pd(acac)2, the palladium(II) thiosaccharinate, Pd(tsac)2 (tsac: thiosaccharinate anion) (1) was prepared. The reaction of 1 with PPh3, dppm, and dppe leads to the mononuclear species Pd(tsac)2(PPh3)2·MeCN (2), [Pd(tsac)2(dppm)] (3), Pd(tsac)2(dppm)2 (4), and [Pd(tsac)2(dppe)]·MeCN (5). Compounds 2, 4, and 5 have been prepared also by the reaction of Pd(acac)2 with the corresponding phosphane and Htsac. All the new complexes have been characterized by chemical analysis, UV/Vis, IR, and Raman spectroscopy. Some of them have been also characterized by NMR spectroscopy. The crystalline structures of complexes 3, and 5 have been studied by X‐ray diffraction techniques. Complex 3 crystallizes in the monoclinic space group P21/n with a = 16.3537(2), b = 13.3981(3), c = 35.2277(7) Å, β = 91.284(1)°, and Z = 8 molecules per unit cell, and complex 5 in P21/n with a = 10.6445(8), b = 26.412(3), c = 15.781(2) Å, β = 107.996(7)°, and Z = 4. In compounds 3 and 5, the palladium ions are in a distorted square planar environment. They are closely related, having two sulfur atoms of two thiosaccharinate anions, and two phosphorus atoms of one molecule of dppm or dppe, respectively, bonded to the PdII atom. The molecular structure of complex 3 is the first reported for a mononuclear PdII‐dppm‐thionate system.

Four novel mononuclear and polynuclear Cu(I) thiosaccharinates with triphenylphosphane and bis(diphenylposphino)methane. Synthesis and structural study of Cu 4(tsac) 4(PPh 3) 3, Cu(tsac)(PPh 3) 2, Cu 4(tsac) 4(dppm) 2, and Cu 2(tsac) 2(dppm) 2

Four new ternary complexes of copper(I) with thiosaccharin and phosphanes were prepared. The reaction of [Cu 4(tsac) 4(CH 3CN) 2] ( 1) (tsac: thiosaccharinate anion) with PPh 3 in molar ratios Cu(I)/PPh 3 1:075 and 1:2 gave the complexes [Cu 4(tsac) 4(PPh 3) 3] · CH 3CN ( 2) and Cu(tsac)(PPh 3) 2 ( 3), respectively. The reaction of 1 with Ph 2PCH 2PPh 2 (dppm) in molar ratios Cu(I)/dppm 2:1 and 1:1 gave the complexes [Cu 4(tsac) 4(dppm) 2] · 2CH 2Cl 2 ( 4) and [Cu 2(tsac) 2(dppm) 2] · CH 2Cl 2 ( 5), respectively. All the compounds have been characterized by spectroscopic and X-ray crystallographic methods. Complex 2 presents a tetra-nuclear arrangement with three metal centers in distorted tetrahedral S 2NP environments, the fourth one with the Cu(I) ion in a distorted trigonal S 2N coordination sphere, and the tsac anions acting as six electron donor ligands in μ 3-S 2N coordination forms. Complex 3 shows mononuclear molecular units with copper(I) in a distorted trigonal planar coordination sphere, built with the exocyclic S atom of a mono-coordinated thiosaccharinate anion and two P-atoms of triphenylphosphane molecules. With dppm as secondary ligand the structures of the complexes depends strongly on the stoicheometry of the preparation reaction. Complex 4 has a centrosymmetric structure. Two triply bridged Cu 2(tsac) 2(dppm) units are joined together by the exocyclic S-atoms of two tsac anions acting effectively as bridging tridentate ligands. Complex 5 is conformed by asymmetric dinuclear moieties where the two dppm and one tsac ligands bridge two Cu(I) atoms and the second tsac anion binds one of the metal centers through its exocyclic S-atom.

A New Supramolecular Assembly Obtained by Reaction Between Thiosaccharin and Pyridine

The crystal structure of pyridinium thiosaccharinate thiosaccharin, [HNC5H5]+ [(tsac)(Htsac)]− (Htsac = C7H5NO2S2, the thiosaccharin molecule), was determined by single-crystal X-ray diffraction. Both, the thiosaccharinate anion, the corresponding neutral molecule and the pyridinium cation are nearly planar and arranged in the solid state in an almost parallel fashion, hence giving rise to a layered supramolecular structure. The anion shows small but significant modifications in the bonding of the thioamide group as compared with the neutral molecule. The crystal is further stabilized by an extensive H-bonding network. The FTIR spectrum of the compound is briefly commented.

Unusual coordination in a silver thionate complex. Synthesis, structural characterization and theoretical calculations of dinuclear and polynuclear silver(I) thiosaccharinates with pyridine and 1,10-phenanthroline

Treatment of Ag 6(tsac) 6 (tsac = thiosaccharinate anion) with pyridine (py) and 1,10-phenanthroline ( o-phen) each affords two novel silver(I)-thiosaccharinate complexes: dinuclear [Ag 2(tsac) 2py] ( 1) and polynuclear [Ag(tsac)( o-phen)] n ( 2). Both crystal structures have been determined by X-ray diffraction and spectroscopic structural analysis (IR and Raman, UV–Vis, 1H and 13C NMR) have also been made for both compounds. Thermal stability analysis (TGA and DTA) of complex 1 are used to confirm the strength of the pyridine coordination to the silver ion. The molecular structure of complex 1 shows some astonishing characteristics. The two silver atoms are in different environments: one of them is surrounded by two S atoms, while the other completes its coordination sphere by three N atoms, two from the thiosaccharinate anions and the third from a pyridine molecule. The short Ag(1)–Ag(2) contact distance, 2.9681(8) Å, indicates an interaction between the two silver metal atoms exists. Complex 2 shows a thiosaccharinate molecule bridging two silver atoms through the exocyclic S atom while the o-phenanthroline ligand is coordinated as a bidentate N, N chelate, forming a polynuclear chain. Quantum chemical calculations confirm the argentophilic character of the Ag–Ag interaction in complex 1, and its structure and vibrational assignments were correlated and confirmed theoretically.

Mono and Poly-nuclear Silver(I) Complexes with Thiosaccharin and Triphenylphosphine. Synthesis, Spectroscopic and Structural Characterization of Thiosaccharinato-bis(triphenylphosphine)silver(I) and Tetrakis{thiosaccharinato(triphenylphosphine)silver(I)}

The reaction of Ag6(tsac)6 (1) (tsac = thiosaccharinate anion) with triphenylphosphine gives rise to the already reported [Ag(tsac)(PPh3)3] complex (2) and to two new silver-thiosaccharinate-phosphine complexes, [Ag(tsac)(PPh3)2] (3) and [Ag4(tsac)4(PPh3)4] (4) (PPh3= triphenylphosphine). Spectroscopic characterization was carried out using IR, UV-Visible and NMR techniques and confirmed by single crystal X-ray diffraction. In each complex a singular coordination mode for the thiosaccharinate ligand is observed. The most important features of the different coordination modes of the thionates are discussed. Compound 3 crystallizes in monoclinic system, space group Pn, with a = 11.2293(3) Å, b = 12.7282(3) Å, c = 13.6056(4) Å, β = 94.985(2)°, Z = 2; while crystals of compound 4 are monoclinic, space group P21/n, a = 15.024(3) Å, b = 14.681(3) Å, c = 21.914(4) Å, β = 95.31(3)°, Z = 2. The coordination around the silver atoms in both complexes consists of almost trigonal-planar arrangements, AgP2S in 3 and AgS2P in 4.

Synthesis and Spectroscopic Characterization of Two New Thiosaccharinate Salts. Molecular Structure of Bis(triphenylphosphine)iminium thiosaccharinate, PNP(tsac)

We report the synthesis, FTIR, Raman and NMR spectroscopic features of bis(triphenylphosphine)iminium and tetrabutylammonium thiosaccharinates, PNP(tsac) and NBu4(tsac) (tsac: thiosaccharinate anion, PNP: bis(triphenylphosphine)iminium). The molecular structure of the former compound was determined by X-ray diffraction methods. The salt crystallizes in the monoclinic P21/n space group with a = 9.6481(9), b = 29.258(3), c = 13.177(2) A, β = 97.53(1)°, and Z = 4 molecules per unit cell. Slight but significant changes in the bonding structure of the thiosaccharinate anion as compared with those reported for the neutral molecule are observed.

Synthesis and Spectroscopic Characterization of New Lead(II) Thiosaccharinates. Molecular Structure of Bis(thiosaccharinato)tetrakis(pyridine)dilead(II) and Thiosaccharinato‐bis(1,10‐phenantroline)lead(II) Thiosaccharinate

AbstractFour new lead(II) thiosaccharinate complexes: [Pb(tsac)2H2O] (1) (tsac: thiosaccharinate anion), [Pb2(tsac)4(py)4] (2) (py: pyridine), [Pb(tsac)(o‐phen)2](tsac)·CH3CN (3) (o‐phen: 1,10‐phenantroline), and [Pb(tsac)2(bipy)] (4) (bipy: 2,2′‐bipyridine) were prepared. The infrared and electronic spectra as well as the thermal analysis of all the compounds were recorded and discussed. The thiosaccharinate anion acts in three different coordination forms, one of then reported for the first time. The crystal structures of complexes 2 and 3 have been determined by single crystal X‐ray diffractometry. In complex 2, two monomeric moieties are joined together forming a symmetric bis‐μ‐sulphur bridged dimer by interaction of two lead(II) atoms through the exocyclic sulphur atoms of two thiosaccharinate ligands. The seven‐fold coordination sphere of each lead atom is completed by two pyridine nitrogen atoms and by another sulfur and two nitrogen atoms of the thiosaccharinate anions. In complex 3, the lead(II) atom is coordinated by four nitrogen atoms of two 1,10‐phenantroline molecules and by the sulfur and nitrogen atoms of one thiosaccharinate ion. The second anion has an electrostatic interaction with the nucleus.

Mono and polynuclear silver(I) complexes with thiosaccharine and triphenylphosphine or 2,2′-bipyridine. Synthesis, spectroscopic and structural characterization

Reaction of Ag 6(tsac) 6 (tsac − = thiosaccharinate anion) with PPh 3 and 2,2′-bipyridine (bipy) ligands give rise to three new silver-thiosaccharinate complexes, [Ag(tsac)(PPh 3) 3], [Ag 4(tsac) 4(PPh 3) 3] , and [Ag 2(tsac) 2(bipy) 2]. Their crystal structures established by single-crystal X-ray diffraction and IR spectroscopic characterizations are reported here. In each complex a singular coordination mode for the thiosaccharinate ligands is observed. The most important features of the different coordination modes of the thionates are discussed.

Structural and spectroscopic characterization of bis(thiosaccharinato)bis(benzimidazole)cadmium(II)

The crystal structure of [Cd(tsac) 2(bzim) 2]·CH 3OH (tsac, anion of thiosaccharine; bzim, benzimidazole) has been determined by single crystal X-ray diffractometry. It crystallizes in the triclinic space group P 1 ¯ with Z = 2. The Cd(II) cation is in a distorted tetrahedral environment coordinated to two thiosaccharinate anions [Cd–S bond lengths of 2.5117(6) and 2.5598(6) Å] and two benzimidazole molecules [Cd–N lengths of 2.235(2) and 2.256(2) Å]. The FTIR spectrum of the complex is also recorded and briefly discussed. Some comparisons with related complexes are made.

Vibrational analysis of thiosaccharin and thiosaccharinate anion. A gradient-corrected density functional and experimental study

A gradient-corrected density functional (DFT) study of thiosaccharin molecule and of the corresponding nitranion was carried out using various combinations of exchange and correlation functionals, with a special emphasis on the vibrational analysis of the studied species. The employed DFT methodologies included the B3LYP, mPW1PW91, HCTH and the OLYP combinations of functionals, using the 6-31+G(d,p) basis set for orbital expansion in solving the Kohn–Sham SCF equations. Full geometry optimizations of thiosaccharin molecule and the corresponding nitranion were carried out employing Schlegel's gradient optimization algorithm. Subsequently, harmonic vibrational analyses were carried out for the minima located on the corresponding molecular/ionic potential energy hypersurfaces. Also, Fourier transform infrared (FT IR) spectra of thiosaccharin and a series of metal thiosaccharinates (those of Na, K, Mg, Mn, Co, Ni, Cu, Zn, Cd, Hg and Pb) were recorded at room and liquid nitrogen boiling temperature. Experimental FT IR vibrational spectra of the studied systems were analyzed in the light of the computed density functional harmonic force fields for free thiosaccharin molecule and its nitranion. The performances of various DFT methodologies employed were compared.

Structural and Spectroscopic Characterization of Two New Thallium(I)/Thiosaccharinate Complexes

AbstractThe crystal structures of [Tl(tsac)] (1) and [Tl(tsac)(ophen)] (2) (tsac = anion of thiosaccharin; ophen = 1, 10 phenanthroline) have been determined at 116 K by single crystal X‐ray diffractometry. Complex 1 crystallizes in the monoclinic space group P21/a with Z = 4 and complex 2 in the monoclinic space group C2/c with Z = 8.In both complexes TI is coordinated to a thiosaccharinate anion through its sulphur and nitrogen atoms. A distorted eight fold coordination sphere around the cation in complex 1 is completed with two other longer Tl‐S bonds and four Tl···O contacts with five symmetry related neighbouring thiosaccharinate anions. A phenanthroline molecule acting as a bidentate ligand through its nitrogen atoms completes a four‐fold coordination around the metal atom in complex 2. The infrared spectra of both complexes were also recorded and their most important features discussed on the basis of its structural peculiarities.