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We present the first example of a silver double-tetranuclear cluster helicate [Ag4L2]2 obtained from a bisthiosemicarbazone ligand using electrochemical synthesis. This cluster helicate undergoes a rare desulfurization process in chloroform giving rise to a cationic silver dihelicate [Ag2(H2L)2]SO4. This is the first silver mediated desulfurization reaction., FEDER cofunded-grants: from Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia, 2017 GRC GI-1682 (ED431C 2017/01), 2018 GRC GI-1584 (ED431C 2018/13), MetalBIO Network (ED431D 2017/01), Ministerio de Ciencia, Innovación y Universidades, METALBIO (CTQ2017-90802-REDT) and MultiMetDrugs (RED2018-102471-T).

The coordination of metal ions to a carbamate ligand triggers its hydrolysis, which ends up in self-immolation of the complex releasing new metal species, a pendant molecule (A) and CO2.

Hoxe en día, a Física e a Química enténdense como parte ou porción de algo máis grande que denominamos Ciencias. Neste senso, concíbese ciencia como “unha parte importante da nosa cultura porque ofrece un conxunto de historias explicativas substantivas que nos contan cousas novas importantes e interesantes sobre nós mesmos e sobre o mundo no que vivimos, cousas que demostraron ser perfectamente fiables e útiles”. Isto non debe ser entendido no sentido de que a ciencia ten un valor de autoridade absoluta en canto ao coñecemento da realidade do mundo que nos rodea. Máis ben, a ciencia debe ser entendida como un compendio de coñecemento baseado na observación, que nos ofrece unha realidade novidosa e sorprendente que se encontra lonxe, na maioría de ocasións, do que parece ser algo de modo inmediato, e na cal se pode confiar, tanto para actuar no noso día a día, como para desenvolver avances científicos ou tecnolóxicos que melloren a nosa vida. Ninguén dubida da necesidade de transmitir estes coñecementos científicos ás novas xeracións e que estas sexan quen de adquirilos de forma axeitada. Neste sentido, débese destacar o papel clave que vai xogar a escola, entendida como o principal axente responsable da reprodución cultural e, en consecuencia, da ciencia.

Complexes trans,trans,trans-[Pt(N3)2(OH)(OCOR)(py)2] where py = pyridine and where OCOR = succinate (1); 4-oxo-4-propoxybutanoate (2) and N-methylisatoate (3) have been synthesized by derivation of trans,trans,trans-[Pt(OH)2(N3)2(py)2] (4) and characterised by NMR and EPR spectroscopy, ESI-MS and X-ray crystallography. Irradiation of 1–3 with green (517 nm) light initiated photoreduction to Pt(ii) and release of the axial ligands at a 3-fold faster rate than for 4. TD-DFT calculations showed dissociative transitions at longer wavelengths for 1 compared to 4. Complexes 1 and 2 showed greater photocytotoxicity than 4 when irradiated with 420 nm light (A2780 cell line IC50 values: 2.7 and 3.7 μM) and complex 2 was particularly active towards the cisplatin-resistant cell line A2780cis (IC50 3.7 μM). Unlike 4, complexes 1–3 were phototoxic under green light irradiation (517 nm), with minimal toxicity in the dark. A pKa(H2O) of 5.13 for the free carboxylate group was determined for 1, corresponding to an overall negative charge during biological experiments, which crucially, did not appear to impede cellular accumulation and photocytotoxicity., Axially-derived platinum(iv) diazido dihydroxido complexes retain dark stability with rapid photoreduction under irradiation with green (517 ± 27 nm) light. Cell uptake is unhindered by overall negative charge at physiological pH (complex 1).

The effect of the ligand and/or metal-related factors on the formation of tristhiosemicarbazone metallosupramolecular complexes has been studied in this work. The crystal structures of zinc(II) and lead(II) tristhiosemicarbazone mesocates and a hydrolyzed cadmium(II) helicate let us better rationalize some factors involved in the selective formation of helicates or mesocates.

In this work, four manganese(II) complexes derived from the ligands H2L1-H2L4, that incorporate dansyl or tosyl fluorescent dyes, have been investigated in term of their antioxidant properties. Two of the manganese(II) complexes have been newly prepared using the asymmetric half-salen ligand H2L2 and the thiosemicarbazone ligand H2L3. The four organic strands and the manganese complexes have been characterized by different analytical and spectroscopic techniques. The study of the antioxidant behaviour of these two new complexes and other two fluorophore-labelled analogues was tested in SH-SY5Y neuroblastoma cells. These four model complexes 1–4 were found to protect cells from oxidative damage in this human neuronal model, by reducing the release of reactive oxygen species. Complexes 1–4 significantly improved cell survival, with levels between 79.1 ± 0.8% and 130.9 ± 4.1%. Moreover, complexes 3 and 4 were able to restore the mitochondrial membrane potential at 1 μM, with 4 reaching levels higher than 85%, similar to the percentages obtained by the positive control agent cyclosporin A. The incorporation of the fluorescent label in the complexes allowed the study of their ability to enter the human neuroblastoma cells by confocal microscopy The research leading to these results has received funding from the following FEDER cofunded-grants. From Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia, 2017 GRC GI-1682 (ED431C 2017/01), 2018 GRC GI-1584 (ED431C 2018/13), MetalBIO Network (ED431D 2017/01). From CDTI and Technological Funds, supported by Ministerio de Economía, Industria y Competitividad IISCIII/PI19/001248. From Ministerio de Ciencia, Innovación y Universidades, MULTIMETDRUGS (RED2018-102471-T). From European Union, Interreg AlertoxNet EAPA-317-2016, Interreg Agritox EAPA-998-2018, and H2020 778069-EMERTOX SI

A dinuclear Pb(ii) mesocate has been prepared with an unprecedented four-coordinated kernel in which the Pb(ii) lone pair is stereochemically active. This is the first time that this effect has been observed in a supramolecular Pb(ii) helicate or meso-helicate.

The lectin DLasiL was isolated from seeds of the Dioclea lasiocarpa collected from the northeast coast of Brazil and characterized for the first time by mass spectrometry, DNA sequencing, inductively coupled plasma-mass spectrometry, electron paramagnetic resonance, and fluorescence spectroscopy. The structure of DLasiL lectin obtained by homology modelling suggested strong conservation of the dinuclear Ca/Mn and sugar-binding sites, and dependence of the solvent accessibility of tryptophan-88 on the oligomerisation state of the protein. DLasiL showed highly potent (low nanomolar) antiproliferative activity against several human carcinoma cell lines including A2780 (ovarian), A549 (lung), MCF-7 (breast) and PC3 (prostate), and was as, or more, potent than the lectins ConBr (Canavalia brasiliensis), ConM (Canavalia maritima) and DSclerL (Dioclea sclerocarpa) against A2780 and PC3 cells. Interestingly, DLasiL lectin caused a G2/M arrest in A2780 cells after 24 h exposure, activating caspase 9 and delaying the on-set of apoptosis. Confocal microscopy showed that fluorescently-labelled DLasiL localized around the nuclei of A2780 cells at lectin doses of 0.5–2 × IC50 and gave rise to enlarged nuclei and spreading of the cells at high doses. These data reveal the interesting antiproliferative activity of DLasiL lectin, and suggest that further investigations to explore the potential of DLasiL as a new anticancer agent are warranted.\ud

The effect of the metal ion and ligand design on the enantioselectivity and linkage isomerization of neutral cobalt and zinc bisthiosemicarbazone metallohelicates has been investigated in this work. The electrochemical synthesis has afforded the enantioselective formation of chirally pure cobalt helicates, and the ΛΛ isomer of a single enantiomer has been crystallized as only product for the cobalt methyl-substituted thiosemicarbazone helicate. Interestingly linkage isomers have been formed from zinc ethyl-substituted thiosemicarbazone helicate enantiomers for the first time. The co-existence of these isomers has been evaluated from the point of view of both experimental results and computational calculations.

We report the synthesis and characterization of a symmetric [N4] tetradentate imine-type ligand H2L that incorporates a dansyl fluorophore group in both ligand arms. Two binding domains separated by a short arene spacer and two bulky arms with an anti conformation make this organic molecule suitable as precursor of metallosupramolecular species such as helicates. The molecular structure of H2L has been analyzed by X-ray diffraction. This technique has revealed the formation of intermolecular hydrogen bond interactions that lead to the supramolecular self-assembly of ligand molecules in the solid state and the generation of oval-shaped channels in the 3D crystal packing.

Gold compounds to be obtained by the direct electrochemical oxidation of a noble metal are reported. This achievement provides an alternative procedure to obtaining neutral gold compounds with potential medical or catalytic applications.

Dinuclear trihydroxido‐bridged osmium–arene complexes are inert and biologically inactive, but we show here that linking dihydroxido‐bridged OsII–arene fragments by a bridging di‐imine to form a metallacycle framework results in strong antiproliferative activity towards cancer cells and distinctive knotting of DNA. The shortened spacer length reduces biological activity and stability in solution towards decomposition to biologically inactive dimers. Significant differences in behavior toward plasmid DNA condensation are correlated with biological activity.

Some of the largest improvements in clinical outcomes for patients with solid cancers observed over the past 3 decades have been from concurrent treatment with chemotherapy and radiotherapy (RT). The lethal effects of RT on cancer cells arise primarily from damage to DNA. Ruthenium (Ru) is a transition metal of the platinum group, with potentially less toxicity than platinum drugs. We postulated that ruthenium-arene complexes are radiosensitisers when used in combination with RT. We screened 14 ruthenium-arene complexes and identified AH54 and AH63 as supra-additive radiosensitisers by clonogenic survival assays and isobologram analyses. Both complexes displayed facial chirality. At clinically relevant doses of RT, radiosensitisation of cancer cells by AH54 and AH63 was p53-dependent. Radiation enhancement ratios for 5–10 micromolar drug concentrations ranged from 1.19 to 1.82. In p53-wildtype cells, both drugs induced significant G2 cell cycle arrest and apoptosis. Colorectal cancer cells deficient in DNA damage repair proteins, EME1 and MUS81, were significantly more sensitive to both agents. Both drugs were active in cancer cell lines displaying acquired resistance to oxaliplatin or cisplatin. Our findings broaden the potential scope for these drugs for use in cancer therapy, including combination with radiotherapy to treat colorectal cancer.

A [4+4] double-stranded cadmium dihelicate was afforded from an easily accessible thiosemicarbazone ligand; its crystal structure reveals the assembly of two enantiomers into dihelicate pairs, these pairs being further connected into infinite linear chains.

The aim of the work described here was to test the general applicability of our recently reported route to cluster helicates and to carry out a systematic study to relate the structural and coordinative properties of the organic strands with the microarchitectures of the resulting cluster helicates. Nine new ZnII, CuI and AgI complexes were prepared from three Schiff base ligands [H2La: bis(4-methyl-3-thiosemicarbazone)-2,6-diacetylpyridine; H2Lb: bis(4-methyl-3-thiosemicarbazone)-2,6-diacetylbenzene; H2Lc: bis(4-ethyl-3-thiosemicarbazone)-2,6-diacetylbenzene]. The experimental data confirm that AgI and CuI tetranuclear cluster helicates were obtained with a [M4(Lx)2] stoichiometry, and this finding demonstrates the general applicability of the synthetic route. The cluster helicates presented in this work were characterized for the first time in solution by NMR spectroscopy. In addition, six of the nine complexes were characterized by X-ray diffraction studies, and three of them were found to be tetranuclear cluster helicates. A detailed study of these three crystal structures leads us to state that the changes introduced in the organic strands do not prevent the assembly of the tetranuclear cluster dihelicates, but they do affect the microarchitectures. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The interaction of the transition and post-transition metals manganese, iron, cobalt, nickel, zinc, cadmium and lead, with the ligand 4-N-methylthiosemicarbazone-2-pyridinecarboxaldehyde (HL) through an electrochemical procedure has been investigated. The novel complexes obtained via this synthetic route have the general formulae [M(L)2](H 2O)n (n = 1-3.5). The crystal and molecular structures have been determined for the mononuclear complexes [MnL2] ·H2O (2), [CoL2] (5), [NiL2] ·H2O (7) and [PbL2] (11). Complexes 2, 5 and 7 exhibit a distorted octahedral polyhedron around the metal atom, whilst the lead derivative shows a particular coordination polyhedron that may be regarded as a distorted bipyramidal pentagonal structure, with one apical position filled by the metal lone pair. All these complexes have been fully characterized by elemental analysis, infrared spectroscopy, mass spectrometry, magnetic and conductivity measurements, and 1H, 113Cd and 207Pb NMR techniques. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.

Densities and sound velocities of sodium perfluorohexanoate and sodium perfluorononanoate for different concentrations above and below the critical micelle concentration (cmc) have been obtained at different temperatures. Apparent molar volumes and compressibilities of the surfactants in the monomeric and micellar form have been estimated. The relevant results were plotted as a function of the temperature and the alkyl chain length by using previous data reported for sodium heptanoate and sodium octanoate. The expected linear behaviour in function of temperature and also alkyl chain length have been found. In order to analyze the influence of the substitution of the hydrogen by fluorine in the alkyl chain of the surfactant, the data were compared with the hydrogenated counterpart.

Four novel manganese(III) complexes have been prepared using the tetradentate ONNO symmetrical Schiff base N,N′‐(1,2‐phenylene)‐bis(3‐hydroxysalicylidenimine) H4L and employing different manganese(II) and manganese(III) starting salts (chloride, acetate, acetylacetonate and perchlorate). These complexes were thoroughly characterised by elemental analysis, ES mass spectrometry, infrared and paramagnetic 1H NMR spectroscopies, magnetic susceptibility measurements and molar conductivities. Electrochemical studies by cyclic and normal pulse voltammetry were also performed. All complexes obtained are manganese(III) ones, in which the anions belonging to the starting salts have diverse coordinating tendencies; this fact seems to determine the nuclearity of the final complexes, with empirical formulae [Mn(H2L)(H2O)2]Cl(H2O)3 1, [Mn(H2L)(OAc)](H2O) 2, [Mn(H2L)(acac)](H2O)3 3, and [Mn(H2L)(H2O)(CH3OH)](ClO4) 4. The X‐ray crystal structure of H4L Schiff base has been determined.

Sodium perfluoroalkyl carboxylates (C n FONa) with n = 6, 9, 10 have been studied by conductivity measurements at different temperatures. The Krafft point was determined for C9FONa and C10FONa at the highest concentration studied by measuring the temperature dependence of the specific conductivity. The critical micelle concentration (cmc) and the ionization degree of the micelle ( β ) were estimated from conductivity vs. molality plots at different temperatures. Using these data and previous results on temperature dependence of cmc and β of sodium perfluoroheptanoate and perfluorooctanoate, different models were applied to obtain the thermodynamic properties of micellization. The results are discussed in terms of alkyl chain length.

The electrochemical oxidation of a tin plate in the presence of an acetonitrile suspension of the ligand bis-(4-N-methylthiosemicarbazone)-2,6-diacetylpyridine, H4DAPTsz-Me, yields the complex Sn(H2DAPTsz-Me)(H2O)2 (1). Recrystallisation of 1 in a methanol/acetone solution leads us to isolate yellow crystals of [Sn(H2DAPTsz-Me)(CH3OH)2] · CH3OH (2), structurally characterised. To the best of our knowledge, 2 is the first neutral Sn(II) complex derived from a pentadentate thiosemicarbazone Schiff base ligand. This complex shows a distorted pentagonal bipyramidal geometry for Sn(II), being the metal surrounded by the N3S2 donor set of the bideprotonated ligand [H2DAPTsz-Me]2−. This compound self-assembles into a 3D network through intermolecular hydrogen bonds.

The copper complex of 2,6-bis(1-salicyloylhydrazonoethyl)pyridine, H4daps, has been prepared by an electrochemical procedure and characterised by elemental analysis, IR, FAB mass spectroscopy, ΛM, magnetic susceptibility measurements and EPR studies. The molecular structures of the ligand H4daps (1) and its copper complex [Cu(H2daps)(H2O)]2·2CH3CN (3) have been determined by X-ray diffraction studies. The ligand shows in the solid state a syn-open conformation that allows it to act as a binucleating ligand, after a conformational change, as is shown by the study of the copper dihelicate 3. This compound contains the dianionic ligand [H2daps]2− in an anti-open conformation. The comparative study of this complex, with others previously reported, allows us to confirm that the conformational rearrangement undergone by H4daps upon complexation depends strongly on the metal nature and its stereochemical preferences.

A cobalt(II) thiosemicarbazonate mesocate has been structurally characterized as an unexpected mixture of conformational and linkage isomers. Moreover, we have shown that the absence of a nitrogen atom in the spacer of the helicand ligand H(2)L(a), enables the assembly of an achiral mesohelical complex in the case of Co(II) ions.

We have studied the factors that affect the formation of different metallosupramolecular architectures by metal direct self-assembly. A synthetic route has been developed to obtain mesocates or dihelicates selectively. For this purpose a series of five bisthiosemicarbazone ligands derived from 1,3-diacetylbenzene were designed and synthesised. Namely H(2)L(Me), H(2)L(Et), H(2)L(Ph), H(2)L(PhN) and H(2)L(PhOMe) with different substituents on the 4-N terminal position of the thiosemicarbazone strands. The Co(II), Zn(II) and Cd(II) complexes of these ligands were prepared by an electrochemical procedure. Crystallographic studies revealed the formation of mesocates for Co(II) and Zn(II) metal ions whereas the Cd(II) complexes gave a bishelical supramolecular structure. Therefore these bisthiosemicarbazone ligands enable the selective isolation of mesocate or dihelicate complexes by using a specific metal ion.

The coordinative chemistry of the tridentate half-salen ligand 5-(dimethylamino)-N-(2-((2-hydroxybenzylidene)amino)phenyl)naphthalene-1-sulfonamide (H(2)L, 1) has been studied by means of an electrochemical method. All of the complexes have been characterised using analytical and spectroscopic techniques. Ligand 1 and two nickel (6 and 7), copper (9), zinc (12) and cadmium (14) metal complexes have been studied by crystallography. Complexes 6 and 7 are octahedral and tetrahedral nickel(II) complexes, respectively, and both contain an [L](2-) molecule that behaves in an [N(2)O] tridentate manner. Nickel(II) completes its coordination kernel with three water molecules in complex 6, whereas in complex 7 the nickel ion is further bound to a molecule of dansylamine arising from a hydrolysis process. The copper(II) complex 9 is a monomeric compound that contains a bideprotonated ligand thread and a dimethylsulfoxide molecule coordinated through the sulfur atom. The zinc complex 12 is an unusual pentanuclear cluster compound whose structure consists of four anionic ligand units and two hydroxo anions bound to five zinc(II) centres. The appearance of the hydroxo anions in this complex provides new evidence for water reduction electrochemically promoted by zinc metal under mild conditions. The cadmium complex 14 is a dimeric compound that comprises two molecules of the anionic ligand and two dimethylsulfoxide molecules. The great structural variety exhibited by all these complexes demonstrates that the introduction of asymmetry in a salen skeleton by incorporating a dansyl pendant increases the versatility of the resulting ligand on coordination. All complexes are luminescent in solution at room temperature in acetonitrile solutions.

A wide variety of steric and electronic features can be incorporated into transition metal coordination complexes, offering the prospect of rationally-designed therapeutic agents with novel mechanisms of action. Here we compare the chemical reactivity and anticancer activity of organometallic OsII complexes [Os(η6-arene)(XY)Z]PF6 where arene = p-cymene or biphenyl, XY = N,N′-chelated phenyliminopyridine or phenylazopyridine derivatives, and Z = Cl or I. The X-ray crystal structure of [Os(η6-p-cym)(Impy-OH)I]PF6·0.5CH2Cl2·H2O (Impy-OH = 4-[(2-pyridinylmethylene)amino]-phenol) is reported. Like the azopyridine complexes we reported recently (Dalton Trans., 2011, 40, 10553–10562), some iminopyridine complexes are also potently active towards cancer cells (nanomolar IC50 values). However we show that, unlike the azopyridine complexes, the iminopyridine complexes can undergo aquation, bind to the nucleobase guanine, and oxidize coenzyme nicotine adenine dinucleotide (NADH). We report the first detection of an Os-hydride adduct in aqueous solution by 1H NMR (−4.2 ppm). Active iminopyridine complexes induced a dramatic increase in the levels of reactive oxygen species (ROS) in A549 lung cancer cells. The anticancer activity may therefore involve interference in the redox signalling pathways in cancer cells by a novel mechanism.

We have prepared some transition and post-transition metal complexes derived from the pentadentate thiosemicarbazone ligand bis(4-N-ethylthiosemicarbazone)-2,6-diacetylpyridine H(2)L(Et), by both chemical and electrochemical procedures. The complexes have been synthesised and fully characterised, including the crystal structures for the ligand H(2)L(Et) and its manganese, cadmium and lead complexes. We have also performed multinuclear (109)Ag, (113)Cd, (119)Sn and (207)Pb studies for silver, cadmium, tin and lead compounds, respectively. Moreover we present here a comparative study on the different structures found for pentadentate thiosemicarbazonate complexes, trying to check the influence of different factors, such as experimental procedure, size of metal, structure of the ligand, and metal oxidation state, on the final structure of the complex formed. Our aim is gaining a better insight into the coordination trends of pentadentate thiosemicarbazone ligands.

The coordination behaviour of a new thiosemicarbazone Schiff-base building block, N-{2-([4-N-ethylthiosemicarbazone]methyl)phenyl}-p-toluenesulfonamide, H2L1 (1), incorporating a bulky tosyl group, towards Mn II, Fe II, Co II, Ni II, Cu II, Zn II, Cd II, Ag I, Sn II, and Pb II has been investigated by means of an electrochemical preparative procedure. Most metal complexes of L1 have the general formula [M(L1)]2.nX (M=Mn, Fe, Co, Ni, Cu, Cd, Pb; n=0-4, X=H2O or CH3CN), as confirmed by the structure of [Pb(L1)]2 (15), in which the lone pair on lead is stereochemically active. This lead(II) complex shows an intense fluorescence emission with a quantum yield of 0.13. In the case of silver, the complex formed was found to possess a stoichiometry of [Ag2(L1)]2.3H2O. During reactions with manganese and copper metals, interesting catalysed processes have been found to take place, with remarkable consequences regarding the ligand skeleton structure. In synthesising the manganese complex, we obtained an unexpected dithiolate thiosemicarbazone tosyl ligand, H2L2, as a side-product, which has been fully characterised, including by X-ray diffraction analysis. In the case of copper, the solid complex has the formula [CuL1]2, but the crystallised product shows the copper atoms coordinated to a new cyclised thiosemicarbazone ligand, H2L3, as in the structures of the complexes [Cu(L3)]2.CH3CN (8) and [Cu(L3)(H2O)]2.CH3CN.H2O (9). The zinc complex [Zn(L1)]4 (12) displays a particular tetranuclear zeolite-type structure capable of hosting small molecules or ions, presumably through hydrogen bonding.

Negative emotional pictures from the International Affective Pictures System (IAPS) have been successful in mapping brain areas related to the aversive system. However, the capacity of positive emotional pictures to study the brain areas related to the appetitive system (i.e., nucleus accumbens, prefrontal cortex) is less established. In this study, we used a block fMRI design to investigate this issue, including emotional pictures as background while participants performed a vowel-consonant discrimination task. Importantly, participants were heterosexual males and all positive pictures were related to erotic couples, opposite-sex erotica, or romantic scenes. Negative pictures were similar to those used in previous studies. Results were consistent with previous studies using event-related designs, showing activation of amygdala, lateral prefrontal cortex, and occipito-temporal areas, but positive pictures showed a significant activation in the left nucleus accumbens. These findings provide evidence of the utility of block designs in emotional research (positive emotional pictures).

A fluorinated salt-free catanionic system leads to the formation of spherical vesicles that transform over time into polyhedral vesicles. This is the first example of isolated faceted vesicles with fluid bilayers.

A unique case of a grid-of-mesocates sequentially assembled by supramolecular cobalt(II) meso-helical units connected through hydrogen bonding is reported.

Water reduction can be electrochemically promoted by zinc under very mild conditions, as demonstrated by the formation of the complex [Zn(H(2)O)(6)][Zn(3)(L)(3)(mu(3)-O)], whose anion consists of a Zn(3)O(4) cluster incorporating a mu(3)-oxo anion.

The coordinative chemistry of the tridentate thiosemicarbazone ligand 2-pyridinecarboxaldehyde 4-N-ethylthiosemicarbazone (HL(Et)) has been explored by using an electrochemical methodology. All the complexes have been characterized using analytical and spectroscopic techniques. In the case of copper we have isolated two different complexes, with Cu(L(Et))(2).4H(2)O (6) and [Cu(2)(L(Et))(2)(SO(4))] (7) formulae. The sulfate group coordinated to the copper atoms in was probably released to the media as a consequence of a desulfurization process. Single X-ray crystallography has been carried out for the ligand HL(Et) and the complexes , [Ag(6)(L(Et))(6)].CH(3)CN (9) and [Pb(L(Et))(2)] (2). The copper(ii) complex is a dimer compound in which two antiparallel monodeprotonated ligands are coordinated to two copper centres by establishment of mu(2)-thiolate bridges and the additional coordination of a sulfate group bridging the two metal atoms. The silver complex is an unusual hexanuclear cluster compound with a wheel-type conformation, while the lead complex is a monomer which exhibits the lone pair effect. A structural comparative study of the electrochemically obtained complexes derived from HL(X) ligands (X= Me, Et and Ph) have been performed. Finally, the solution behaviour of the complexes was checked by NMR, UV and fluorescence studies.