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The present study aimed to determine whether the inclusion of a mixture based on Saccharomyces cerevisiae lysate, zeolite, silicon dioxide, propylene glycol, Carduus marianus extract, soy lecithin, and carbonate in the piglet diet would be able to minimize the negative effects caused by feed with aflatoxin; a study focusing on animal health and performance. Seventy-two entire male piglets (7.35 ± 1.17 kg) weaned with an average of 26 days were used, allotted into four groups, with six repetitions (pens) per group and three piglets/pen. The treatments were as follows: NoAfla-NoAntiMyc - negative control (without aflatoxin); Afla-NoAntiMyc - positive control (500 ppb of aflatoxin); NoAfla-AntiMyc - 1000 mg/kg of anti-mycotoxin mixture; Afla-AntiMyc - 500 ppb aflatoxin + 1000 mg/kg anti-mycotoxin. We evaluated the performance (feed intake - FI, weight gain - WG and feed:gain ratio- FGR) andblood variables (10 days between samples). On day 32, six pigs from each group (a total of 24 pigs) were slaughtered to collect fragments of the liver, intestine, and spleen for analysis of oxidants/antioxidants and histology. It was observed that piglets in the positive control group (Afla-NoAntiMyc) had lower body weight and weight gain when compared to the other groups during the experimental period. Also, piglets from Afla-NoAntiMyc consumed less feed between days 1 to 20 and 1 to 30 compared to NoAfla-NoAntiMyc. A considerable increase in liver enzymes aspartate aminotransferase and alanine aminotransferase in the piglets' serum of Afla-NoAntiMyc compared to other treatments, which indicates that the anti-aflatoxin blend worked. Fewer neutrophils and an increase in monocyte were observed in the piglets of Afla-NoAntiMyc compared to NoAfla-NoAntiMyc; changes that were not seen in the animals of Afla-AntiMyc. We did not see any change in the oxidant and antioxidant status in the piglet serum during the experimental period; different from what happened in Afla-NoAntiMyc piglets in the liver (higher glutathione reductase activity and levels of reactive oxygen species - ROS), in the spleen (higher levels of ROS) and the intestine/jejunum (reduction of nitrate/nitrite levels - NOx). Intestinal morphometry revealed that piglets from Afla-NoAntiMyc had higher villus height than the other groups, while the folded size was smaller in this group. The crypt depth was greater in the intestine of piglets in both treatments that consumed aflatoxin. In general, it is concluded that the consumption of aflatoxin B1 by piglets has negative impacts on the health and, consequently, the animals' performance; however, supplementation of the contaminated feed with an anti-mycotoxin blend was able to protect the piglets, minimizing the negative problems caused by the mycotoxin.

Metal complexes still represent promising pharmacological tools in the development of new anticancer drugs. Bis(citronellalthiosemicarbazonate)nickel(ii) is a metal compound extremely effective against leukemic and NCS cancer cell lines. Preliminary experiments performed with this compound and with its Cu(ii) and Pt(ii) analogues evidenced alterations, detectable by comet assay, in the DNA of treated U937 cells. In addition, [Cu(tcitr)2] and [Pt(tcitr)2] were also able to induce gene mutations and produce frameshift events. To gain further insights into the mechanism of action of these metal compounds, we carried out a multidisciplinary study to investigate whether their biological activity can be ascribed to the direct interaction with DNA or with chromatin. The DNA interaction was investigated by means of CD and UV-Vis spectroscopic techniques and by AFM, whereas the chromatin interaction was studied by analyzing the effects of the compounds on the structure of a peptide that mimicks the potential metal binding site in the “C-tail” region of histone H2A by means of NMR, CD, UV-Vis and MS. The intensities of the effects induced by the metal compounds on the peptide follow the order [Ni(tcitr)2] > [Pt(tcitr)2] ≫ [Cu(tcitr)2]. From the AFM data, a remarkable DNA compaction was observed in the presence of [Pt(tcitr)2], while [Ni(tcitr)2] causes the formation of large interlaced DNA aggregates.

Fluorescent properties of indocyanine green (ICG) for hepatic tumor identification and features have been recently studied. The aim is to review the published data on the use of ICG enhanced fluorescence surgery during liver resection. A systematic search of literature was performed using MEDLINE, EMBASE, Cochrane and Web of Science libraries. For all eligible studies, the following data were extracted: study design, number of cases, management of indocyanine green (dose, time and method of administration), type of surgery, outcome variables, false positive and accuracy value, if reported. For statistical analysis, it was considered significant P

A comparative study between two bisthiosemicarbazones, 2,3-butanedione bis(4,4-dimethyl-3-thiosemicarbazone) and 2,3-butanedione bis(2-methyl-3-thiosemicarbazone), and their copper(ii) complexes is reported. The four compounds have been tested on a leukemia cell line U937 (p53-null) and on an adenocarcinoma cell line A549. The study includes cell viability, cell cycle, morphological changes, assessment of apoptosis, analysis of autophagy, measurement of reactive oxygen species (ROS) and of lipid peroxidation, protein determination, assessment of the expression of p53 and cellular uptake of metal complexes. Tests about the copper uptake under normoxic and hypoxic conditions were also carried out on a solid tumour cell line A549. The four compounds under study elicit different effects on the two lines adopted as representatives of p53 and p53-null cells. The role of the metal is relevant and it is likely that the metal-mediated oxidative stress plays an essential role in the whole process. The mechanisms induced by these molecules differ not only as a function of the cell line but also of dose. The responses include two distinct self-destructive processes, autophagy and apoptosis.

In this paper, we report the syntheses, characterization and studies on the inhibition efficiency in mild steel acidic corrosion of 4-fluorobenzaldehyde thiosemicarbazone, Hfbt, 4-fluorobenzaldehyde 2-methylthiosemicarbazone, Me-fbt, and their Zn(II) complexes [Zn(fbt)2] and [Zn(Me-fbt)2]Cl2. The ligands present a good degree of activity that can be assigned to their molecular planar shape and to the presence of electron lone pairs that can interact with metal orbitals. The two zinc complexes present diametrically opposite properties: [Zn(fbt)2] is by far less active than the ligands, while [Zn(Me-fbt)2]Cl2 is the most efficient. Quantum chemical studies were carried out in an attempt to rationalize this behaviour.

In this paper, citronellal, vanillin and pyridoxal thiosemicarbazones were modified with polar substituents, namely ethylmorpholine and glucose, to increase their polarity and compare the effects of these moieties on their biological activity. Altogether, nine ligands were synthesized and for each of them also their copper(II) and nickel(II) complexes were prepared and used for the biological tests. Eventually, assays on proliferation inhibition were conducted using leukemic cell line U937, already used as a model for previous citronellal thiosemicarbazone tests. Biological tests were also performed on solid tumor cell line HT29. From the first screenings, two of the metal complexes showed remarkable interesting properties, and, therefore, were also tested for histosensitivity.

The aim of this work is to evaluate the effects of molecular weight, hydrolysis degree, and cross-link on the performance of Polyvinyl Alcohol (PVA) when applied as dielectric material in organic field effect transistors. For this purpose, metal–insulator-structures and polymeric films were characterized. The polymer structure was analyzed by thermogravimetry and calorimetry, and the electrical characterization of the films was performed through current–voltage and capacitance–voltage curves; and dielectric spectrometry. Cross-linkage, followed by hydrolysis degree, presented the major impact on polymer properties, due to the strong influence on chain mobility. The chain mobility increases the dielectric response and decreases the insulation capacity, generating the need to compromise between these two properties. The largest drawback encountered was the high sensitivity of the films to ambient humidity. The best performance of the organic insulator was obtained from cross-linked films made of an incompletely hydrolyzed PVA.

The syntheses of four compounds, obtained by the reaction of methylpyruvate thiosemicarbazone (Hmpt) and its methyl (Me-Hmpt) and allyl (Allyl-Hmpt) derivatives with bis(triphenylphosphine)copper(I) acetate, are reported. The compounds [Cu(PPh3)2(ptc)(Hptc)]·H2O (1), [Cu(PPh3)2(Me-ptc)] (2), [Cu2(PPh3)2μ-S(Me-pt)μ-S(Me-ptc)]·H2O (3) and [Cu(PPh3)2(Allyl-ptc)] (4) [H2pt = pyruvic acid thiosemicarbazone and Hptc = cyclized pyruvic acid thiosemicarbazone, Me = methyl and Allyl are radical substituents on the amino nitrogen] were characterized by elemental analysis, IR, 1H NMR, and by X-ray crystallography. Compound 3 was also studied by EPR because of the presence in the compound of two copper atoms in two different oxidation states. During the complexation reaction, the thiosemicarbazone ligands tend to undergo a cyclization reaction that leads to the formation of a six-member heterocyclic ring. All four compounds present the [Cu(PPh3)2]+ fragment and constant but different coordination situations. Compound 1 contains two cyclic ligand molecules, one protonated and the other deprotonated, bound as monodentate through the sulfur. Compounds 2 and 4 present a single deprotonated cyclic SN bidentate ligand molecule, while compound 3 contains copper(I) and copper(II), and two ligand molecules, one of which is linear and behaves as SNO tridentate and the other is cyclic and behaves as bridging μSN.

Thiosemicarbazones are versatile organic compounds that present considerable pharmaceutical interest because of a wide range of properties. In our laboratory we synthesised some new metal-complexes with thiosemicarbazones derived from natural aldehydes which showed peculiar biological activities. In particular, a nickel complex [Ni(S-tcitr)(2)] (S-tcitr=S-citronellalthiosemicarbazonate) was observed to induce an antiproliferative effect on U937, a human histiocytic lymphoma cell line, at low concentrations (IC(50)=14.4microM). Therefore, we decided to study the interactions of this molecule with various cellular components and to characterise the induced apoptotic pathway. Results showed that [Ni(S-tcitr)(2)] causes programmed cell death via down-regulation of Bcl-2, alteration of mitochondrial membrane potential and caspase-3 activity, regardless of p53 function. The metal complex is not active on G(0) cells (i.e. fresh leukocytes) but is able to induce perturbation of the cell cycle on stimulated lymphocytes and U937 cells, in which a G(2)/M block was detected. It reaches the nucleus where it induces, at low concentrations (2.5-5.0microM), DNA damage, which could be partially ascribed to oxidative stress. [Ni(S-tcitr)(2)] is moreover able to strongly reduce the telomerase activity. Although the biological target of this metal complex is still unknown, the reported data suggest that [Ni(S-tcitr)(2)] could be a good model for the synthesis of new metal thiosemicarbazones with specific biological activity.

This paper reports the synthesis of a series of methylpyruvate thiosemicarbazone derivatives containing, on the terminal nitrogen, substituents of different nature and size and namely, ethyl, phenyl and methylphenyl. These ligands were reacted with bis(triphenylphosphine)copper(I) nitrate and acetate to produce the respective complexes: [Cu(PPh3)2(Et-Hmpt)]2(NO3)2 (1), [Cu(PPh3)2(Ph-Hmpt)]NO3 (2), [Cu(PPh3)2(MePh-Hmpt)]NO3 (3), [Cu2(O2CCH3)(Et-pt)(PPh3)2] · H2O (4), [Cu(Ph-mpt)(PPh3)] (5) and [Cu2(MePh-mpt)2(PPh3)2] (6). All of them were characterized by elemental analysis, IR, 1H NMR, EPR spectroscopy and, for compounds 1, 2, 4, and 6, by X-ray crystallography. The characterization revealed that the coordinating behaviour of the ligands is influenced by a series of factors, predominant among which is the hard soft nature of the atoms involved in the interactions with the metal centre. The complexes obtained from the nitrate copper(I) salt are formed by cationic molecules with a nitrate as a counterion, while those derived from the acetate salt present deprotonated ligands and a few unexpected features. In particular, one of the compounds (4) is a mixed valence dinuclear complex with an acetate oxygen and the thiosemicarbazone sulfur acting as bridging between the two Cu(I) and Cu(II) ions. Another one (6) presents instead a Cu(I)–Cu(I) sulfur bridged binuclear cluster.

By reacting thiosemicarbazides substituted on the aminic nitrogen with 5-formyluracil, several new 5-formyluracil thiosemicarbazones (H 3 ut) derivatives were synthesised and characterized. These ligands, treated with copper chloride and nitrate, afforded two different kinds of compounds. In the complexes derived from copper chloride the metal atom is pentacoordinated, being surrounded by the neutral ligand binding through SNO donor atoms and by two chlorines, while the nitrate derivatives consist of monocations and nitrate anions. The copper coordination (4 + 2) involves the SNO ligand atoms, two water oxygens and an oxygen atom of a monodentate nitrate group. On varying the substituents on the thiosemicarbazidic moiety, remarkable modifications of the coordination geometry are not observed for the complexes with the same counterion. For all the compounds, interactions with DNA (calf thymus) were studied using UV–Vis spectroscopy; the nuclease activity was verified on plasmid DNA pBR 322 by electrophoresis.

In the course of a research on metal-based compounds active on white blood cell cancers (leukemia, lymphoma and myeloma) nine aliphatic thiosemicarbazones and their nickel complexes have been synthesized with the aim to test their effect on histiocytic lymphoma U937 cell proliferation. All compounds were characterized by elemental, IR and NMR spectra analyses and for five of the complexes also by X-ray crystallography diffraction analysis. Heptanal thiosemicarbazone and the corresponding nickel complex were chosen after a solubility/stability test to carry out preliminary experiments in vitro on human leukemia cell line U937. The complex possesses a remarkable biological activity in inhibiting cell growth and in inducing apoptosis.

This paper reports the synthesis and characterization of six compounds of copper(I), stabilized in its reduced state by two triphenylphosphines, in which 4-fluorobenzaldehyde thiosemicarbazone and N-methylthiosemicarbazone act as chelating through their sulfur and imino nitrogen. The three oxoanions that have been chosen, NO3−, SO42− and CH3COO−, play an important role: their oxygens are bad competitors with the imino nitrogen of the thiosemicarbazone moiety and moreover they form strong charge assisted hydrogen bondings that stabilize the neutral form of the ligand. The overall packing is determined by intermolecular phenyl–phenyl van der Waals interactions.

Reaction of phenylisothiocyanate with different aromatic amines allowed the synthesis of compounds containing the thiourea moiety. By reacting silver bis(triphenylphosphine)nitrate with suitable ligands belonging to this family of sulphurated compounds, three new complexes have been afforded. Ligands and complexes were characterized also by X-ray diffraction. The structures reveal remarkable differences in the silver coordination geometry in function of the nature and size of the ligand. The emission properties of all compounds were characterized at 10 and at 298 K.

9-cis-Retinal thiosemicarbazone and its Co(III), Ni(II) and Cu(II) complexes are synthesized and characterized. Central Co(III) atom is in an octahedral environment while Ni(II) and Cu(II) atoms are in a square planar environment. DNA binding constants and spectroscopic data show an intercalative behavior for the nickel complex; an external binding mode is envisaged for the ligand and its copper complex. No DNA interaction can be hypothesized for the cobalt complex. The free ligand and its Ni(II) and Cu(II) complexes have a good lipophilic degree for an efficient uptake by the cells. The metal complexes exhibit a proliferation inhibition action against cell line U937 at micromolar concentration. Cu(II) complex also induces apoptosis, while Ni(II) complex has a strong interaction with CT-DNA.

A series of quinoline-2-carboxaldehyde thiosemicarbazones and their copper(II) and nickel(II) complexes were synthesized and characterized. In all complexes the ligands are in the E configuration with respect to the imino bond and behave as terdentate. The copper(II) complexes form square planar derivatives with one molecule of terdentate ligand and chloride ion. A further non-coordinated chloride ion compensates the overall charge. Nickel(II) ions form instead octahedral complexes with two ligands for each metal ion, independently from the stoichiometric metal:ligand ratio used in the synthesis. Ligands and complexes were tested for their antiproliferative properties on histiocytic lymphoma cell line U937. Copper(II) derivatives are systematically more active than the ligands and the nickel complexes. All copper derivatives result in inhibiting topoisomerase IIa in vitro. Computational methods were used to propose a model to explain the different extent of inhibition presented by these compounds. The positive charge of the dissociated form of the copper complexes may play a key role in their action.

Two new 5-formyluracil thiosemicarbazone (H(3)ut) derivatives, Me-H(3)ut (1) and Me(2)-H(3)ut (2), were synthesized by reacting thiosemicarbazides, mono- and dimethylated on the aminic nitrogen, with 5-formyluracil and were subsequently characterized. These ligands, treated with copper chloride and nitrate, afforded three complexes: [Cu(Me-H(3)ut)Cl(2)].H(2)O (3), [Cu(Me(2)-H(3)ut)Cl(2)].H(2)O (4), and [Cu(Me-H(3)ut)(NO(3))(OH(2))(2)]NO(3) (5). The crystal structures of these complexes have been determined by single-crystal X-ray diffraction. In 3 and 4, a similar pentacoordination is present; the copper atom is surrounded by the ligand SNO donor atoms and by two chloride ions. The structure of 5 consists of [Cu(Me-H(3)ut)(NO(3))(OH(2))(2)](+) cations and nitrate anions. The copper coordination (4 + 2) involves the SNO ligand atoms and a water oxygen in the basal plane; the apical positions are occupied by a second water oxygen and by an oxygen of a monodentate nitrate group. Two biochemical techniques, namely DNA titration in the UV-vis region and thermal denaturation, have been employed to probe the details of DNA binding of these compounds. Analysis of the results suggests that our compounds are able to interact with DNA by electrostatic and groove binding but not by intercalation. The compounds have been also tested in vitro on human leukemic cell line U937, but they are not able to inhibit significantly cell proliferation.

Background The availability of new agents (NAs) active in patients with metastatic castration-resistant prostate cancer (mCRPC) progressing after docetaxel treatment (abiraterone acetate, cabazitaxel, and enzalutamide) has led to the possibility of using them sequentially to obtain a cumulative survival benefit. Objective To provide clinical outcome data relating to a large cohort of mCRPC patients who received a third-line NA after the failure of docetaxel and another NA. Design, setting, and participants We retrospectively reviewed the clinical records of patients who had received at least two successive NAs after the failure of docetaxel. Outcome measurements and statistical analysis The independent prognostic value of a series of pretreatment covariates on the primary outcome measure of overall survival was assessed using Cox regression analysis. Results and limitations We assessed 260 patients who received one third-line NA between January 2012 and December 2013, including 38 who received a further NA as fourth-line therapy. The median progression-free and overall survival from the start of third-line therapy was, respectively, 4 mo and 11 mo, with no significant differences between the NAs. Performance status, and haemoglobin and alkaline phosphatase levels were the only independent prognostic factors. The limitations of the study are mainly due its retrospective nature and the small number of patients treated with some of the sequences. Conclusions We were unable to demonstrate a difference in the clinical outcomes of third-line NAs regardless of previous NA therapy. Patient summary It is debated which sequence of treatments to adopt after docetaxel. Our data do not support the superiority of any of the three new agents in third-line treatment, regardless of the previously administered new agent.

Synthesis and characterization of new thiosemicarbazones derived from natural aldehydes ( 1 – 9 ) have been investigated in order to develop a research program aimed at the development of compounds with antiviral, antibacterial, and antitumor properties. These substances contain both a chain with N and S nucleophilic centers with tuberculostatic activity, and an alkyl or terpenic moiety. In addition, a few nickel(II) and copper(II) complexes ( 10 – 18 ), derived also from the previously studied ligands, were synthesized and characterized by means of NMR and IR techniques. The trans -2-octenal N 1 -phenylthiosemicarbazone and its nickel complex were also characterized by X-ray diffractometry. Biological studies, performed with some of these compounds, have involved both inhibition of cell proliferation and apoptosis tests in vitro on human leukemia cell line U937 to deepen our knowledge on the way these substances interfere with biological processes in leukemic cells.

In this paper we describe the synthesis of new copper complexes with alpha-ketoglutaric acid thiosemicarbazone. The crystal structures of the two compounds: [Cu(H(2)ct)Cl](n) [(Cu(H(2)ct)Cl)(2)] (1) and [Cu(Hct)](n).3nH(2)O (2) (H(3)ct=alpha-ketoglutaric acid thiosemicarbazone) have been determined by X-ray and spectroscopic methods. In 1 two independent copper atoms are present. Cu(1), in a nitrogen- and oxygen-bridged polymer, is a six-coordinated (4+2), Cu(2), five coordinated (4+1), is a chlorine-bridged dimer. In 2 the copper atom presents a penta-coordination, polymeric chains form layers and the -CH(2)CH(2)COO(-) groups bridge copper atoms. In 1 a monodentate and in 2 a syn-anti bidentate bridging carboxylate are present. The biological properties of 1 and 2 and also of the free ligand (H(3)ct) were tested in vitro and compared on Friend erythroleukemia cells (FLC) and on human leukemia cell lines K562 and U937. On the FLC cells the free ligand does not inhibit cell growth, but increases the DNA synthesis; complex 1 inhibits cell proliferation and increases the DNA synthesis; complex 2 inhibits cell growth, but induces a decrement of DNA synthesis and increases the reverse transcriptase activity. Regarding the human cell lines, both complexes show proliferation inhibition through an apoptosis mechanism on cell line U937, while they have no effects on the K562 line.

Novel ligands were obtained by condensation of pyridoxal with thiosemicarbazides substituted with alkyl and aryl moieties on the aminic and/or hydrazinic nitrogen. The spectrophotometric characteristics of the various species are reported. The X-ray structure of two different dimethylthiosemicarbazones of pyridoxal — pyridoxal N1,N2-dimethylthiosemicarbazone monohydrate and pyridoxal N1,N1-dimethylthiosemicarbazone monohydrate — was determined. The change of methyl group position determines in the solid state strong differences which affect the ligand behavior of these compounds. In the first ligand, characterized by X-ray diffraction, the pyridoxal ring is in a zwitterion form, with the phenolic oxygen and the sulfur atoms in trans position to the iminic N atom. The second compound, with both methyl groups on the aminic nitrogen, shows the donor atoms SNO on the same side, making it potentially suitable for coordination to the metal. Biological studies have involved both inhibition of cell proliferation ...

By reacting thiosemicarbazides substituted on the aminic nitrogen with both alkyl or aryl groups, and methyl pyruvate a new group of methylpyruvate thiosemicarbazones (Hmpt) derivatives was obtained. These ligands were then treated with copper and zinc inorganic salts. All isolated compounds were characterized using spectroscopic methods. The single crystal structural analysis of the ligands Me–Hmpt·0.5H 2 O 1 , Et–Hmpt·H 2 O 2 , Ph–Hmpt 5 , Meph–Hmpt 6 showed that only compound 6 presents significant deviation from planarity. The X-ray structure of [Zn(Me–Hmpt)Cl 2 ]·H 2 O 8 showed that in this complex Me–Hmpt behaves as a neutral ligand SNO terdentate and that the penta coordination is achieved by chloride ions according to spectroscopic and elemental analyses. On the basis of the analytical data the same behavior is proposed for the other zinc complexes. All the ligands in copper complexes seem to be monodeprotonated; nevertheless the same SNO behavior is expected. Tests on cell proliferation of human leukemic cell line U937 showed that the copper complex Cu(Et–mpt)Cl·H 2 O is the most active compound among those reported even though it is not able to induce apoptosis.

New thiosemicarbazone nickel complexes (1–7), derived from p-fluorobenzaldehyde and differently substituted thiosemicarbazides, were synthetized and characterized by means of NMR and IR techniques. The p-fluorobenzaldehyde 4-ethylthiosemicarbazone Et-Hfbt (1) and its complex [Ni(Et-fbt)2] (2) were also characterized by X-ray diffractometry. Molecule 1 consists of two units: the p-fluorobenzaldehyde residue and the thiosemicarbazonic chain. In the reaction of 1 with NiAc2·4H2O, complex 2 was afforded. The molecular structure of 2 consists of the neutral complexes [Ni(Et-fbt)2] with the metal not lying on a symmetry centre, with two consequently independent ligand molecules; the coordination results in a square planar geometry slightly twisted towards a tetrahedron, involving the sulfur and the hydrazine nitrogen atoms of the two ligands in a trans configuration.

Three new complexes of transition metals as copper, nickel and cobalt with 5-formyluracil thiosemicarbazone (H3ut) have been synthesised and characterised by single-crystal X-ray diffraction. In all compounds the ligand behaves as SNO terdentate. In the copper complex the coordination geometry is square pyramidal with the ligand lying on the basal plane and two water molecules that complete the metal environment, the nickel compound is surrounded by six donor atoms (three of the ligand, two water oxygen atoms and a chlorine atom) in an octahedral fashion, and cobalt also shows an octahedral geometry but determined only by two terdentate ligand molecules. These three compounds have been tested on human leukemic cell lines K562 and CEM. The nickel and cobalt complexes have demonstrated low activity in cell growth, while the copper complex that is more active has been tested also on a third leukemic human cell line (U937), but it was not able to induce apoptosis on all cell lines.

In this paper we report the synthesis of three new complexes of Zn(II) and Co(III) with two ligands, methyl pyruvate thiosemicarbazone (Hmpt) and α-ketoglutaric acid thiosemicarbazone (H3ct). The three compounds [Zn(H2pt)(Hpt)Cl] (A), [Zn(H2ct)2]·H2O (B), [Co(H2ct)(Hct)]·H2O (C), are characterized by IR spectroscopic techniques and the structures determined by single-crystal X-ray diffraction analysis. In A an interesting feature is the different behavior of the two ligand molecules, one terdentate and the other monodentate. The coordination geometry about zinc is better described as intermediate between an ideal square pyramid and trigonal bipyramid, while in B and C the metals are six-coordinated in a distorted octahedral geometry. All compounds are monomeric.

As part of a research programme aimed at the synthesis of compounds with antiviral, antibacterial and antitumor properties and their spectroscopic characterization, new thiosemicarbazones deriving from natural aldehydes have been investigated. These substances contain in the same molecule both a chain with nucleophilic centres N, S with tubercolostatic activity, and a glycosidic or alkyl moiety (modified glycosides and nucleosides have recently received a great deal of attention in the fields of neoplastic diseases and viral infections). In this paper the synthesis and the characterization of these compounds by means of 1H NMR, IR, and MS techniques is reported. Biological studies have involved both inhibition of cell proliferation and apoptosis tests on human leukemia cell line U937.

Chiral porphyrins 1 and 2, bearing, respectively, four and two chains at the meso carbons, each one with a stereocentre at C-2 and a double bond at C-5, were functionalized to afford the corresponding thiosemicarbazonic derivatives 9–12 and the nickel(II) porphyrinato 13, compounds with potential antiviral, antibacterial and antitumour properties. To verify the biological activity of some of these products, assays of proliferation inhibition and apoptosis tests in vitro on human leukemic cell lines U937 were carried out for compounds 1, 6, 9 and 10.

A dimeric copper complex of the unsubstituted pyridoxal thiosemicarbazone (H(2)L), [[Cu(HL)(OH(2))](2)]Cl(2).2H(2)O, previously tested on Friend murine cell lines has been recently resynthesized to evaluate its behavior on different murine and human leukemic cell lines and has been compared, in vitro and in vivo, with its monomeric counterpart [Cu(H(2)L)(OH(2))Cl]Cl. On TS/A murine adenocarcinoma cell line in vitro, both compounds significantly inhibit cell proliferation at micromolar concentrations, although the dimeric compound is more active. Despite this cytotoxicity they lack in vivo activity on TLX5 lymphoma. The unsubstituted dimeric [[Cu(HL)(OH(2))](2)]Cl(2).2H(2)O induces apoptosis on CEM and U937 human cell lines, with IC(50) concentrations of 1.2 x 10(-5) and 6.7 x 10(-6) M, respectively, but it is inactive on K562. Moreover, it alters significantly the cell cycle of U937 and CEM lines and decreases the telomerase activity of U937. To verify if other dimeric copper complexes show relevant biological activity new complexes with N-substituted pyridoxal thiosemicarbazones have been synthesized and characterized using spectroscopic techniques. Three of them, namely [Cu(Me(2)-HL)Cl](2).6H(2)O (Me(2)-H(2)L=pyridoxal N1,N1-dimethylthiosemicarbazone) (1), [Cu(MeMe-HL)Cl](2)Cl(2).4H(2)O (MeMe-HL=pyridoxal N1,N2-dimethylthiosemicarbazone) (2), [Cu(Et-H(2)L)Cl](2)Cl(2).2H(2)O (Et-H(2)L=pyridoxal N1-ethylthiosemicarbazone) (3), were also characterized by X-ray diffractometry. These complexes are dimeric and all three present a square pyramidal coordinative geometry with the ligand showing an SNO tridentate behavior. Their biological activities have been tested in vitro on U937, CEM and K562 cell lines to ascertain their effectiveness in comparison to the corresponding unsubstituted complex [[Cu(HL)(OH(2))](2)]Cl(2).2H(2)O. Compound 1 shows weak proliferation inhibition on all three cell lines, but it does not induce apoptosis and it does not inhibit telomerase activity, compound 2 is not effective at low concentration and is toxic at higher doses; compound 3 inhibits CEM cell growth better than complex 1 but it does not exert any other biological effect.

While most of the research on the area of organic field effect transistors (OFET) concentrates on the development and characterization of the semiconductor, the dielectric layer plays an important role on the performance of the device. PVA is an attractive candidate to this role due to its favorable properties. The structure of the polymer can be engineered through different parameters, which can be used to optimize the characteristics of the film depending of the desired properties. In this work we report an evaluation of the effect of different molecular weight, hydrolysis degree, and reticulation on the performance of the PVA to be applied as a gate dielectric in OFET. The methodology created simplifies the characterization of the dielectric material, excluding the influence of the semiconductor. The analysis of polymer structure was made by DSC analysis and the analysis of the film properties was based on the study of MIS capacitors. Crosslinkage presents the major impact on the polymer properties, followed by degree of hydrolysis, due to their large influence on chain mobility. An increase on chain mobility affects positively dielectric response and negatively insulation capacity, generating the need of compromise between these two properties. The largest drawback encountered was the high sensitivity of the films to environmental conditions, especially moisture, which contributed negatively to increase on hysteresis.

Manganese(II), nickel(II), and copper(II) complexes of 2,6-diacetylpyridine bis (acetylhydrazone) (H2dapac) have been synthesized and structurally characterized by X-ray diffraction methods. [Mn(H2dapac) (OH2)2](NO3)2 crystallizes in the monoclinic space groupP21/c witha=11.145(3),b=10.723(4),c=17.189(2) A, β=92.81(2)° andZ=4; [Ni(H2dapac)(OH2)2] (NO3)2·H2O crystallizes in the monoclinic space groupP21 witha=9.994(3),b=14.423(4),c=7.697(2)A, β=100.37(2)°, andZ=2; [Cu(H2dapac)(OH2)2](NO3)2·H2O crystallizes in the orthorhombic space groupPbcn witha=20.986(5),b=14.552(3),c=6.905(1)A andZ=4. In each case the metal atom has a slightly distorted pentagonal bipyramidal environment, the equatorial positions being occupied by three nitrogen and two oxygen atoms from the hydrazone ligand and the apices by two water molecules. The crystalline cohesion in ensured by a three-dimensional network of hydrogen bonds involving the complex cations, the nitrate anions, and, where present, the uncoordinate water molecules.

The reaction of zinc chloride, acetate, or perchlorate with two bis(thiosemicarbazones) of 2,6-diacetylpyridine [H2daptsc = 2,6-diacetylpyridine bis(thiosemicarbazone) and H2dapipt = 2,6-diacetylpyridine bis(hydrazinopyruvoylthiosemicarbazone)] leads to the formation of four novel complexes that have been characterized by spectroscopic studies (NMR, IR) and biological properties. The crystal structures of the two compounds--[Zn(daptsc)]2.2DMF (1) and [Zn(H2dapipt)(OH2)2](CIO4)2.3H2O (2)--also have been determined by x-ray methods from diffractometer data. Compound (1) is dimeric and the two zinc atoms have a distorted octahedral coordination. The ligand is deprotonated. In compound (2), the coordination geometry about zinc is pentagonal--bipyramidal and the ligand is in the neutral form. The molecular structure of (2) consists of cations [Zn(H2dapipt)(OH2)]2+, CIO4- disordered anions, and three water molecules of solvation. Biological studies have shown that the ligands and the complexes Zn(daptsc).1/2EtOH and Zn(H2daptsc)Cl2 have an effect in vitro on cell proliferation and differentiation (inhibition); both are concentration dependent. [Zn(daptsc)]2.2DMF (1) shows the effects at lower concentration values with respect to other compounds.

Two new cobalt(III) complexes with pyridoxal [3-hydroxy-5-(hydroxymethyl)-2-methylpyridine-4-carbaldehyde] and pyruvic acid thiosemicarbazones (H2L and H2pt)[Co(HL)2]Cl·EtOH 1 and [Co(Hpt)(pt)]2 respectively, have been synthesized and characterized using single-crystal X-ray diffraction and IR and CD spectroscopic methods. The structure of 2-thio-6-azathymine [6-methyl-3-thioxo-1,2,4-triazin-5-(2H,4H)-one] obtained upon cyclization of methyl pyruvate thiosemicarbazone in the course of its complexation reaction with cobalt(II) salts is also described. The structure of 1 consists of discrete [Co(HL)2]+ cations, Cl– anions and ethanol solvate molecules, that of 2 consists of neutral monomers and the two ligands are not equivalent. In both complexes the co-ordination geometry about cobalt is distorted octahedral and the two ligands are in the mer configuration (S and O atoms cis to each other and the N atoms trans). Complex 1, an example of optical resolution by preferential crystallization, is chiral.

To improve the solubility in aqueous media of bis(citronellalthiosemicarbazonato)copper(II) [Cu(S-tcitr) 2 ], a compound that is effective in inhibiting cell growth of U937 cell line, the ligand was modified adding an ethylmorpholine group. [Cu(S-tcitr) 2 ] and [Cu(Etmorph-S-tcitr) 2 ] cytotoxic effects are compared using as a model U937 cells. [Cu(Etmorph-S-tcitr) 2 ] results more effective in cell growth inhibition (IC 50: 2.3 vs 14.8 μM). Apoptosis in [Cu(Etmorph-S-tcitr) 2 ] treated cells was apparent after 8 h, with increased caspase activities, and these effects were not observed for [Cu(S-tcitr) 2 ]. During the exposure to [Cu(Etmorph-S-tcitr) 2 ], ROS (reactive oxygen species) and TBARS (Thiobarbituric acid reactive substances) significantly increased, coupled with reduced glutathione (GSH) levels and significant activation of superoxide dismutase (SOD). These intracellular scavengers seem to limit the early ROS and TBARS increases in U937 cells exposed to [Cu(S-tcitr) 2 ]. Both complexes interacted in vitro with naked DNA: UV–visible and CD titration reveal that they can induce DNA structure modifications in a distinct way. Furthermore, the complexes induced DNA damage on U937 cells at concentrations higher than IC 50 . The mechanisms of action and the effects of these two complexes are remarkably different even though they have the same coordination geometry around copper(II) and differ only for the presence of the ethylmorpholine group.

Fungi can strongly acidify their immediate soil environment and can cause a change in the equilibrium of soil carbonates. The Tuber melanosporum brule is an interesting biological model for studying soil reaction (pH) and decarbonation–recarbonation soil processes associated with ectomycorrhizal plants and soil fauna communities. Over the past 10 years ,we have observed that (1) a high concentration of active carbonate and exchangeable Ca2+ in the soil favors T. melanosporum fruiting body production and larger brules, (2) the amount of active carbonate is significantly higher and the total carbonate is significantly lower inside the T. melanosporum brule than outside the brule, (3) T. melanosporum ectomycorrhizae impact biodiversity and soil quality, and (4) the calciferous glands of Lumbricidae have an impact on soil reaction and carbonate availability in the brules. Here we propose new hypotheses on ectomycorrhizal fungal ecology, soil biology, and inorganic C soil sinks, suggesting that (1) the model that best explains the cause and effect of all brule observations is a feedback process; (2) this model assumes that T. melanosporum’s ability to modify soil properties has a direct impact on plant nutrition and degree of plant mycorrhization, and this hypothesis could have a considerable impact from the evolutionary standpoint of ectomycorrhizal fungi; and (3) the integrated action of T. melanosporum and/or other ectomycorrhizal fungal populations, and earthworms, could be of major importance in the cycling and sequestration of inorganic C in the soil.

Two new thiosemicarbazones, methyl pyruvate-hydrazinopyruvoylthiosemicarbazone (H2mpipt), pyridoxal-hydrazinopyruv-oylthiosemicarbazone (H2piript), and their common reaction intermediate, pyruvic acid thiosemicarbazone hydrazide (Hipt), have been synthesized and characterized using IR and NMR spectroscopic methods. The crystal structures of H2mpipt and Hipt·H2O have been determined by X-ray crystallographic methods. Both compounds form monoclinic crystals belonging to the space group P21/c with Z=4 (a=11.050(2), b=10.386(2), c=11.468(2) A, β=114.87(3) ° and a=7.476(1), b=15.359(3), c=8.367(1)A, β=114.43(3)°, respectively). The ligand H2mpipt reacts with [Cu(PPh3)Cl]4 and forms the Cu(I) complex [Cu(PPh3)2(H2mpipt)Cl]·CH3OH whose structure has been determined by X-ray crystallographic methods. The copper atom has a distorted tetrahedral coordination sphere involving a chlorine atom, the phosphorus atoms of the two PPh3 molecules and a sulfur atom of the H2mpipt moiety. The crystals of the complex are triclinic, space group P1, Z=2, a=18.331(2), b=10.025(2), c=13.697(2) A, α=72.17(2), β=97.77(2), γ=87.42(2)°. The configuration of H2mpipt in the complex is different from that of the free ligand. The 1H, 13C and 15N NMR spectra for H2piript are also discussed.

A series of di- and tri-nuclear iron hydrazone–hexacyanoferrate complexes have been prepared and characterized by vibrational and electronic spectroscopies, thermal analysis and by the thermally stimulated depolarisation current (TSDC) technique. The TSDC spectra, measured in the range 110–300 K, have confirmed the reorientation of (1) dipoles in the terminal aromatic radicals, belonging to the molecule and (2) water molecules, whenever they are present in the compound or are adsorbed on it. A fraction of water molecules is loosely bound to the compound and can be removed by pumping on the sample; the related dehydration and hydration kinetics have been analysed.

The synthesis, spectroscopic studies, x-ray crystal structure, and biological properties of the complex [Cu(H2L)(OH2)Cl]Cl (1) (H2L = pyridoxal thiosemicarbazone) are reported. The compound crystallizes in space group P2(1)/n, a = 12.128(2), b = 9.096(2), c = 13.592(2) A, beta = 108.65(2) degrees, U = 1420.7 A3, and Z = 4. The molecular structure consists of discrete cations [Cu(H2L)(OH2)Cl]+ and Cl- anions. Each copper atom is in an approximately square pyramidal environment involving the phenolic oxygen, the imine nitrogen, the sulphur, and a water oxygen in the equatorial positions, while a chlorine atom occupies the axial position. The structure of this complex is compared to that of the dimeric [(Cu(HL)(OH2))2]Cl2.2H2O (2) obtained under different experimental conditions, to that of a Co(III) complex with the same ligand [Co(HL)L].4.5H2O (3) and to that of the free ligand H2L, especially in relation to its biological activity. Compounds 1 and 2 have not antiviral action in vitro with respect to RNA viruses, show an inductive effect on Friend erythroleukemia cells (FLC), erythroid differentiation and a suppressive effect regarding FLC proliferation. Complex 3 and the free ligand do not have biological activity.

The synthesis and structural characterization by IR, ESR, 119 Sn and 57 Fe Mossbauer spectroscopy, X-ray powder diffraction, and TG and DSC methods of a new series of organotin hexacyanoferrates are reported.

Chiral porphyrins 1 and 2, bearing, respectively, four and two chains at the meso carbons, each one with a stereocentre at C-2 and a double bond at C-5, were functionalized to afford the corresponding thiosemicarbazonic derivatives 9–12 and the nickel(II) porphyrinato 13, compounds with potential antiviral, antibacterial and antitumour properties. To verify the biological activity of some of these products, assays of proliferation inhibition and apoptosis tests in vitro on human leukemic cell lines U937 were carried out for compounds 1, 6, 9 and 10.

Novel ligands were obtained by condensation of pyridoxal with thiosemicarbazides substituted with alkyl and aryl moieties on the aminic and/or hydrazinic nitrogen. The spectrophotometric characteristics of the various species are reported. The X-ray structure of two different dimethylthiosemicarbazones of pyridoxal — pyridoxal N1,N2-dimethylthiosemicarbazone monohydrate and pyridoxal N1,N1-dimethylthiosemicarbazone monohydrate — was determined. The change of methyl group position determines in the solid state strong differences which affect the ligand behavior of these compounds. In the first ligand, characterized by X-ray diffraction, the pyridoxal ring is in a zwitterion form, with the phenolic oxygen and the sulfur atoms in trans position to the iminic N atom. The second compound, with both methyl groups on the aminic nitrogen, shows the donor atoms SNO on the same side, making it potentially suitable for coordination to the metal. Biological studies have involved both inhibition of cell proliferation ...

This paper reports the syntheses and characterization of ethylmorpholine substituted citronellal thiosemicarbazone copper(II) and nickel(II) metal complexes. The compounds were characterized through elemental analyses and spectroscopic (IR, UV–Vis, NMR, MS) methods. The X-ray analysis of the two complexes shows that both Ni and Cu derivatives present a square planar coordination, where the coordinating homologous donor atoms bind in trans to each other. The compounds were tested for their biological activity after determination of their octanol–saline partition coefficients, followed by their radical scavenging properties. Eventually the complexes were tested for their proliferation inhibition on human histiocytic lymphoma U937 cell line. The GI 50 values resulted to be 2.3 μM for the copper derivative and 12.3 μM for the nickel derivative.

Two new compounds, chlorobis(methyl pyruvate thiosemicarbazone)copper(I), [Cu(Hmpt)2Cl] (A), and chlorobis(triphenylphosphine)(methyl pyruvate thiosemicarbazone)copper(I) toluene solvate (2/1), [Cu(PPh3)2(Hmpt)Cl]·0.5C7H8 (B) have been synthesized and characterized using spectroscopic studies and single-crystal X-ray diffraction methods at 293 K. Compound A crystallizes in space group C2/c, with a = 14.695(1), b = 13.775(1), c = 10.251(1) A, β = 113.38(1)°, V= 1904.7 A3; compound B crystallizes in space group P 1 , with a=17.871(7), b=10.681(2), c=11.695(7) A, α=74.90(1), β=86.65(4), γ=83.66(2)°, V=2141 A3. The crystal structures were solved by the heavy-atom method for A and by direct methods for B and refined to R values of 0.053 for both compounds. In A the copper and chlorine atoms lie on a crystallographic two-fold axis and the trigonal coordination around copper involves, besides chlorine, two sulfur atoms from two Hmpt molecules. In B the copper is tetrahedrally four-coordinated involving a chlorine atom, a sulfur atom from the Hmpt molecule and the phosphorus atoms of the two PPh3 molecules. In both compounds the ligand is neutral, monodentate through the sulfur atom and shows the configuration Z E Z about the C(2)N(3), C(1)N(2) and C(2)C(3) bonds (with respect to possible donating centres O(1), N(3) and S). The main vibrational bands are also reported and discussed.

A new silver-tin complex salt of formula [Ag(AsPh 3 ) 4 ] 2 [Sn 2 Ph 4 (NO 3 ) 4 (OH) 2 ]·2CH 3 CN has been synthesized by treating Ag(AsPh 3 ) 2 NO 3 with stoichiometric amounts of SnPh 3 NO 3 in acetone/acetonitrile. The crystal structure of the complex has been determined by X-ray diffraction. Of major interest is the dimeric structure of the anion with two tin atoms, related by a center of symmetry, linked through two bridging hydroxyl groups. In the demeric unit each tin is in a distorted pentagonal bipyramidal environment, being also bound to three nitrate oxygens and two phenyl carbons. In the cation the coordination geometry around the silver atom is slightly distorted tetrahedral.

The synthesis and structural characterization by IR, ESR, 119 Sn and 57 Fe Mossbauer spectroscopy, X-ray powder diffraction, and TG and DSC methods of a new series of organotin hexacyanoferrates are reported.

The reaction between pyrrolylmagnesiumbromide and (3 R )-(+)-citronellal produced porphyrin 1 with four chains at the meso carbons, each one bearing a stereogenic centre at C-2 and a double bond at C-5. 4′-Fluoro-phenyldipyrrylmethanebismagnesiumbromide 4 with (3 R )-(+)-citronellal gave rise to porphyrin 2 with two stereogenic chains.

In this paper the syntheses of new pyridoxal thiosemicarbazone copper(II) and cobalt(III) complexes with nitroprusside as a counterion and tests on the antileukemic activity of three of these complexes toward human cell lines U937 and CEM are reported. Nitroprusside was chosen in order to test if its ability to release NO can increase the biological activity already shown by these complexes. The compounds were characterized by spectroscopic and magnetic methods and by single-crystal X-ray diffraction.

New alpha-ketoglutaric acid thiosemicarbazone (H(3)ct) derivatives and their copper complexes were synthesized and characterized by analytical and spectroscopic (IR and NMR) methods. For two of the ligands, Me-H(3)ct and Allyl-H(3)ct, and for a complex, [Cu(Me-Hct)(OH(2))](n) x 2nH(2)O, the X-ray structures were also determined. In the latter the copper atom shows a 4 + 1 pyramidal coordination, a water oxygen appears in the apical position, and three of the basal positions are occupied by the SNO tridentate ligand and the fourth by a carboxylic oxygen of an adjacent molecule that gives rise to a polymeric chain. DNA binding constants were determined, and studies of thermal denaturation profiles and nuclease activity were also performed. Tests in vitro on human leukemia cell line U937 were carried out on cell growth inhibition, cell cycle, and apoptosis induction.