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Background: Systemic lupus erythematosus (SLE) may result in great impact on patients' quality of life, social relationships, and work productivity. The use of patient-reported outcome measures (PROMs) in routine care could help capture disease burden to guide SLE management and optimize disease control. We aimed to explore the current situation, appropriateness, and feasibility of PROMs to monitor patients with SLE in routine care, from healthcare professionals' and patients' perspectives., Methods: A scientific committee developed a Delphi questionnaire, based on a focus group with patients and a literature review, including 22 statements concerning: 1) Use of PROMs in routine care (n = 2); 2) PROMs in SLE management (n = 13); 3) Multidisciplinary management of patients with SLE (n = 4), and 4) Aspects on patient empowerment (n = 3). Statements included in Sects. 2-4 were assessed from three perspectives: current use, appropriateness, and feasibility (with currently available resources). For each statement, panellists specified their level of agreement using a 7-point Likert scale. A consensus was reached when ≥ 70% of the panellists agreed (6,7) or disagreed (1,2) on each statement., Results: Fifty-nine healthcare professionals and 16 patients with SLE participated in the Delphi-rounds. A consensus was reached on the value of PROMs to improve SLE management (83%) and the key role of healthcare professionals (77%) and the need for a digital tool connected to the electronic medical record (85%) to promote and facilitate PROMs collection. PROMs most frequently used in clinical practice are pain (56%), patient's global assessment (44%) and fatigue (39%), all on visual analogue scales. Panellists agreed on the need to implement multidisciplinary consultation (79%), unify complementary tests (88%), incorporate pharmacists into the healthcare team (70%), and develop home medication dispensing and informed telepharmacy programmes (72%) to improve quality of care in patients with SLE. According to panellists, patient associations (82%) and nurses (80%) are critical to educate and train patients on PROMs to enhance patient empowerment., Conclusions: Although pain, fatigue, and global assessment were identified as the most feasible, PROMs are not widely used in routine care in Spain. The present Delphi consensus can provide a road map for their implementation being key for SLE management., (© 2024. The Author(s).)

Mixed divalent Cu, Co, Ni and Zn complexes containing the new sulfonamide ligand N-(2-(pyridin-2-yl)ethyl)quinoline-8-sulfonamide (HQSEP) were prepared and characterized by physico-chemical techniques. The tetracoordinate [Cu(QSEP)X] [X = Br (1), Cl (2)] compounds present a seesaw geometry (τ 4  = 0.56 (1) and 0.50 (2)). The Cu(II) in the [Cu(QSEP)(NO 3 )(MeOH)] (3) complex is five coordinate with a slightly distorted SP geometry (τ = 0.11). The [M(QSEP)(benz)] [M = Cu(II) (4), Ni(II) (5), Co(II) (6) and Zn(II) (7); benz = benzoate] compounds are configurationally isotypic. The coordination geometries of the M(II) ions can be best described as distorted SP (τ = 0.29, 0.15, 0.34 and 0.18 for 4, 5, 6 and 7, respectively). The interaction of the compounds with CT-DNA was studied by different techniques. Notably, these studies indicated that the tetracoordinate complexes (1 and 2) present higher DNA affinity than pentacoordinate compounds (3-7). In line with the Irving-Williams order of stability, 5 presented higher propensity for DNA binding than 6. Interestingly, the cleavage activity of 1-4 in the presence of ascorbate/H 2 O 2 follows the same trend as that found for DNA binding affinity, being the tetracoordinate 1 and 2 more effective as nucleases than the five coordinate 3 and 4. Also, the DNA cleavage reaction mechanism was investigated. DNA cleavage experiments upon irradiation indicated the important role of the aromatic nature of the coligand in the photocleavage activity of 1-4. Finally, the interaction of the compounds with bovine serum albumin (BSA) was studied and the binding constants were calculated., (Copyright © 2019. Published by Elsevier Inc.)

Thiosemicarbazones (TSCs), and their copper derivatives, have been extensively studied mainly due to the potential applications as antitumor compounds. A part of the biological activity of the TSC-Cu II complexes rests on their reactivity against cell reductants, as glutathione (GSH). The present paper describes the structure of the [Cu(PTSC)(ONO 2 )] n compound (1) (HPTSC=pyridine-2-carbaldehyde thiosemicarbazone) and its spectroscopic and magnetic properties. ESI studies performed on the reaction of GSH with 1 and the analogous [{Cu(PTSC*)(ONO 2 )} 2 ] derivative (2, HPTSC*=pyridine-2-carbaldehyde 4N-methylthiosemicarbazone) show the absence of peaks related with TSC-Cu-GSH species. However GSH-Cu ones are detected, in good agreement with the release of Cu I ions after reduction in the experimental conditions. The reactivity of 1 and 2 with cytochrome c and myoglobin and their activities against HT-29 and SW-480 colon carcinoma cell lines are compared with those shown by the free HPTSC and HPTSC* ligands., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Four ternary complexes, [Cu(L1)2(bipy)] (1) [HL1 = N-(6-chlorobenzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide], [Cu(L2)2(bipy)] (2) [HL2 = N-(benzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide], [Cu(L3)2(bipy)]·1/2H2O (3) [HL3 = N-(5,6-dimethylbenzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide] and [Cu(L4)2(bipy)] (4) [HL4 = N-(5,6-dimethylbenzo[d]thiazol-2-yl)benzenesulfonamide], were prepared and then characterized by X-ray crystallography, spectroscopy and magnetic measurements. Whereas the molecular structure of 1 and 2 consists of a discrete monomeric copper(II) species with a distorted square planar geometry, that of 3 and 4 consists of two independent molecules. In 3, both molecules present a different coordination geometry (distorted square planar and distorted square pyramidal) while in 4 they have an identical coordination environment (distorted square planar). The propensity for binding of 1-4 to calf thymus DNA was studied by thermal denaturation, viscosimetry, and fluorescence measurements. Results indicated that the N-sulfonamide derivative plays an important role in governing the type of interaction with DNA. The ability of the complexes to cleave DNA was studied in vitro with ascorbate activation and was tested by monitoring the expression of the yEGFP gene containing the RAD54 reporter. Moreover, their antiproliferative activity was verified in two cellular models: yeast and human tumor cells in culture. Their DNA cleavage efficiency at the cellular level was found to be: 1 < 3 ~ 4 < 2. The higher propensity of 2 for inflicting DNA damage was related with its higher binding affinity to DNA. The biological studies carried out with human tumor cells, colon adenocarcinoma Caco-2 cells and leukemia Jurkat T lymphocytes confirmed that the compounds produce cell death mainly by apoptosis, the complex 2 being the most effective.

Ternary copper(II) complexes [Cu(NST)2(phen)] (1) and [Cu(NST)2(NH3)2]·H2O (2) [HNST=N-(4,5-dimethylthiazol-2-yl)naphthalene-1-sulfonamide] were prepared and characterized by physico-chemical techniques. Both 1 and 2 were structurally characterized by X-ray crystallography. The crystal structures show the presence of a distorted square planar CuN4 geometry in which the deprotonated sulfonamide, acting as monodentate ligand, binds to the metal ion through the thiazole N atom. Both complexes present intermolecular π-π stacking interactions between phenanthroline rings (compound 1) and between naphthalene rings (compound 2). The interaction of the complexes with CT DNA was studied by means of thermal denaturation, viscosity measurements and fluorescence spectroscopy. The complexes display good binding propensity to the calf thymus DNA giving the order: 1>2. Complex 1, which has a higher capability for binding to DNA, showed better nuclease activity than 2 in the presence of ascorbate/H2O2. Both the kinetics and the mechanism of the DNA cleavage reaction were investigated. Furthermore, complex 1 showed efficient photo-induced DNA cleavage activity on irradiation with UV light in the absence of any external reagent. The UV light induced DNA cleavage follows a photo-redox pathway with generation of hydroxyl radicals as reactive species. In addition, the cytotoxic properties of both complexes (1 and 2) were evaluated in human cancer cells (HeLa, Caco-2 and MDA-468). The low IC50 values, in particular those against Caco-2, have indicated that the compounds can be considered as promising chemotherapeutic agents., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The interaction of the Cu(II) drugs CuL(NO(3)) and CuL'(NO(3)) (HL is pyridine-2-carbaldehyde thiosemicarbazone and HL' is pyridine-2-carbaldehyde 4N-methylthiosemicarbazone, in water named [CuL](+) and [CuL'](+)) with [poly(dA-dT)](2), [poly(dG-dC)](2), and calf thymus (CT) DNA has been probed in aqueous solution at pH 6.0, I = 0.1 M, and T = 25 degrees C by absorbance, fluorescence, circular dichroism, and viscosity measurements. The results reveal that these drugs act as groove binders with [poly(dA-dT)](2), with a site size n = 6-7, whereas they act as external binders with [poly(dG-dC)](2) and/or CT-DNA, thus establishing overall electrostatic interaction with n = 1. The binding constants with [CuL'](+) were slightly larger than with [CuL](+). The title compounds display some cleavage activity in the presence of thiols, bringing about the rupture of the DNA strands by the reactive oxygen species formed by reoxidation of Cu(I) to Cu(II); this feature was not observed in the absence of thiols. Mutagenic assays performed both in the presence and in the absence of S9 mix, probed by the Ames test on TA 98, TA 100, and TA 102, were negative. Weak genotoxic activity was detected for [CuL](+) and [CuL'](+), with a significative dose-response effect for [CuL'](+), which was shown to be more cytotoxic in the Ames test and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assays. Methylation of the terminal NH(2) group enhances the antiproliferative activity of the pyridine-2-carbaldehyde thiosemicarbazones.

A series of compounds containing the nitrobenzene and sulfonamido moieties were synthesized and their leishmanicidal effect was assessed in vitro against Leishmaniainfantum promastigotes. Among the compounds evaluated, the p-nitrobenzenesulfonamides 4Aa and 4Ba, and the p-nitroaniline 5 showed significant activity with a good selectivity index. In a Balb/c mice model of L. Infantum, administration of compounds 4Aa, 4Ba or 5 (5mg/kg/day for 10 days, injected ip route) led to a clear-cut parasite burden reduction (ca. 99%). In an attempt to elucidate their mechanism of action, the DNA interaction of 4Aa and 5 was investigated by means of viscosity studies, thermal denaturation and nuclease activity assay. Both compounds showed nuclease activity in the presence of copper salt. The results suggest that compounds 4Aa, 4Ba and 5 represent possible candidates for drug development in the therapeutic control of leishmaniasis.

We report herein the synthesis of a novel tetracationic tris(2,2'-bipyridine) ligand 4. We show that this ligand metalated with copper(II), and in the presence of ascorbate as a reducing agent, strongly damages pUC18 plasmid DNA. Copper complex formation was demonstrated by ESI-MS (electrospray ionization-mass spectrum) at a 1:3 ligand to metal ratio. Binding of both 4 and its copper(II) complex to CT-DNA (calf thymus DNA) was characterized by viscosimetry, thermal denaturation and fluorescence-based competition assays. The viscosimetric data indicated that 4 and its copper(II) complex bind DNA through partial intercalation and thermal denaturation studies revealed a significant increase of duplex DNA stability in the presence of these species (DeltaT(m)=16.4 and 18.3 degrees C, respectively). Moreover, 4 and its copper(II) complex were found to effectively compete with ethidium bromide for the intercalative binding sites of DNA. Overall, the copper(II)-4 complex constitutes a very efficient DNA cleaving agent in the presence of ascorbate. Experiments with scavengers further suggest that the generation of Cu(I), hydrogen peroxide, superoxide, hydroxyl radical and singlet oxygen-like species contributes to the DNA breakage induced by the Cu(II) complex of 4.

The complex [Cu(N9-ABS)(phen)2].3.6H2O, H2N9-ABS = N-(9H-purin-6-yl)benzenesulfonamide and phen = 1,10-phenanthroline, has been synthesized and then characterized with the aid of X-ray diffraction, analytical, and spectroscopic techniques. The geometry of Cu(II) is distorted square pyramidal with the equatorial positions occupied by three N atoms from two phenantroline molecules and one N atom from the adenine ring of the sulfonamide ligand. The interaction of the complex with DNA was studied by means of viscosity measurements and fluorescence spectroscopy. The results pointed to a classic intercalation of the complex between the DNA base pairs. The complex was found to be a very efficient agent of plasmid DNA cleavage in the presence of ascorbate. Both the kinetics and the mechanism of the cleavage reaction were studied. In addition, the cytotoxic properties of the complex were evaluated in human Jurkat T and Caco-2 cell lines. The cytotoxicity of the compound was higher than that of the reference ([Cu(phen)2]2+). The mechanism and type of cell death induced by the compound was determined by flow cytometry and Hoechst dye staining. The compound demonstrated a significant ability to induce cell death by apoptosis. The apoptosis induced by [Cu(N9-ABS)(phen)2].3.6H2O was associated with an increase in p53 protein levels while those of Bcl-2 were reduced.

Three doubly-bridged, trinuclear copper(II) compounds with hydroxo and carboxylato bridges, (infinity)(1)[Cu(3)(L1)(2)(mu-OH)(2)(mu-propionato)(2)](1), [Cu(3)(L2)(2)(mu-OH)(2)(mu-propionato)(2)(DMF)(2)] (2) and (infinity)(1){[Cu(3)(L3)(2)(mu-OH)(2)(mu-propionato)(2)]} [Cu(3)(L3)(2)(mu-OH)(2)(mu-propionato)(2)(DMF)(2)]} (3) [HL1=N-(pyrid-2-ylmethyl)benzenesulfonylamide, HL2=N-(pyrid-2-ylmethyl)toluenesulfonylamide, HL3=N-(pyrid-2-ylmethyl)naphthalenesulfonylamide], have been synthesized and characterized. 1 is built from [Cu(3)(L1)(2)(mu-OH)(2)(mu-propionato)(2)] clusters. Each unit contains three copper(II) with two different coordination environments: the terminal centers are square-base pyramidal whereas the central copper is square planar. 2 presents a similar square-base pyramidal geometry in the terminal centers, but the central copper is six-coordinate. 3 shows an unusual 1D coordination polymer comprised of two distinct building blocks: one similar to that found in 1 and the other similar to that found in 2. The magnetic susceptibility measurements (2-300K) reveal a ferromagnetic interaction between the Cu(II) ions with J values of 76.0, 55.0, and 48.0cm(-1) for 1, 2, and 3, respectively. Emission spectroscopy, thermal denaturation, viscosimetry and cyclic voltammetry show an interaction of the complexes with DNA through the sugar-phosphate backbone. All three Cu(II) complexes were found to be very efficient agents of plasmid DNA cleavage in the presence of ascorbato or mercaptopropionic acid. Both the kinetics and the mechanism of the cleavage reaction have also been examined.

Two copper(II) complexes with a benzothiazolesulfonamide ligand, [Cu(L)2(py)2] (1) and [Cu(en)2(L)2] (2) [HL is N-2-(4-methylbenzothiazole)toluenesulfonamide, py is pyridine, en is ethylenediamine], were prepared and then characterized with the aid of X-ray crystallography and spectroscopy. Whereas the copper(II) ion in 1 presents a square-planar geometry, in 2 it has a distorted octahedral environment. In addition, although the ligand is monodentate in both complexes, it exhibits different coordination behavior in each, interacting through the benzothiazole nitrogen atom in 1 and through the sulfonamide nitrogen atom in 2. The propensity for binding of 1 and 2 to calf thymus DNA was studied by thermal denaturation, viscosimetry, and cyclic voltammetry. The ability of the complexes to cleave DNA was studied in vitro through ascorbate activation and was tested by monitoring the expression of the yEGFP gene containing the RAD54 reporter. Moreover, their antiproliferative activity was verified in two cellular models: yeast and human tumor cells in culture. While 1 was found to be the more active cleaving agent in vitro, 2 showed a higher propensity for inflicting DNA damage at the cellular level. The biological studies carried out with human tumor cells, namely, colon adenocarcinoma Caco-2 cells (HTB-37) and leukemia Jurkat T lymphocytes (TIB-152), confirmed that both compounds inhibit the growth of these cell lines, although 2 is more effective. This difference is associated with the latter compound's greater ability to induce cell death by apoptosis.

New complexes of formulae [Cu(HL(2))(H(2)O)(NO(3))](NO(3)) (1), [{Cu(L(1))(tfa)}(2)] (2), [{Cu(L(1))}(2)(pz)](ClO(4))(2) (3) and {[{Cu(L(1))}(2)(dca)](ClO(4))}(n) (4), where HL(1)=pyridine-2-carbaldehyde thiosemicarbazone, HL(2)=pyridine-2-carbaldehyde 4N-methylthiosemicarbazone, Htfa=trifluoroacetic acid (CF(3)COOH), pz=pyrazine (C(4)H(4)N(2)) and dca=dicyanamide [N(CN)(2)](-), have been synthesized and characterized. The crystal structures of these compounds are built up of monomers (1), dinuclear entities with the metal centers bridged through the non-thiosemicarbazone coligand (2 and 3) and 1D chains of dimers (4). In all the cases, square-pyramidal copper(II) ions are present, except for the square-planar ones in 3. Magnetic measurements show antiferromagnetic couplings in 2, 3 and 4. The susceptibility data were fitted by the Bleaney-Bowers' equation for copper(II) dimers derived from H=-2JS(1)S(2) being the obtained J/k values -4.8, -4.3 and -5.1K for compounds 2-4, respectively. The magnetic susceptibility of the already known [{Cu(HL(1))(tfa)}(2)](tfa)(2) compound has been also measured for the first time. The J/k value is -0.3K, lower than that in 2. The nuclease activity of 3 and 4 has been analyzed.

We have focused our interest on the tetrapyridoacridine ligand tetrapyrido[3,2-a:2',3'-c:3'',2''-h: 2''',3'''-j]acridine (tpac), as a model system for the preparation of novel copper-based artificial nucleases. The complex of copper(II)-tpac cleaves supercoiled pUC18 plasmid DNA in an oxidative manner by photoactivation with visible light, exhibiting maximum cleaving efficiency at 1:2 metal-ligand stoichiometric ratio. We propose an interaction of the copper-tpac complex with DNA through both major and minor grooves and a photocleavage mechanism via the formation of hydroxyl radicals and singlet oxygen or singlet oxygen-like species.

New copper(II) complexes with sulfonamide ligands have been prepared and characterized. Sulfonamide ligands were prepared through a reaction between 8-aminoquinoline and either 2-mesitylene (Hqmesa), 4-tert-butylbenzene (Hqtbsa), or alpha-toluene (Halphaqtsa) sulfonyl chlorides. The structural analysis carried out for complex [Cu(alphaqtsa)(2)] indicated that the local environment of the Cu(II) cation is between a square planar and a tetrahedral geometry, with stacking of the benzene rings of the sulfonyl ligands between neighbor molecules. Powder EPR spectra at room temperature gave rhombic spectra for the [Cu(alphaqtsa)(2)] and [Cu(qmesa)(2)] complexes and an axial spectrum for the [Cu(qtbsa)(2)] complex, probably due to the steric hindrance of the methyl groups. Complexes [Cu(alphaqtsa)(2)] and [Cu(qmesa)(2)] are artificial chemical nucleases that degrade DNA in the presence of sodium ascorbate. A study of the radical scavengers revealed that the ROS (reactive oxygen species) involved in the DNA damage were hydroxyl, singlet oxygen-like species, and superoxide anion.

The reaction of copper(II) sulfate, copper(II) chloride, 3,5-diacetylamino-1,2,4-triazole, and 3-acetylamino-5-amino-1,2,4-triazole in water yields green, plate-shaped crystals of [[{Cu3(mu3-OH(1/2))L(H2O)2Cl}2{mu-Cu(H2O)2Cl2}].12H2O]n (1), where L is a new triazole-derived macrocyclic ligand. The structure of 1 consists of heptanuclear (H)OCuII(3)-CuII-CuII(3)O(H) entities linked in pairs through symmetric mu3-O...H...O-mu3 hydrogen bonds to form a double-stranded one-dimensional network. A significant overall antiferromagnetic behavior has been observed for 1.

A flavonol iron(III) complex, [Fe(flavonolato)(2)Cl(MeOH)], has been prepared. The compound has been characterized by X-ray crystallography, spectroscopy, magnetism and electronic paramagnetic resonance (EPR) at X- and Q-band. The geometrical environment around the metal is best described as rhombic distorted octahedral. This distortion has also been inferred from the magnetic measurements and from the EPR spectra at different temperatures, E/D(rhombicity parameter) approximately 0.06. The DNA cleavage activity of the iron(III) complex with and without ascorbate/hydrogen peroxide is reported. Mechanisms of the oxidative cleavage have been proposed when DNA strand scission is performed both with and without ascorbate/hydrogen peroxide activation.

Copper(II) complexes of N-benzothiazolesulfonamides (HL1=N-2-(4-methylphenylsulfamoyl)-6-nitro-benzothiazole, HL2=N-2-(phenylsulfamoyl)-6-chloro-benzothiazole, and HL3=N-2-(4-methylphenylsulfamoyl)-6-chloro-benzothiazole) with ammonia have been synthesized and characterized. The crystal structures of the [Cu(L1)2(NH3)2].2MeOH, [Cu(L2)2(NH3)2], and [Cu(L3)2(NH3)2] compounds have been determined. Compounds and present a distorted square planar geometry. In both compounds the metal ion is coordinated by two benzothiazole N atoms from two sulfonamidate anions and two NH3 molecules. Complex is distorted square-pyramidal. The Cu(II) ion is linked to the benzothiazole N and sulfonamidate O atoms of one of the ligands, the benzothiazole N of another sulfonamidate anion, and two ammonia N atoms. We have tested the superoxide dismutase (SOD)-like activity of the compounds and compared it with that of two dinuclear compounds [Cu2(L4)2(OCH3)2(NH3)2] and [Cu2(L4)2(OCH3)2(dmso)2] (HL4=N-2-(phenylsulfamoyl)-4-methyl-benzothiazole). In vitro indirect assays show that the dimeric complexes are better SOD mimics than the monomeric ones. We have also assayed the protective action provided by the compounds against reactive oxygen species over Deltasod1 mutant of Saccharomyces cerevisiae. In contrast to the in vitro results, the mononuclear compounds were more protective to SOD-deficient S. cerevisiae strains than the dinuclear complexes.

Background: Data on long-term central nervous system (CNS) toxicity associated with efavirenz therapy are scarce, and risk factors remain largely unknown. We aimed to determine whether monitoring the plasma concentration of efavirenz could predict neuropsychiatric adverse events associated with long-term therapy with efavirenz., Methods: We performed a longitudinal study involving 17 consecutive human immunodeficiency virus (HIV)-infected subjects with virological suppression after at least 6 months of antiretroviral therapy with an efavirenz-containing regimen. Efavirenz plasma concentrations were measured at study entry and at different time points through an 18-month study period., Results: Median duration of efavirenz therapy before study entry was 18 months (range, 6-27 months). Ten (58.8%) of the patients experienced CNS-related adverse effects, ranging from insomnia and abnormal dreams to depression with suicidal ideation. In 4 (23.5%) of the cases, CNS toxicity led to efavirenz discontinuation. Mean (+/- standard deviation) plasma levels were higher for patients experiencing neuropsychiatric symptoms (5.10 +/- 2.15 microg/mL vs. 2.79 +/- 1.31 microg/mL; P = .024). A plasma level of 2.74 microg/mL had a sensitivity of 90.9% and specificity of 72% to predict CNS toxicity (area under the curve, 0.839; 95% confidence interval, 0.73-0.95; P < .0001). Patients having efavirenz plasma concentrations > 2.74 microg/mL at any time point of the study were 5.68 times more likely to experiencing CNS toxicity than were other patients (95% confidence interval, 1.97-16.37)., Conclusions: In patients with HIV infection receiving long-term therapy with efavirenz-containing antiretroviral regimens, CNS toxicity is related to efavirenz plasma levels. Patients achieving higher plasma levels are at increased risk of experiencing neuropsychiatric adverse events.

Three new monomeric Cu(II) complexes of 5-amino-3-pyridin-2-yl-1,2,4-triazole (Hapt), [Cu(Hapt)(H(2)O)(2)(SO(4))] (1), [Cu(Hapt)(2)(H(2)O)(NO(3))](NO(3)) (2), and [Cu(Hapt)(2)(NCS-N)](NCS).H(2)O (3), have been prepared and characterized by single crystal X-ray diffraction. One distorted [CuN(2)O(2)+O(')] square-pyramidal (1), one distorted [CuN(3)O+N(')+O(')] octahedral (2), and one distorted [CuN(4)+N(')] intermediate between square-pyramidal and trigonal-bipyramidal (3) coordination configuration were found and are suggested to be due to the chelating nature of the ligand, which interacts with Cu(II) through the N4(triazole) and N(pyridine) atoms. Spectral properties of these chelates are in accordance with the X-ray structural data. With ascorbate and H(2)O(2) activation, compound 2 exhibits higher nuclease activity than compound 1. The influence on the DNA cleavage process of different scavengers of reactive oxygen species: dimethyl sulfoxide (DMSO), tert-butyl alcohol, sodium azide, 2,2,6,6-tetramethyl-4-piperidone and superoxide dismutase enzyme (SOD), and of the minor groove binder distamycin, is also studied.

Copper(II) complexes of N-benzothiazolsulfonamides, [Cu(N-2-(5,6-dimethylbenzothiazole)toluenesulfonamidate)(2)(dmso)(2)] (1), [Cu(N-2-(6-chlorobenzothiazole)benzenesulfonamidate)(2)(dmso)(2)] (2) and [Cu(N-2-(6-chlorobenzothiazole)toluenesulfonamidate)(2)(dmso)(2)] (3) with interesting protective properties against superoxide radicals have been prepared. The compounds have been characterized by X-ray diffraction and their chemical properties have been studied by spectroscopic methods. The crystal structure of 1 shows that the copper(II) is surrounded by two benzothiazole N atoms from the sulfonamide ligands and two O atoms from the dimethylsulfoxide molecules in a square planar arrangement. The coordination polyhedron around copper(II) in 2 and 3 is distorted square pyramidal being the metal ion linked to benzothiazole N and sulfonamidate O atoms of the ligand and to two dimethylsulfoxide O atoms. The three complexes have a strong protective action over Delta sod1 mutant of Saccharomyces cerevisiae against reactive oxygen radicals derived from respiration and against those generated by hydrogen peroxide and menadione.

Two new mu-methoxo-bridged dinuclear copper(II) complexes with a N-substituted sulfonamide, [Cu(mu-OMe)(L)(NH(3))](2) (1) and [Cu(mu-OMe)(L)(DMSO)](2) (2) [HL, N-2-(4-methylbenzothiazole)benzenesulfonamide], have been prepared and characterized by single-crystal X-ray difraction analyses. Compound 1 crystallizes in the monoclinic space group C(2)/c with a=22.0678(18), b=7.9134(7), c=21.1186(18)A, beta=113.788(4) degrees and Z=8. Compound 2 crystallizes in the monoclinic space group C(2)/c with a=18.0900(10), b=9.5720(10), c=24.2620(10) A, beta=98.7120(10) degrees and Z=8. In both complexes the copper atoms have square-planar environments bridged by two oxygen atoms from methoxide groups. Magnetic susceptibility measurements indicate a very strong antiferromagnetic coupling between the copper(II) ions in both complexes (2J<-1000 cm(-1)). Electronic Paramagnetic Resonance (EPR) spectra of the two complexes both in solid and in solution are silent. 13C NMR spectra of the complexes in solid state have been studied. The complexes have been evaluated as model systems for the catechol oxidase enzyme using 3,5-di-tert-butylcatechol as the test substrate. Complex 2 is slightly more active than complex 1.

Mixed coordination compounds of Cu(II) with sulfonamides and 1,10-phenanthroline as ligands have been prepared and characterised. Single crystal structural determination of the complex [Cu(N-quinolin-8-yl-p-toluenesulfonamidate)(2)(phen)] shows Cu(II) ions are located in a highly distorted octahedral environment, probably as a consequence of the Jahn-Teller effect. The FT-IR and electronic paramagnetic resonance (EPR) spectra are also discussed. The mixed complexes prepared undergo an extensive DNA cleavage in the presence of ascorbate and hydrogen peroxide. Two of the complexes have higher nucleolytic efficiency than the bis(o-phenanthroline)copper(II) complex.

Copper-based transition metal complexes performing single- and double-strand scission of DNA have been studied. The dinuclear complexes [Cu(2)(L)(2)(OCH(3))(2)(NH(3))(2)] and [Cu(2)(L)(2)(OCH(3))(2)(DMSO)(2)] are more active than the corresponding mononuclear [Cu(L)(2)(py)(2)] (where HL= N-(4-methylbenzothiazol-2-yl)benzenesulfonamide), suggesting that the dinuclearity is an important factor in the oxidative cleavage of DNA. The cleavage efficiency of the complexes depends on the reducing agent used in the process, the tandem ascorbate/H(2)O(2) being the most efficient. PAGE analyses have shown that these complexes cleave DNA without sequence selectivity. The DNA degradation process takes place mainly by C1' oxidation, but C4' and C5' oxidations cannot be ruled out as minor pathways. These copper complexes preferably oxidize guanine under mild conditions, but under more drastic conditions the oxidation reactivity appears to be T>G>C>A, suggesting the intervention of hydroxyl radicals as active species.

Copper(II) ternary complexes based on the novel benzothiazole- N-sulfonamides, HL1 ( N-2-(4-methylbenzothiazole)benzenesulfonamide) and HL2 ( N-2-(6-nitrobenzothiazole)naphthalenesulfonamide) ligands, and pyridine have been synthesized and characterized. Complexes [Cu(L1)(2)(py)(2)] (1). and [Cu(L2)(2)(py)(2)] (2). were chemically characterized and their structures determined by means of single crystal X-ray analysis. In both compounds the Cu(II) ion is coordinated to four N atoms in a nearly square planar arrangement. The Cu-N bond distances are similar to those of Cu(2)Zn(2)SOD. The SOD mimetic activity of the complexes was determined both in vitro and in vivo. For determining the SOD-like activity of the complexes in vivo, we have developed a new method based on the complexes' protective effect on a delta sod1mutant of Saccharomyces cerevisiae against free radicals generated by hydrogen peroxide and menadione as well as free radicals produced in the cellular respiration process. The results have shown that complex 1 presents a protective action against oxidative stress induced by menadione or H(2)O(2) and that both complexes 1 and 2 protect against free radicals generated in cellular respiration.

New copper(II) complexes of the cyclic trinuclear type with 1,2,4-triazole ligands, [Cu(3)(mu(3)-OH)(aaat)(3)(H(2)O)(3)](NO(3))(2).H(2)O [Haaat = 3-acetylamino-5-amino-1,2,4-triazole] (1) and ([Cu(3)(mu(3)-OH)(aat)(3)(mu(3)-SO(4))].6H(2)O)(n) [Haat = 3-acetylamino-1,2,4-triazole] (2), have been prepared and characterized by X-ray crystallography and magnetic measurements. Compound 1, the first reported with the ligand (H)aaat, consists of discrete trinuclear cations, associated NO(3)(-) anions and lattice water molecules. Compound 2 consists of unusual chains of trinuclear units with a tridentate sulfato group linking the trimeric units and water molecules stabilizing the crystal lattice. In both complexes, 1 and 2, the trinuclear [Cu(3)(OH)L(3)] unit contains a pyramidal Cu(3)-mu(3)OH core, and an almost flat Cu(3)N(6) ring formed by the N,N-bridging triazolato groups. The Cu...Cu' intratrimeric distances are 3.35-3.37-3.39 A in 1 and 3.34-3.34-3.36 A in 2. The copper atoms are five-coordinated with a distorted square-pyramidal geometry. Magnetic measurements have been performed in the 1.9-300 K temperature range. In the high-temperature region (T > 90 K), experimental data could be satisfactorily reproduced by using an isotropic exchange model, H = -J(S(1)S(2) + S(2)S(3) + S(1)S(3)), with J = -194.6 cm(-1) and g = 2.08 for 1, and J = -185.1 cm(-1) and g = 2.10 for 2. The magnitude of the antiferromagnetic exchange in both complexes is discussed on the basis of their structural features by comparison with reported N,N-pheripherically bridged trinuclear systems. In order to fit the experimental magnetic data at low temperature, an antisymmetric exchange term, H(AS) = G(S(1)xS(2) + S(2)xS(3) + S(1)xS(3)), had to be introduced, with G = 27.8 (1) and 31.0 (2) cm(-1). Crystal data: C(12)H(27)Cu(3)N(17)O(14) (1) (MW = 824.13) crystallizes in the triclinic space group, P(-)1, Z = 2, with the cell dimensions a = 8.852(2) A, b = 11.491(3) A, c = 15.404(3) A, alpha = 70.43(3) degrees, beta = 75.11(2) degrees, gamma = 88.43(2) degrees, and V = 1423.8(5) A(3), D(calcd) = 1.922 g cm(-)(3); the final agreement values were R1 = 0.0822 and wR2 = 0.2300 for 4989 unique reflections. C(12)H(28)Cu(3)N(12)O(14)S (2) (MW = 787.14) crystallizes in the triclinic space group, P(-)1, Z = 2, with the cell dimensions a = 7.146(6) A, b = 14.26(1) A, c = 15.35(2) A, alpha = 109.0(9) degrees, beta = 93.6(9) degrees, gamma = 99.5(7) degrees, and V = 1448(2) A(3), D(calcd) = 1.806 g cm(-3); the final agreement values were R1 = 0.0628 and wR2 = 0.1571 for 3997 "observed" reflections.

Disulfiram is widely used in the treatment of chronic alcoholism. Adverse drug reactions with fatal outcome following disulfiram therapy are infrequent, and hepatic failure accounts for most of them. Since disulfiram is a cytochrome P450 (CYP450) enzyme system inhibitor, numerous interactions with several drugs metabolized in the liver have been reported. Like disulfiram, clarithromycin inhibits a CYP450 isoenzyme, but, despite its widespread use for the treatment of respiratory tract infections, no interactions with disulfiram have been described as yet. We report a case of fatal toxic epidermal necrolysis (Lyell disease) and fulminant hepatitis shortly after starting treatment with clarithromycin in a patient who was receiving disulfiram. This is the first case of such a severe dermatosis in a patient receiving either disulfiram or clarithromycin therapy. The temporal relationship between drug administration and clinical symptoms in this case suggests a probable interaction between the 2 drugs.

A new copper complex with N-quinolin-8-yl-p-toulenesulfonamide has been prepared and characterised. The compound crystallises in the triclinic system, space group P1, with a=13.457(3), b=15.067(5), c=18.589(3) A; alpha=112.05(2), beta=93.92(2), gamma=108.30(2) degrees and Z=4. The geometry of the Cu(II) ion is distorted square planar. The N-quinolin-8-yl-p-toulenesulfonamidate anion behaves as a bidentate ligand through the N(sulfonamidate)and N(quinoline) atoms. The complex does not cleave DNA in the presence of hydrogen peroxide.

A copper(II) complex of formula Cu(2)(stz)(4) (stz(-) = sulfathiazolato) has been synthesized and characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic system, space group P2(1)cn with a = 10.595(7) Å, b = 14.274(3) Å, c = 29.65(1) Å, and Z = 4. The structure consists of dinuclear copper(II) units which contain four sulfathiazolato ligands bridging the metal ions through a nonlinear NCN group. The copper atoms are four-coordinated, the chromophore being CuN(4). The Cu.Cu bond distance is 2.671(2) Å. Magnetic susceptibility data in the temperature range 7-300 K show the occurrence of intramolecular antiferromagnetic coupling with 2J = -61.5 cm(-1). This low exchange energy value has been analyzed and rationalized through extended Hückel calculations. EPR spectra at X- and Q-band frequencies show the signals corresponding to a dinuclear entity, being the zero-field splitting parameter, D = 0.230 cm(-1).