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Maurya MR, Uprety B, Avecilla F, Adão P, Kuznetsov ML, Costa Pessoa J. Solution Behaviour and Catalytic Potential towards Oxidation of Dopamine by Oxidovanadium(V) Complexes of Tripodal Tetradentate Ligands. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700342] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Mannar R. Maurya
- Department of Chemistry; Indian Institute of Technology Roorkee; 247667 Roorkee India
| | - Bhawna Uprety
- Department of Chemistry; Indian Institute of Technology Roorkee; 247667 Roorkee India
| | - Fernando Avecilla
- Departamento de Química Fundamental; Universidade da Coruña; Campus de A Zapateira 15071 A Coruña Spain
| | - Pedro Adão
- Centro de Química Estrutural; Instituto Superior Técnico; Universidade Lisboa; 1049-001 Lisboa Portugal
| | - Maxim L. Kuznetsov
- Centro de Química Estrutural; Instituto Superior Técnico; Universidade Lisboa; 1049-001 Lisboa Portugal
| | - J. Costa Pessoa
- Centro de Química Estrutural; Instituto Superior Técnico; Universidade Lisboa; 1049-001 Lisboa Portugal
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Maurya MR, Uprety B, Avecilla F, Adão P, Costa Pessoa J. Vanadium(V) complexes of a tripodal ligand, their characterisation and biological implications. Dalton Trans 2015; 44:17736-55. [PMID: 26399883 DOI: 10.1039/c5dt02716k] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of the tripodal tetradentate dibasic ligand 6,6'-(2-(pyridin-2-yl)ethylazanediyl)bis(methylene)bis(2,4-di-tert-butylphenol), H2L(1)I, with [V(IV)O(acac)2] in CH3CN gives the V(V)O-complex, [V(V)O(acac)(L(1))] 1. Crystallisation of 1 in CH3CN at ∼0 °C gives dark blue crystals of 1, while at room temperature it affords dark green crystals of [{V(V)O(L(1))}2μ-O] 3. Upon prolonged treatment of 1 in MeOH, [V(V)O(OMe)(MeOH)(L(1))] 2 is obtained. All three complexes were analysed by single-crystal X-ray diffraction, depicting a distorted octahedral geometry around vanadium. In the reaction of H2L(1) with V(IV)OSO4 partial hydrolysis of the tripodal ligand results in the elimination of the pyridyl fragment of L(1) and the formation of H[V(V)O2(L(2))] 4 containing the ONO tridentate ligand 6,6'-azanediylbis(methylene)bis(2,4-di-tert-butylphenol), H2L(2)II. Compound 4, which was not fully characterised, undergoes dimerization in acetone yielding the hydroxido-bridged [{V(V)O(L(2))}2μ-(OH)2] 5 having a distorted octahedral geometry around each vanadium. In contrast, from a solution of 4 in acetonitrile, the dinuclear compound [{V(V)O(L(2))}2μ-O] 6 is obtained, with a trigonal bipyramidal geometry around each vanadium. The methoxido complex 2 is successfully employed as a functional catechol-oxidase mimic in the oxidation of catechol to o-quinone under air. The process was confirmed to follow a Michaelis-Menten type kinetics with respect to catechol, the Vmax and KM values obtained being 7.66 × 10(-6) M min(-1) and 0.0557 M, respectively, and the turnover frequency is 0.0541 min(-1). A similar reaction with the bulkier 3,5-di-tert-butylcatechol proceeded at a much slower rate. Complex 2 was also used as a catalyst precursor for the oxidative bromination of thymol in aqueous medium. The selectivity shows quite interesting trends, namely when not using excess of the primary oxidizing agent, H2O2, the para mono-brominated product corresponds to ∼93% of the products and no dibromo derivative is formed.
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Affiliation(s)
- Mannar R Maurya
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee-247667, India.
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Machado I, Fernández M, Becco L, Garat B, Brissos R, Zabarska N, Gamez P, Marques F, Correia I, Costa Pessoa J, Gambino D. New metal complexes of NNO tridentate ligands: Effect of metal center and co-ligand on biological activity. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2013.10.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Pessoa JC, Tomaz I. Transport of therapeutic vanadium and ruthenium complexes by blood plasma components. Curr Med Chem 2011; 17:3701-38. [PMID: 20846109 DOI: 10.2174/092986710793213742] [Citation(s) in RCA: 172] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 08/27/2010] [Indexed: 11/22/2022]
Abstract
Low molecular weight and high molecular weight metal ion binders present in blood plasma are shortly described. The binding of vanadium and ruthenium complexes by these components has received much attention, namely their interactions with human serum albumin and transferrin, and these studies are critically reviewed. The influence of the protein binding on the bioavailability of the prospective drugs, namely on the transport by blood plasma and uptake by cells is also discussed. It is concluded that vanadium compounds are mainly transported in blood by transferrin, but that no study has properly addressed the influence of albumin and transferrin in the vanadium uptake by cells. Ruthenium complexes bind strongly to HSA, most likely at the level of His residues, leading to the formation of stable adducts. If the kinetics of binding to this protein is fast enough, probably they are mainly transported by this serum protein. Nevertheless, at least for a few Ru(III)-complexes, hTf seems to play an active role in the uptake of ruthenium, while HSA may provide selectivity and higher activity for the compounds due to an enhanced permeability effect.
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Affiliation(s)
- J Costa Pessoa
- Centro de Química Estrutural, Instituto Superior Técnico, TU Lisbon, Av. Rovisco Pais, 1049-001, Lisbon, Portugal.
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Maurya MR, Khan AA, Azam A, Kumar A, Ranjan S, Mondal N, Pessoa JC. Dinuclear Oxidovanadium(IV) and Dioxidovanadium(V) Complexes of 5,5â²-Methylenebis(dibasic tridentate) Ligands: Synthesis, Spectral Characterisation, Reactivity, and Catalytic and Antiamoebic Activities. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900677] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
Lycotoxin I and Lycotoxin II are natural anti-microbial peptides that were identified in the venom of the Wolf Spider Lycosa carolinensis. These peptides were found to be potent growth inhibitors for bacteria (Escherichia coli) and yeast (Candida glabrata) at micromolar concentrations. Recently, shortened analogues of LycoI and LycoII have been reported to have decreased haemolytic effects. A shorter Lyco-I analogue studied, LycoI 1-15 (H-IWLTALKFLGKHAAK-NH2), was active only above 10 microM, but was also the least haemolytic. On the basis of these findings, we became interested in obtaining a deeper insight into the membrane activity of LycoI 1-15, as this peptide may represent the first major step for the future development of selective, i.e. non-haemolytic, Lycotoxin-based antibiotics. The interaction of this peptide with liposomes of different composition was studied by microcalorimetry [differential scanning calorimetry (DSC) and isothermal titration calorimetry (ITC)] and CD. The results obtained from the calorimetric and spectroscopic techniques were jointly discussed in an attempt to further understand the interaction of this peptide with model membranes.
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Affiliation(s)
- R Adão
- CIQ (UP), Department of Chemistry, Faculty of Sciences, University of Porto, P-4169-007 Porto, Portugal
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Capelo JL, Galesio MM, Felisberto GM, Vaz C, Pessoa JC. Micro-focused ultrasonic solid-liquid extraction (muFUSLE) combined with HPLC and fluorescence detection for PAHs determination in sediments: optimization and linking with the analytical minimalism concept. Talanta 2005; 66:1272-80. [PMID: 18970118 DOI: 10.1016/j.talanta.2005.01.046] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Revised: 01/07/2005] [Accepted: 01/21/2005] [Indexed: 11/18/2022]
Abstract
Analytical minimalism is a concept that deals with the optimization of all stages of an analytical procedure so that it becomes less time, cost, sample, reagent and energy consuming. The guide-lines provided in the USEPA extraction method 3550B recommend the use of focused ultrasound (FU), i.e., probe sonication, for the solid-liquid extraction of Polycyclic Aromatic Hydrocarbons, PAHs, but ignore the principle of analytical minimalism. The problems related with the dead sonication zones, often present when high volumes are sonicated with probe, are also not addressed. In this work, we demonstrate that successful extraction and quantification of PAHs from sediments can be done with low sample mass (0.125g), low reagent volume (4ml), short sonication time (3min) and low sonication amplitude (40%). Two variables are here particularly taken into account for total extraction: (i) the design of the extraction vessel and (ii) the solvent used to carry out the extraction. Results showed PAHs recoveries (EPA priority list) ranged between 77 and 101%, accounting for more than 95% for most of the PAHs here studied, as compared with the values obtained after soxhlet extraction. Taking into account the results reported in this work we recommend a revision of the EPA guidelines for PAHs extraction from solid matrices with focused ultrasound, so that these match the analytical minimalism concept.
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Affiliation(s)
- J L Capelo
- Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
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Pessoa JC, Correia I, Galvão A, Gameiro A, Felix V, Fiuza E. Enantioselectivity in Ni(ii) Schiff-base complexes derived from amino-acids and (S)-o-N-(N-benzylprolyl)aminobenzophenone. Molecular structure of several chiral Ni(ii) Schiff-base complexes, circular dichroism and molecular mechanics studies. Dalton Trans 2005:2312-21. [PMID: 15962053 DOI: 10.1039/b503786g] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Several Ni(II) complexes derived from (S)-o-N-(N-benzylprolyl)aminobenzophenone ((S)-BBP) and amino acids of general formula [Ni((S)-BBP-L-(or D-)-aa)] were prepared. The crystal and molecular structures of [Ni((S)-BBP-Gly)], [Ni((S)-BBP-L-Ser)] and [Ni((S)-BBP-L-aaIm)](aaIm =L-2-amino-3-(imidazol-1-yl)propanoate were determined by X-ray diffraction analysis. In the three complexes the nickel atoms display a square-planar coordination and the overall structure around the metal indicates that the entire Schiff-base ligands form quite rigid frameworks. Molecular mechanics calculations were carried out for complexes [Ni((S)-BBP-Gly)], [Ni((S)-BBP-Ser)] and [Ni((S)-BBP-aaIm)] containing either the L- or D-amino acid forms, and the factors controlling the stereoselectivity are discussed. Several other [Ni((S)-BBP-L-aa)] complexes are also prepared and their circular dichroism spectra in solution and of the solids dispersed in KBr disks are measured and discussed. In agreement with other studies in solution with similar [Ni((S)-BBP-aa)] complexes, the Cotton effects for the bands with lambda(max) at 520--530 nm are positive when the amino acids have the L-configuration at the alpha-carbon. The same is observed in this work for the solid-state CD spectra of all compounds.
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Affiliation(s)
- J Costa Pessoa
- Centro Química Estrutural, Departamento de Engenharia Química, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
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Serro AP, Bastos M, Pessoa JC, Saramago B. Bovine serum albumin conformational changes upon adsorption on titania and on hydroxyapatite and their relation with biomineralization. ACTA ACUST UNITED AC 2004; 70:420-7. [PMID: 15293315 DOI: 10.1002/jbm.a.30096] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The biocompatibility of implant materials used for substitution of bone tissue depends on its ability to induce the deposition of a hydroxyapatite layer when in contact with body fluids. In previous work, some of the authors found that bovine serum albumin (BSA) promotes calcium phosphate deposition if preadsorbed on hydroxyapatite and retards precipitation if preadsorbed on titania. In the present study, we investigated the adsorption of BSA upon particles of titania and hydroxyapatite in order to understand the different role played by the protein on the mineralization of both biomaterials. The adsorption isotherms were determined and the structural changes induced by adsorption at different surface coverages were investigated by circular dichroism spectroscopy and differential scanning microcalorimetry. At low surface coverages, the adsorbed BSA molecules lost part of their alpha-helix content. However, at high surface coverages, corresponding to the plateau values of the adsorption isotherms, the BSA molecules did not undergo structural rearrangements upon adsorption. In the latter circumstances, the availability of BSA calcium binding sites, which should be responsible for inducing mineralization, depends on the electrostatic interactions between BSA and the sorbent surface. A possible explanation for the different mineralization behavior of hydroxyapatite and titania is advanced.
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Affiliation(s)
- A P Serro
- Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
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Abstract
The equilibria in the system VO2+ +oxidized glutathione in aqueous solution have been studied in the pH range 2-11 by a combination of pH potentiometry and spectroscopy (EPR, visible absorption and circular dichroism). The results of the various methods are self-consistent and the equilibrium model includes the species MLH4, MLH3, MLH2, MLH, ML, MLH(-1), MLH(-2) and several hydrolysis products (where H4L denotes oxidized glutathione); individual formation constants and spectra are given. Plausible structures for each stoichiometry are discussed.
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Affiliation(s)
- J C Pessoa
- Centro Química Estrutural, Instituto Superior Técnico, Lisboa, Portugal.
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Costa Pessoa J, Cavaco I, Correia I, Costa D, Henriques R, Gillard R. Preparation and characterisation of new oxovanadium(IV) Schiff base complexes derived from salicylaldehyde and simple dipeptides. Inorganica Chim Acta 2000. [DOI: 10.1016/s0020-1693(00)00102-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
The synthesis, structure and spectroscopic properties of complexes with the formula [V(IV)O(dsal)2(H2O)], where Hdsal = salicylaldehyde, o-vanillin and 3-ethoxysalicylaldehyde, are presented. The crystal and molecular structures of [V(IV)O(o-van)2(H2O)] (1) (o-Hvan = o-vanillin = 3-methoxysalicylaldehyde) is studied by single-crystal X-ray diffraction. Each molecule exhibits an octahedral geometry with the two o-van ligands coordinated cis to the V(IV)O2+ group. 1 is the first example of a structurally characterized vanadium complex involving O(aldehyde) as the donor atom and this enables a comparison between the bonding characteristics and the contributions of O(aldehyde), O(amide), O(carboxylate) and O(ketone) (in acetylacetone) to the parallel hyperfine coupling constant in VOL2 complexes.
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Affiliation(s)
- J C Pessoa
- Centro Química Estrutural, Instituto Superior Tecnico, Lisbon, Portugal.
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Kiss T, Petrohán K, Buglyó P, Sanna D, Micera G, Costa Pessoa J, Madeira C. Oxovanadium(IV)-Promoted Peptide-Amide Deprotonation in Aqueous Solution. Inorg Chem 1998. [DOI: 10.1021/ic9802202] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- T. Kiss
- Department of Inorganic and Analytical Chemistry, Jozsef Attila University, P.O. Box 440, H-6701 Szeged, Hungary
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Borges C, Caetano C, Costa Pessoa J, Figueiredo M, Lourenço A, Gomes MM, Silva T, Veiga J. Monitoring the removal of soluble salts from ancient tiles by ion chromatography. J Chromatogr A 1997. [DOI: 10.1016/s0021-9673(97)00175-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Costa Pessoa J, Luz S, Gillard R. Oxovanadium(IV) complexes with peptides with non-coordinating side chains; Evidence for nitrogen amide coordination. J Inorg Biochem 1995. [DOI: 10.1016/0162-0134(95)97700-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Costa Pessoa J, Luz S, Gillard R. Oxovanadium(IV) and amino acids—VIII. l-histidine derivatives and related ligands: A spectroscopic study. Polyhedron 1995. [DOI: 10.1016/0277-5387(94)00424-d] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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de C. T. Carrondo MAAF, Duarte MTLS, Pessoa JC, Silva JAL, da Silva JJRF, Vaz MCTA, Vilas-Boas LF. Bis-(N-hydroxy-iminodiacetate)vanadate(IV), a synthetic model of ‘amavadin’. ACTA ACUST UNITED AC 1988. [DOI: 10.1039/c39880001158] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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