Publications by authors named "Manolis Vlasiou"

Based on the strong binding and high selectivity properties of 2,6-bis[hydroxy(methyl)amino]-4-morpholino-1,3,5-triazine (Hbihyat) for [UO], novel binucleating ligands (BLs) ,',″,-((1,4-phenylenebis(oxy))bis(1,3,5-triazine-6,2,4-triyl))tetrakis(-methylhydroxylamine) (Hqtn), ,-bis(4,6-bis(hydroxy(methyl)amino)-1,3,5-triazin-2-yl)benzene-1,4-diamine (Hpdl), and ,-bis(4,6-bis(hydroxy(methyl)amino)-1,3,5-triazin-2-yl)ethane-1,2-diamine (Henl) were synthesized. Binuclear complexes formed by coordination of hard metal ions with Hqtn are thermodynamically more stable than their mononuclear analogues with Hbihyat due to the increase in entropy accompanying the formation of more chelate rings. Reaction of either Hqtn or Hpdl or Henl with [UO] and [VO] resulted in the isolation of the binuclear complexes [(UO)(μ-qtn)(HO)] (), [(VO)(μ-qtn)][PPh][PPh4] (), [(UO)(μ-pdl)(HO)(MeOH)] (), [(VO)(μ-pdl)][PPh] (), [(UO)(μ-enl)(HO)] (), and [(VO)(μ-enl)][PPh] ().

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Since the discovery of the anticancer properties of cis-platin the road for the development of less toxic and more specific metal ion based anticancer drugs has opened. Based on the low toxicity of V, Mo and Zn metal ions, their binuclear hydroquinonate complexes have been synthesized and their biological activity towards their anticancer properties on various cancerous and non-cancerous cell lines has been evaluated. The new complexes of Zn with the ligands 2,5-bis((bis(pyridin-2-ylmethyl)amino)methyl)benzene-1,4-diol (Hbpymah) and 2,2'-(((2,5-dihydroxy-1,4-phenylene)bis(methylene))bis((carboxymethyl)ammoniumdiyl))diacetate (Hbicah) have been synthesized and characterized by X-ray crystallography in solid state and H NMR in aqueous solution.

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Using UV-Vis, FT-IR, fluorescence spectroscopy and protein-ligand docking, the interactions between the zinc complexes with drug analogues and bovine serum albumin were investigated. In addition, considering the ubiquitous presence of zinc ions in the human system, we studied the interactions between this ion with hymecromone, dihydropyridine analogue, and acetamide, as well as the pH influence on these systems. The complexes were synthesized by interaction between the ligands and the Zn (II) ion in a 2:1 M ratio.

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Novel vitamin E chelate derivatives and their V complexes have been synthesized and characterized, and their anticancer properties have been evaluated. The new complexes have been designed to exhibit enhanced cytotoxicity by combining high lipophilicity with the properties of vanadium to induce the formation of reactive oxygen species (ROS). In particular, the β-tocopherol derivatives with iminodiethanol (β-tocDEA) and dipicolylamine (β-tocDPA) as well their V and V complexes, [VO(β-tocDEA] and [VO(β-tocDPA] have been synthesized and characterized by Nuclear Magnetic Resonance (NMR), Ultra Violet-Visible (UV-Vis) and Electron Paramagnetic Resonance (EPR) spectroscopies.

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Corrosiveness is one of the main drawbacks of using the iodide/triiodide redox couple in dye-sensitized solar cells (DSSCs). Alternative redox couples including transition metal complexes have been investigated where surprisingly high efficiencies for the conversion of solar to electrical energy have been achieved. In this paper, we examined the development of a DSSC using an electrolyte based on square pyramidal oxidovanadium(IV/V) complexes.

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A simple donor atom additivity relationship has been used to calculate the donor atom electrochemical contribution (DEC) of the Oac (acetylacetonate-enolic oxygen), OPh (phenolic oxygen), SPh (mercaptophenol sulfur), Nam (deprotonate amide nitrogen), Nim (imine nitrogen) and Npy (pyridine nitrogen) to the redox processes of the square pyramidal vanadyl complexes. The study focuses on the amidate vanadyl complexes because of (a) their biological interest and (b) the existence of data from plethora complexes studied in great details. The electrochemical contributions for the vanadyl oxidation and reduction processes increase following the same order, OPh~Oac(enolic) View Article and Find Full Text PDF

Reaction of hydroxylamine hydrochloride with prop-2-enamide in dichloromethane in the presence of triethylamine resulted in the isolation of the N,N'-disubstituted hydroxylamine-(diamido) ligand, 3,3'-(hydroxyazanediyl)dipropanamide (Hhydia). The ligand Hhydia was characterized by multinuclear NMR, high-resolution electrospray ionization mass spectrometry (ESI-MS), and X-ray structure analysis. Interaction of Hhydia with trans-[Cr(III)Cl2(H2O)4]Cl·2H2O in ethanol yields the ionization isomers [Cr(III)(Hhydia)2]Cl3·2H2O(1·2H2O) and cis/trans-[Cr(III)Cl2(Hhydia)2]Cl·2H2O (2·2H2O).

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