Browsing by Author "Keramidas, Anastasios D."

Article

Aerial Oxidation of a VIV-Iminopyridine Hydroquinonate Complex: A Trap for the VIV-Semiquinonate Radical Intermediate

Stylianou, Marios; Drouza, Chryssoula; Giapintzakis, Ioannis; Athanasopoulos, Georgios I.; Keramidas, Anastasios D. (2015)

The reaction of 2,5-bis[N,N′-bis(2-pyridyl-aminomethyl)aminomethyl]-p-hydroquinone (H2bpymah) with VO2+ salts in acetonitrile or water at a low pH (2.2-3.5) results in the isolation of [{VIV(O)(Cl)}2(μ-bpymah)], the ...

Article

Bis(hydroxylamino)triazines: High Selectivity and Hydrolytic Stability of Hydroxylamine-Based Ligands for Uranyl Compared to Vanadium(V) and Iron(III)

Hadjithoma, Sofia; Papanikolaou, Michael G.; Leontidis, Epameinondas; Kabanos, Themistoklis A.; Keramidas, Anastasios D. (2018)

The development of ligands with high selectivity and affinity for uranium is critical in the extraction of uranium from human body, radioactive waste, and seawater. A scientific challenge is the improvement of the selectivity ...

Article

Charge distribution in vanadium p-(hydro/semi)quinonate complexes

Drouza, Chryssoula; Keramidas, Anastasios D. (2007)

The known crystal structures of co-ordination compounds containing p-dioxolene ligands in the form of hydroquinone, semiquinone or quinone have been examined. A simple method is proposed to correlate the oxidation state ...

Article

Cobalt(II), nickel(II) and zinc(II) coordination chemistry of the N,N′-disubstituted hydroxylamine-(diamido) ligand, 3,3′-(hydroxyazanediyl)dipropanamide

Papanikolaou, Michael G.; Hadjithoma, Sofia; Miras, Haralampos N.; Keramidas, Anastasios D.; Kabanos, Themistoklis A. (2018)

Although directly relevant to metal mediated biological nitrification and the coordination chemistry of peroxide, the transition metal complexes of hydroxylamines and their functionalized variants remain mainly unexplored ...

Article

Controlled one pot synthesis of polyoxofluorovanadate molecular hybrids exhibiting peroxidase like activity

Nicolaou, Maria; Drouza, Chryssoula; Keramidas, Anastasios D. (2019)

Three unique mixed-valence polyoxofluorovanadate clusters have been synthesized through a facile preparation process. The structure of these clusters is controlled by the addition of organic ligands. Single-crystal X-ray ...

Article

Crystal structure of 4-bromobenzohydrazide

Ashiq, U.; Jamal, R. A.; Mahroof-Tahir, M.; Keramidas, Anastasios D.; Maqsood, Z. T.; Khan, K. M.; Tahir, M. N. (2008)

The title compound was synthesized and its crystal structure was determined by X-ray diffraction analysis. The compound is monoclinic, space group P21/a with Z = 4. The unit-cell dimensions are a = 12.287(2)Å, b = 3.8287(5)Å, ...

Article

Design and Assembly of Covalently Functionalised Polyoxofluorovanadate Molecular Hybrids

Nicolaou, Maria; Papanikolaou, Michael G.; Tsipis, Athanassios C.; Kabanos, Themistoklis A.; Keramidas, Anastasios D.; Sproules, Stephen; Miras, Haralampos N. (2018)

Abstract Mixed-valent polyoxometalate (POM) clusters are one of the most interesting host species, showing a wide range of structural features and properties. The facile preparation and functionalisation of a mixed-valent ...

Article

Donor atom electrochemical contribution to redox potentials of square pyramidal vanadyl complexes

Vlasiou, Manolis; Drouza, Chryssoula; Kabanos, Themistoklis A.; Keramidas, Anastasios D. (2015)

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 ...

Article

Electroluminescence by a Sm3+-diketonate-phenanthroline complex

Stathatos, Elias; Lianos, P.; Evgeniou, E.; Keramidas, Anastasios D. (2003)

The development of an organic light emitting diode (OLED) based on the use of Sm3+ complex as an emitting layer was investigated. The construction process also involved the use of poly(vinylcarbazole) (PVK) as the transporter ...

Article

Electroluminescence from a volatile europium complex

Stathatos, Elias; Panayiotidou, L.; Lianos, P.; Keramidas, Anastasios D. (2006)

Three new strongly chelating heterocyclic ligands containing pyridine, imidazole and triazine rings have been used to make ternary complexes of Europium(III) ions together with trifluoroacetylacetonate. The complex containing ...

Article

Enhanced photon harvesting in silicon multicrystalline solar cells by new lanthanide complexes as light concentrators

Katsagounos, G.; Stathatos, Elias; Arabatzis, N. B.; Keramidas, Anastasios D.; Lianos, P. (2011)

Four europium complexes with enhanced luminescent properties have been synthesized. Thin transparent films of the complexes were prepared on glass panes and then were examined as efficient luminescent solar concentrators ...

Book Chapter

EPR Methods Applied on Food Analysis

Drouza, Chryssoula; Spanou, Smaragda; Keramidas, Anastasios D. (2018)

An overview of the different methodologies developed so far for the investigation of paramagnetic species in foods is presented. Electron paramagnetic resonance spectroscopy (EPR), also known as electron spin resonance ...

Article

Factors Affecting Solution Properties of Vanadium(V) Compounds: X-ray Structure of β-cis-NH4[VO2(EDDA)]1

Crans, D. C.; Keramidas, Anastasios D.; Mahroof-Tahir, M.; Anderson, O. P.; Miller, M. M. (1996)

The solution properties of two isomeric forms of the V-EDDA complex (the symmetric α-cis and asymmetric β-cis) have been studied using multinuclear NMR spectroscopy. The isomerization constant of the aqueous equilibrium ...

Article

Geographical discrimination of pine and fir honeys using multivariate analyses of major and minor honey components identified by 1H NMR and HPLC along with physicochemical data

Karabagias, Ioannis K.; Vlasiou, Manos; Kontakos, Stavros; Drouza, Chryssoula; Kontominas, Michael G.; Keramidas, Anastasios D. (2018)

The objective of the present work was the geographical discrimination of the most common honeydew honeys produced in Greece, namely pine and fir, on the basis of sugar, free amino acid and organic acid content, determined ...

Article

Insulin-mimetic action of vanadium compounds on osteoblast-like cells in culture

Etcheverry, S. B.; Crans, D. C.; Keramidas, Anastasios D.; Cortizo, A. M. (1997)

Vanadium compounds mimic insulin actions in different cell types. The present study concerns the insulin-like effects of three vanadium(V) derivatives and one vanadium(IV) complex on osteoblast-like (UMR106 and MC3T3E1) ...

Article

Interaction of Chromium(III) with a N, N ′-disubstituted hydroxylamine-(diamido) ligand: A combined experimental and theoretical study

Tziouris, Petros A.; Tsiafoulis, Constantinos G.; Vlasiou, Manolis; Miras, Haralampos N.; Sigalas, Michael P.; Keramidas, Anastasios D.; Kabanos, Themistoklis A. (2014)

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)d ...

Article

Investigation of dioxygen activation by copper(II)–iminate/aminate complexes

Papanikolaou, Michael G.; Hadjithoma, Sofia; Chatzikypraiou, Dimitra S.; Papaioannou, Dionysios; Drouza, Chryssoula; Tsipis, Athanassios C.; Miras, Haralampos N.; Keramidas, Anastasios D.; Kabanos, Themistoklis A. (2018)

The activation of dioxygen by metal ions is critical in chemical and bio-chemical processes. A scientific challenge is the elucidation of the activation site of dioxygen in some copper metalloproteins, which is either the ...

Article

Investigation on uranyl interaction with bioactive ligands. Synthesis and structural studies of the uranyl complexes with glycine and N-(2-mercaptopropionyl)glycine

Keramidas, Anastasios D.; Rikkou, Maria P.; Drouza, Chryssoula; Raptopoulou, Catherine P.; Terzis, Aris; Pashalidis, Ioannis (2002)

Three new uranium(VI) compounds have been prepared with glycine (Hgly), N-(2-mercaptopropionyl)glycine (Hmpg) and 2,2′-dithiobis(N-propionylglycine) (tpg). The crystal structure of [UO2(Hgly)2Cl2] has been solved, revealing ...

Article

Is vanadate reduced by thiols under biological conditions? Changing the Redox potential of V(V)/V(IV) by complexation in aqueous solution

Crans, D. C.; Zhang, B.; Gaidamauskas, E.; Keramidas, Anastasios D.; Willsky, G. R.; Roberts, C. R. (2010)

Although dogma states that vanadate is readily reduced by glutathione, cysteine, and other thiols, there are several examples documenting that vanadium(V)-sulfur complexes can form and be observed. This conundrum has ...

Article

Model Investigations for Vanadium-Protein Interactions. Synthetic, Structural, and Physical Studies of Vanadium(III) and Oxovanadium(IV/V) Complexes with Amidate Ligands

Keramidas, Anastasios D.; Papaioannou, Agelos B.; Vlahos, Antonis T.; Kabanos, Themistoklis A.; Bonas, George; Makriyannis, Alexandros M.; Raptopoulou, Catherine P.; Terzis, Aris (1996)

3, C19H13N3O2SV, Mr = 398.34, monoclinic, P21/n, a = 12.1108(10) Å, b = 19.4439(18) Å, c = 7.2351(7) Å, β = 103.012(3)°, V = 1660.0(4) Å3, Z = 4, R = 0.0355, and Rw = 0.0376