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Tiosemikarbazony : właściwości koordynacyjne w aspekcie aktywności biologicznej

Ostrowska M., Toporivska Y., Pyrkosz-Bulska M., Gumienna-Kontecka E.

Wiadomości Chemiczne

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2018

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[Z] 72, 7-8

449--467

EN

Thiosemicarbazones are considered to be potential therapeutics, because they possess a broad range of biological properties including antitumor, antimalarial and antimicrobial activity. Generally, the tiosemicarbazones coordinate to the metal centre by means of an (N,S) bidentate mode, and when an additional coordinating group is present, more diversified binding modes can occur such as a tridentate (X,N,S) coordination fashion. The stability of the metal complexes formed with the tiosemicarbazoness strongly depends on the character of the metal ion, the X-donor atom of the additional functional group and the position and type of the substituents at the tiosemicarbazones. The most prominent representative of this family is the α(N)-heterocyclic Triapine (3-aminopyridine- 2-carbaldehyde thiosemicarbazone; 3-AP), which is currently undergoing different phase-I and -II clinical trials as an antitumor agent, and demonstrates promising activity. Triapine is a very strong inhibitor of ribonucleotide reductase, the rate determining enzyme in the supply of deoxyribonucleotides for DNA synthesis required for cell proliferation. The mechanism of action involves most probably the formation of an iron(II)–Triapine complex, which reacts with molecular oxygen to result in the generation of reactive oxygen species. Subsequently, these reactive oxygen species are responsible for the quenching of the active-site tyrosyl radical of ribonucleotide reductase required for the enzymatic activity. As a result, the coordination chemistry of iron complexes of tiosemicarbazones has been receiving considerable attention. This review describes the coordination chemistry of tiosemicarbazones, in particular analogs of Triapine. The coordination compounds of d-block elements are discussed with respect to their bonding and structures. Several of complexes are mononuclear, with distorted tetrahedral, square planar, square pyramid or octahedral as their common geometries. The metal-binding ability of STSC at physiological pH was compared and shown. Further, various biological applications with emphasis an anticancer activity of the ligands/complexes are discussed in brief so as to indicate the importance of ligands under consideration.

2

Voltammetric Study of Interaction of Copper with Some Methyl-Substituted Ethylenediimine Compounds Using Nonlinear Least-Squares-Excel-Solver

Fotouhi L., Bahmanpour T., Ghasemi J., Dehghanpour S., Heravi M.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 3

483-489

EN

The complex formation of Cu2+ with some recently synthesized methyl-substituted ethylenediimines in binary dimethylformamide-ethanol mixtures was studied by differential pulse voltammetry. The stoichiometry and the stability of the complexes were determined by monitoring the increasing complex peak current against the ligand concentration using nonlinear least squares-Excel solver. In all studied cases, it was found that the stability of the resulting 1:1 complex decreases by increasing the amount of ethanol in the binary mixtures. The observed stability order is discussed in terms of the solvent binary mixtures and the nature of the substituted ethylenediimine structure.

3

Speciation and Spectra of Bromokojatoiron(III) Complexes in Aqueous Solutions

Šima J., Šípoš R., Izakovic M., Valigura D., Tarapeík P.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 12

1991-1999

EN

The formation of iron(III) complexeswith chelating bromokojate anions L– was investigated in aqueous solutions as a function of the pH and c(Fe3+) : c(HL) molar ratio. Stability constants of the complexes [FeL(H2O)4]2+, [FeL(H2 O)3(OH)]+, [FeL2 (H2O)2]+, [FeL2(H2O)(OH)] and [FeL2(OH)2]– were determined by the evaluation of UV-VIS spectral data. Based on the stability constants, distribution of the above complexes, [Fe(H2O)6]3+, and [Fe(H2O)5(OH)]2+ in solutions of various composition were calculated. The paper indicates a compatibility of the used data treatment and that not taking hydroxo complexes into account. Properties of the investigated bromokojic acid and its iron(III) complexes are compared to those required for therapeutic application as alternative iron chelators.

4

Differential Pulse Polarographic Study of Mercury Complexes with Some Substituted Pyrimidines in Binary Acetonitrile-Dimethylformamide Mixtures

Maddah B., Alizadeh K., Shamsipur M., Moghimi A., Ganjali M.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 5

737-744

EN

The complex formation of Hg2+ ion with five synthesized substituted pyrimidines in binary acetonitrile-dimethylformamide (AN-DMF) mixtures was studied by differential pulse polarography at 25 graduate C. The stoichiometry and stability of the complexeswere determined by monitoring the shift in the Hg2+ differential pulse peak potential against the pyrimidines concentration. In all cases studied, itwas found that the stability of the resulting 1:1 complex decreases drastically by increasing the amount of dimethylformamide in the binary mixtures. The observed stability order in a given solvent mixture is discussed in terms of the solvating ability of the solvent, donor site number, and steric hindrance on the pyrimidines.

5

Complex Formation Equilibria and Potentials of Mn(III)/Mn(II) Couple in the Presence of 1,10-Phenanthroline Derivatives in Aqueous Solutions

Andrijewski G., Nowak L., Tomczyk D., Różański R., Dałkowski R.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 5

693-701

EN

Formation constants ofMn(II) complexes with 5-nitro-, 5-chloro-, 5-methyl-, 4-methyl-, 2,9-dimethyl-, 4,7-dimethyl- and 5,6-dimethyl-1,10-phenanthroline and formal potentials of Mn(III)/Mn(II) couple in the presence of these compounds by use of potentiometric method were determined and used to calculate formation constants of Mn(III) complexeswith these ligands.Anumerical method of manganese(III) complexes formation constants calculation from potentiometric and voltammetric data was proposed and tested for iron(III) complexes. The influence of substituents on protonation and stability constant values was analyzed taking into account suitability of the ligand to stabilize thermodynamically unstableMn(III) ion and protect it from disproportionation.

6

Determination of Stability Constans of Copper(II)/Cobalt(II)-Methionine and Copper(II)/Cobalt(II)-Methionine-Cysteine (Binary and Mixed) Complexes by Paper Electrophoretic Technique

Tewari B.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 12

1853-1860

EN

The stability constants of copper(II) and cobalt(II) with methionine and cysteinewere determined by paper ionophoretic technique. Beside binary, mixed ligand complexes have also been studied, in which methionine and cysteine act as primary and secondary ligand, respectively. The stability constant of Cu(II)-methionine-cysteine and Co(II)-methionine-cysteine mixed ligand complexes were found to be 2.80+ -0.07 and 2.44+ -0.11 (logarithm of stability constant values), respectively at ionic strength 0.1 M and temperature of 35 graduate C.

7

Competitive Potentiometric study of a Series of 18-Crown-6 with Pb2+, Ag+, and Tl+ Ions in Methanol Using Ag+/Ag Electrode

Zolgarnein J., Azimi G., Habibi M.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 6

795-802

EN

The complexation of Ag+, Tl+ and Pb2+ with 18-crown-6 (18C6), dibenzo-18-crown-6 (DB18C6), dicyclohexyl-18-crown-6 (DCY18C6), and dibenzopyridino-18-crown-6 (DBPY18C6) in methanol solution have been studied by a competitive potentiometry, using Ag+/Ag electrode as a sensor. The stoichiometry and stability constants of resulting complexes have been evaluated by MINIQUAD program. The stoichiometry for all resulting complexes was 1:1. The order of stability of Ag+ complexes with used crown ethers varied as DBPY18C6 > DCY18C6 > 18C6 > DB18C6. For Pb2+, and Tl+ , the sequence of stability of complexes with each of these crown ethers (except of DBPY18C6) varied in the order Pb2+>Ag+>Tl+ . The major trend of stability of resulting complexes of these macrocycle with Pb2+ and Tl+ varied in the order DCY18C6 > 18C6 > DBPY18C6 > DB18C6 with few exceptions.

8

Application of Isotachophoresis for Determination of Anionic Forms of Phosphonic Acids

Górecki H., Szczygieł B, Drela I.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 9

1691-1702

EN

Using a capillary electrophoresis analyser, the concentrations of anionic forms of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) and N-trismethylenephosphonic acid (NTMP) were determined by the isotachophoresis method. The measurements were performed at pH = 4.2, 6.0 and 8.0. In each case the proper leading/terminating electrolyte system was selected on the basis of literature and authors'own research. The results of isotachophoretic analyses were found to be in good agreement with the results derived from dissociation constants determined by potentiometric method. Considerable difficulties were encountered in interpretation of the results obtained for pH = 8.0 since individual steps in the isotachopherograms were fuzzy and distorted probably due to incomplete separation of the analysed sample into zones. Knowledge of the kind and concentration of ligand forms of chelating compounds, to which PBTC and NTMP belong, can be useful for reclamation of soils polluted with heavy metals.

9

Fluorometric Determination of Stability Constants of Inclusion Complexes of Naproxen and Charged Cyclodextrins in Aqueous Solutions. Nonlinear vs Linear Data Processing

Sadlej-Sosnowska N., Gasiński Ł., Ozimiński W. P.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 8

1039-1048

EN

Stability constants of complexes of naproxen with monoamino-_-cyclodextrin and carboxymethyl-_-cyclodextrin in both acidic and basic solution have been determined by fluorometry and compared with those of parent _-cyclodextrin. It appeared that a charged group linked to the cyclodextrin rim decreased its complexing ability. For determination of the stability constants, nonlinear fitting has been used as well as three methods, which consist in linearization of the original hyperbolic equation. These methods of data processing have been compared.

10

Equilibrium StudyofIminodi(methylenephosphonic) Acid Complexeswith Some Metal Ions

Kurzak B., Kamecka A.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 9

1059-1077

EN

This article discusses coordination preferences of N-substituted iminodi(methylenephosphonic) acids to the different metal ions in an aqueous solution. These ligands exhibit high complexation efficiency towards divalent metal ions. This results from both dinegatively charged phosphonate groups as well as the imino nitrogen present in their structure. A significant preference for an equimolar stoichiometry has been demonstrated in these systems. The only exception is the N-2-methyltetrahydrofuryliminodi( methylenephosphonic) acid with a tetrahydrofuryl moiety, placed in the sterically favoured position that allows its oxygen atom to be an effective metal binding site. Specific interactions between metal ions and furyl oxygen results in higher binding ability of this ligand and a formation of 1:2 species. Coordination properties of iminodi- (methylenephosphonic) acids are important factors to understand the role of the ligands and metal ions in biological systems. A summary presented in this review points on the direction of the research for future work in this area, which should be developed.

11

Competitive Spectrophotometrc Study of Complexation of Dibenzopyridino-18-crown-6 with Ca2+, Sr2+, and Ba2+ in Binary Dimethylsulphoxide-Acetonitrile Solutions

Zolgharnein J., Zahirredini F., Azimi G.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 7

813-820

EN

The complexation of dibenzopyridino-18-crown-6 (DBPY18C6) with Ca2+, Sr2+ and Ba2+ has been studied in binary dimethylsulphoxide - acetonitrile mixtures at 25_C by a competitive spectrophotometric technique, using murexide as a metal ion indicator. Stoichiometry and stability of the resulting complexes were evaluated by KINFIT program. The stability of 1:1 complexes prepared were found strongly solvent dependent. There is an inverse linear relationship between log Kf and mole fraction of dimethylsulphoxide (DMSO) in the solvent. In all these solvents the increase of %AN increases the stability of DBPY18C6 complexes with alkaline earth cations in the sequence Ba2+ > Sr2+ > Ca2+.

12

Determination of Stability Constants of Complexes of Selected Amide Ionophores with Alkali Metal Cations

Bocheńska M., Korczagin I.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 4

601-606

EN

Properties of four amide-type ionophores towards binding of alkali metal cations (K+, Na+, Li+) have been established by determining the respective complex stability constants with the use of the liquid membrane ion-selective electrodes (ISEs).

13

The Influence of Structural Effects on the Complexing Ability of Crown Ethers III. Rubidium Complexes Formed by the Ligands of the 18C6 Typ

Filipek S., Krzyśko K., Kalinowski M. K.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 12

1887-1893

EN

A combined AM 1 and molecular mechanics study of the complexation of the rubidium cation by nine substituted crown ethers, L, containing 18 atoms of macroring is presented. The role of microsolvation was incorporated into the models by studying the complexes surrounded by six methanol molecules. The substituent effect is related to the interaction energy, Eint, which was computed for the clusters LRb+(CH3OH)6 in their lowest energy conformations. This is demonstrated by the linear correlation found by plotting logKs vs. Eint, where Ks stands for stability constant of a complex. The appropriate Ks values were calculated on the basis of cyclic voltammetric measurements.

14

Study of the Stability of Some Ion-Pairs in Non-Aqueous Solutions by Potentiometric and Spectrophotometric Methods

Gorodkiewicz E., Figaszewski Z.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 1

127-133

EN

Changes in selected complexes caused by photodissociation were studied potentiometrically by measuring the time dependence of electromotive force of suitable cells and spectrophotometrically by measuring the time dependence of absorbance to evaluate the stability constants. Ion pairs labetalol (LAB)-reineckate (REINE) in nitromethane and crystal violet (CV)-tetrachloroferrate(III) (FeCl4) in tetrachloroethane were used. The concentration ranges were determined, in which the EMF variations are greatest: the 4-5.5 × 10-4 mol l-1 range for the LAB-REINE complex and the 0.9-3 × 10-6 for the CV-FeCl4 complex. Linear dependence of the EMF variation on the intensity of radiation, as well as a slight effect of temperature on irradiated solution were found. The stability constants of the studied complexes in chloroform, determined directly from spectrophotometric measurements are log Beta av = 6.6 for LAB-REINE complex and log av = 7.3 for the CV-FeCl4 complex.

15

Metal Complexes of C-Functionalized Macrocyclic Dioxotetraamines Bearing 8-Hydroxyquinoline Stability in Aqueous Solutions

Su X., Zhu S. -R., Sun W., Zhao G. -H., Chen Y. -T.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 5

623--632

EN

Two novel 8-hydroxyquinoline connected dioxotetraamines have been designed and synthesized, and have been characterized by elemental analysis, IR, mass spectra and 1H NMR. The two ligands L1 and L2 have two chelating groups. Each can react with a transition metal ion forming complexes. Potentiometric titrations have been performed in 0.1 mol/L NaNO3 at 25_C giving the 1:1 stability constants. Coupled with UV spectroscopy the affinity of 8-hydroxyquinoline and dioxotetraamines to transition metal ions were compared and the possible structure of the metal complex species in solution was discussed. The results show that as to Mn2+, Zn2+ and Co2+, 8-hydroxyquinoline is a stronger chelating reagent than dioxo[13] or [14]tetraamine macrocycles and at 1:1 molar ratio (M:L), the former binds in 100% to the metal ions, while the dioxotetraamines can be only partially or not coordinated.

16

The role of the side group in reactions involving 1-propyl-2-methylimidazole and 1-propyl-2-imidazole-carboxaldehyde and Co(II), Ni(II), Cu(II) and Zn(II) ions

Barszcz B., Kulig J., Jezierska J., Lisowski J.

Polish Journal of Chemistry

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1999

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vol. 73 nr 3

447-456

EN

The complexing properties of 1-propyl-2-methylimidazole (1-Pr-2-CH3Im) and 1-propyl-2-imidazolecarboxaldehyde (1-Pr-2-CHOIm) with CoII, NiII, CuII and ZnII were investigated pH-metrically at 25oC and at the ionic strength of 0.5 mol dm-3(KNO3). The stability constans calculated indicate the formation of complexes with metal: ligand ratio of 1:1, 1:2, 1:3, and 1:4. The stability of the metal complexes with both imidazoles depends mostly on the substituent situated between the nitrogen atoms of the imidazole ring. It was found that the carboxalaldehyde oxygen atom participates in the formation of the coordination bond. The formation of the weak chelate copper (II)-1-propyl-2-imidazolecarboxaldehyde complexes was confirmed by EPR spectra. The electronic spectra reveal that the cobalt(II) forms both tetrahedral and octahedral species with 1-Pr-2-CH3Im, but 1_Pr-2-CHIIm forms only six-coordinated compounds. The NMR spectra of 1_Pr-2-CHOIm indicate that hydration of the CHO takes place when Zn(II) ions are introduced into the ligand solution at pH5.03.

17

Oxovanadium(IV) complexes of 1-hydroxyalkane-1,1-diyldiphosphonic acids

Dyba M., Kozłowski H., Tlałka A., Leroux Y., El Manouni D.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 7

1148-1153

EN

Potentiometric and spectroscopic (EPR and UV-VIS) methods were used to study the oxovanadium(IV) complexation with several 1-hydroxyalkane-1,1-diyldiphosphonic acids. Coordination of oxovanadium(IV) to all diphosphonic ligands studied starts at very low pH and formation of the stable monomeric and trinuclear species between pH range 2-9 is observed.

18

Interaction of sodium and potassium ions with the cis isomers of dicyclohexyl-18-crown-6 in nonaqueous media

Wagner-Czauderna E., Filipek S., Kalinowski M.K.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 10

2294-2302

EN

The formation constants, K-s for 1:1 complexes of the cis-syn-cis and cis-anti-cis isomers of dicyclohexyl-18-crown-6 with sodium and potassium cations have been electrochemically determined in 10 nonaqueous (protic and aprotic) media. Linear correlations were obtained for log K-s with standard Gibbs transfer energies of the cation from water to a given solvent. The cis-anti-cis isomer was found to be a weaker complexer than the cis-syn-cis one and this was elucidated in terms of the ligand solvation. Energy-minimized structures of the ligands and complexes suuuounded by methanol and acetonitrile molecules were established by molecular dynamics computations.

19

Fixation by H-bonding of ligands in polymer coils

Huyskens P., Nelis K., Vael Ch., Verstraeten K., Zeegers-Huyskens Th.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

251-262

EN

The stability constants of H-bonds between phenols and the ester groups of polyethylmethacrylate (PEMA) in CCl4 determined by IR measurements, are of the same order of magnitude as those of the phenols with the low-molecular model substance ethylisobutyrate. In absence of additives, the cloud points at 25 degree C of PEMA (Mw=258000) in CCl4-n-hexane mixtures are fairly well predicted by the equations of Huyskens et al. The presence of phenols displaces these cloud points towards higher values of the relative mole fraction of the cosolvent. This is also the case when acetone is used as additive. Beyond the cloud point, viscosity measurements show that practically no polymer coils remain in the supernatant liquid. However, after the phase separation, the additives behave in a completely different way. Dipolar measurements show indeed that the concentration of acetone in the supernatant liquid is of the same order as in the solution before the precipitation, whereas the phenol molecules are predominantly found in the precipitated flakes. This illustrates the fundamental difference between non-specific dipole-dipole interactions and specific intermolecular forces like H-bonds, whose characteristics were extensively studied during more than thirty years by Lucjan Sobczyk and his coworkers.