Authors:Zuzana Bujdošová, Katarína Győryová, Dagmar Mudroňová, Daniela Hudecová, and Jana Kovářová
New zinc(II) 4- and 5-chlorosalicylate complexes of general formula [Zn(X-sal)2(L)n(H2O)x] (where X-sal = 4-Clsalicylate, 5-Clsalicylate; L = N,N-diethylnicotinamide, isonicotinamide, theophylline; n = 1, 2; x = 0, 1, 2, 4) were prepared. The complexes were determined by elemental analysis and characterised by infrared spectroscopy. The thermal behaviour of the complexes was studied by simultaneous TG, DTG and DTA methods under dynamic air conditions. The thermal decomposition is a multi-step process. In the first step of the thermal decomposition, water is released in hydrated compounds. The anhydrous compounds start to decompose by the release of organic ligand, followed by chlorosalicylic acid, chlorophenol and carbon monoxide. The final solid product of the thermal decomposition is zinc oxide. The volatile products of the thermal decomposition were determined by mass spectrometry. The antimicrobial activities of the complexes were evaluated against selected pathogen and probiotic bacteria, yeasts and fungi strains. Bioactivities of the tested compounds are different against bacteria, yeasts and filamentous fungi. It was found that bacteria were more sensitive to the studied zinc(II) complex compounds than yeasts or filamentous fungi.
Authors:J. Skoršepa, Katarína Györyová, and M. Melník
Zinc carboxylates complexed with N-donor ligands have potential antifungal effects. The preparation, identification and especially
the thermal properties of four hitherto non-characterized compounds of this group of general formula (CH3CH2COO)2Zn·2L·H2O are described in this paper. The experimental results are confronted with present knowledge on analogous compounds.
Authors:Anna Kropidłowska, M. Strankowski, Maria Gazda, and Barbara Becker
The thermal behavior of Mn(II) silanethiolate series [Mn(SR)2L(MeOH)n],
where R=SSi(OBut)3, L=heterocyclic nitrogen base and n=0,
1 or 2 has been comparatively investigated using differential scanning calorimetry
(DSC), thermogravimetry (TG) and TG-infrared spectoscopy (IR) techniques.
The TG curves indicate the differences in the thermal decomposition due to
presence of distinct N-donor ligands and labile MeOH molecules coordinated
to the central atom. The first step on the TG curves (60–110C)
corresponds to the elimination of alcohol from respective complexes. The main
step (150–350C) can be assigned to the decomposition of the complexes
yielding Mn3O4 and silica as
the main final products, identified by X-ray diffraction patterns.
Authors:K. Györyová, J. Kovářová, E. Andogová, V. Zeleňák, and F. Nour El-Dien
Zinc carboxylate complexes with N-donor ligands exhibit antimicrobial and antifungal effects. The preparation and thermal properties of complex compounds Zn(isobut)2 and Zn(isobut)2L(isobut=(CH3)2CHCOO–, L=papaverine — pap, phenazone — phen) are described in this paper. The newly synthesized compounds were characterized by elemental analysis, IR spectroscopy and TG/DTG, DTA methods.During the thermal treatment it was found that the release of organicligands (pap, phen) was followed by pyrolysis of zinc(II) isobutyrate. (C3H7)2CO and CO2 were found as gaseous products and zinc oxide as the final product of thermal decomposition. Gaseous and solid products of thermal decomposition were confirmed by chemical analysis, IR spectra and X-ray powder diffraction.
Authors:Erika Szunyogová, Dagmar Mudroňová, Katarína Györyová, Radomíra Nemcová, Jana Kovářová, and Lenka Piknová-Findoráková
Spectroscopic (IR), thermoanalytical (TG/DTG, DTA) and biological methods
were applied to investigate physicochemical and biological properties of seven
zinc(II) complex compounds of the following formula Zn(HCOO)2·2H2O
(I), Zn(HCOO)2·tph (II), Zn(CH3COO)2·2H2O (III), Zn(CH3COO)2·tph
(VI), Zn(CH3CH2CH2COO)2·2H2O (VII), where tph=theophylline, phen=phenazone. The formation of various
intermediates during thermal decomposition suggests the dependence on the
length of aliphatic carboxylic chain and type of N-donor ligand (tph, phen).
The final product of the thermal decomposition was ZnO. The antimicrobial
activity of these complexes were tested against G+
and G– bacteria. Strong inhibitive effect
was observed towards E. coli, salmonellae
and Staph. aureus.
Authors:E. Jóna, L’. Lajdová, L’. Kvasnicová, S. Lendvayová, M. Pajtášová, D. Ondrušová, P. Lizák, and S. C. Mojumdar
quinoline derivates to improve the understanding of drug-metal ion interactions. This study is a continuation of previous studies on the stereochemistry [ 3 ] and thermal properties [ 4 – 11 ] of Mg(II) complexes with N-donorligands. This article deals with
Authors:S. Materazzi, S. Vecchio, L. W. Wo, and Curtis S. De Angelis
economically and ecologically relevant. The use of catalytically active transition metal complexes, which can activate hydrogen peroxide, might be a means of achieving these aims.
Several manganese complexes with polydentate N-donorligands have been
Authors:V. Logvinenko, T. Mitkina, V. Drebushchak, and V. Fedin
Logvinenko , V , Dybtsev , D , Fedin , V , Drebushchak , V , Yutkin , M . The stability of inclusion compounds under heating. Part 2. Inclusion compounds of layered zinc camphorate, linked by linear N-donor