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Denisa Tarabová, Viktor Milata and Jiří Hanusek

Abstract

A set of 22 anilinomethylidene derivatives (13 new ones) of di(m)ethyl malonate, malononitrile and pentane-2,4-dione with various substituents in position 4- and 3-, respectively were prepared to study the characteristic influence of these substituents and solvents on chemical shifts in 13C NMR spectra and like reference compounds for kinetic measurements.

Open access

Viktor Milata, Ladislav Reinprecht and Juraj Kizlink

Synthesis and antifungal efficacy of 1,3,5-triazines

1,3,5-triazines with tree identical groups: benzotriazol-1/2-yl, imidazol-1-yl, pyrazolyl-1-yl, 3,5-dimethylpyrazolyl-1-yl, 4,5-diphenylimidazol-1-yl, benzimidazolyl-1-yl, 2-methylbenzimidazolyl-1-yl, or 2-phenylbenzimidazolyl-1-yl were synthesised. Their biological activity against wood-destroying fungi Serpula lacrymans, Coniophora puteana and Trametes versicolor was tested by the impregnated filter paper method. S. lacrymans occurred as the most sensitive fungus (from the 3 fungi) in the presence of triazines. Triazines having three imidazol or three 4,5-diphenylimidazol groups were a slightly more effective than others. However, their efficacy in comparison with the commercial fungicides Tebuconazole and IPBC was insufficient.

Open access

Denisa Tarabová and Viktor Milata

Abstract

There were studied series of activated enolethers (alkoxymethylene derivatives of malonic or 3-oxobutanoic acids derivatives of general formula R-O-CH=C(R1, R2) where R1 = R2/ R1 ≠ R2 (R1, R2 = CO2CH3, CO2CH2CH3, COCH3, CN) with N,N-dimethylhydrazine. They smoothly provided products of nucleophilic vinylic substitution reaction - dimethyl hydrazinyl methylene derivatives of malonic or 3-oxobutanoic acids (enhydrazines), respectively from 20 minutes to 2 hours at room temperature.

Open access

Soňa Jantová, Dominika Topoľská, Michaela Janošková, Miroslav Pánik and Viktor Milata

Abstract

The new synthetically prepared quinolone derivative 7-ethyl 9-ethyl-6-oxo-6,9-dihydro[1,2,5]selenadiazolo [3,4-h]quinoline-7-carboxylate (E2h) showed in our previous study cytotoxic effects towards tumor cells and immunomodulatory activities on RAW 264.7 cell line murine macrophages. E2h may have a potential use as a novel chemotherapeutic agent with immunomodulatory properties and the ability to induce apoptotic death of cancer cells. The aim of the present study was to examine the antiproliferative/cytotoxic activities of E2h on human non-cancer fibroblast BHNF-1 cells and reconstructed human epidermis EpiDerm™. Further the effects of E2h on tissue structure and morphology were examined. Cytotoxic/toxic studies showed that selenadiazoloquinolone is not toxic on normal human fibroblast cells BHNF-1 and dimensional skin constructs EpiDerm™. Evaluation of morphological changes in EpiDerm™ showed no change in the construction and morphology of skin tissue treated by E2h compared to control.

Open access

Anton Gatial, Viktor Milata, Nadežda Prónayová, Klaus Herzog and Reiner Salzer

Abstract

The IR (4000-400 cm-1) and Raman (4000-50 cm-1) spectra of 3-methoxymethylene-2,4-pentanedione [H3C-O-CH=C(COCH3)2] as a liquid and solutes in various solvents of different polarity have been recorded at ambient temperature. Additional IR and Raman spectra were obtained for amorphous and crystalline solid state at low temperature. The vibrational spectra revealed that the compound exists at least in two dominant conformers of different polarity and that the conformer present in the solid phase is less polar. NMR spectra in various solvents at different temperatures were also obtained.

The compound can exist in several conformers due to the rotation around O-C= and both =C-C bonds with planar or nonplanar arrangements of heavy atoms. Ab initio MP2 and DFT calculations using a wide scale of basis sets were carried out. According to these calculations six conformational structures of the eight theoretically possible conformational structures with the methoxy group oriented as anti or syn and carbonyl groups oriented as Z or E towards the C=C double bond were obtained at potential energy surface. It has been shown that the conformers with the E orientations of both acetyl groups are not the stable ones. The calculated ab initio MP2 and DFT energies of all found conformers in vacuum suggest the most stable ZEa conformer where Z and E regard to the trans and cis acetyl groups, respectively and a denotes the orientation of the methoxy group. The EZa conformer was calculated as the second most stable one with the energy by at least 10 kJ mol-1 higher. Corrections of the relative energies of single conformers obtained in vacuum on the polar surroundings were done by including the solvent effect into the calculations using IEF Polarizable Continuum Model.

Assignments of the vibrational spectra for the studied compound were made with the aid of normal coordinate calculations employing scaled ab initio force field. The scaled ab initio frequencies as well as calculated energies indicate that ZEa is the conformer present in the solid phase.