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A series of thiosemicarbazone derivatives was prepared and their anti-tumor activity in vitro was tested. The X-ray investigation performed for compounds T2, T3 and T5 confirmed the synthesis pathway and assumed molecular structures of analyzed thiosemicarbazones. The conformational preferences of the thiosemicarbazone system were characterized using theoretical calculations by AM1 method. Selected compounds were converted into complexes of Cu (II) ions. The effect of complexing on anti-tumor activity has been investigated. The copper(II) complexes, with Schiff bases T1, T10, T12, T13, and T16 have been synthesized and characterized by chemical and elemental analysis, FTIR spectroscopy and TGA method. Thermal properties of coordination compounds were studied using TG-DTG techniques under dry air atmosphere. G361, A375, and SK-MEL-28 human melanoma cells and BJ human normal fibroblast cells were treated with tested compounds and their cytotoxicity was evaluated with MTT test. The compounds with the most promising anti-tumour activity were then selected and their cytotoxicity was verified with cell cycle analysis and apoptosis/necrosis detection. Additionally, DNA damages in the form of a basic sites presence and the expression of oxidative stress and DNA damage response genes were evaluated. The obtained results indicate that complexation of thiosemicarbazone derivatives with Cu (II) ions improves their antitumor activity against melanoma cells. The observed cytotoxic effect is associated with DNA damage and G2/M phase of cell cycle arrest as well as disorders of the antioxidant enzymes expression.

The crystal structure determination of oxazoline-1,2,4-triazine ligand

A series of thiosemicarbazide derivatives was designed and synthesized by reaction of carboxylic acid hydrazide with isothiocyanates. The molecular structures of the investigated thiosemicarbazides were confirmed and characterized by spectroscopic analysis. The conformational preference of carbonylthiosemicarbazide chain and intra- and intermolecular interactions in the crystalline state were characterized using X-ray analysis. The antituberculosis activity of the target compounds were tested in vitro against four Mycobacterium strains: M. H37Ra, M. phlei, M. smegmatis, M. timereck. The most active compounds were those with 2-pyridine ring. They exhibited lower minimal inhibitory concentration (MIC) values in the range 7.81–31.25 μg/mL in comparison to the other isomers. Compound 5 had activity against M. smegmatis at a concentration of 7.81 μg/mL whereas compound 2 had activity against all tested strains at a concentration of 15.625 μg/mL. The molecular docking studies were performed for investigated compounds using the Mycobacterium tuberculosis glutamine synthetase MtGS as their molecular target.

Six novel imidazoline derivatives were synthesized and tested in antifungal assays. One of the compounds, N-cyclohexyl-2-imino-3-(4-nitrophenyl)imidazolidine-1-carboxamide showed moderate activity against several clinical strains of Candida albicans. Its structure was solved by X-ray crystallography and its mode of action was deduced using molecular modelling. It was found to be similar to that of fluconazole. The potential for further optimization including SAR of the compound is briefly discussed.