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The methoxy analogue of a trans -stilbene compound - 2,3,3',4'-tetramethoxy- trans -stilbene - was selected to characterize its crystallographic structure, intermolecular interactions and molecular dynamics. The sample was studied using single-crystal X-ray diffraction (XRD), infrared spectroscopy (FT-IR), liquid and solid-state 1 H and 13 C nuclear magnetic resonance (NMR) and quasielastic neutron scattering (QENS). The compound crystallized in the orthorhombic Pbca space group. The experimental methods were supported by theoretical calculations, density functional theory (plane-wave DFT) and molecular dynamics simulations (MD) methods. Combining several experimental and simulation techniques allowed the detailed analysis of molecular reorientations and provided a consistent picture of the molecular dynamics. The internal molecular mobility of the studied compound can be associated with the reorientational dynamics of four methyl groups. Interestingly, a large diversity of the energy barriers was observed - one methyl group reoriented across low activation barriers (∼3 kJ mol -1 ), while three methyl groups exhibited a high activation energy (10-14 kJ mol -1 ) and they are characterised by very different correlation times differing by almost two orders of magnitude at room temperature. The intramolecular interactions mainly influence the activation barriers.

Newly developed tetra- and octasubstituted methimazole-phthalocyanine conjugates as potential photosensitizers have been obtained. Synthesized intermediates and final products were characterized by the MALD-TOF technique and various NMR techniques, including 2D methods. Single-crystal X-ray diffraction was used to determine the crystal structures of dinitriles. The studied phthalocyanines revealed two typical absorption bands-the Soret band and the Q band. The most intense fluorescence was observed for octasubstituted magnesium(II) phthalocyanine in DMF (Φ FL = 0.022). The best singlet oxygen generators were octasubstituted magnesium(II) and zinc(II) phthalocyanines (Φ ∆ 0.56 and 0.81, respectively). The studied compounds presented quantum yields of photodegradation at the level between 10 -5 and 10 -6 . Due to their low solubility in a water environment, the liposomal formulations were prepared. Within the studied group, octasubstituted zinc(II) phthalocyanine at the concentration of 100 µM activated with red light showed the highest antibacterial activity against S. aureus equal to a 5.68 log reduction of bacterial growth.

Despite the continuous development of medicine, there is still a lack of effective and fully safe protocols for the treatment of neoplastic diseases. The drug-drug conjugates approach seems to give a chance to obtain more efficient molecules. New alkoxy and metronidazole substituted porphyrins were synthesized. Novel porphyrins were purified by flash column chromatography and characterized using NMR, MS, UV-Vis and HPLC. The Nuclear Magnetic Resonance study was performed to annotate experimentally observed 1 H NMR and 13 C NMR signals of new compounds. The 2D NMR techniques such as 1 H- 1 H COSY (Correlation Spectroscopy), 1 H- 13 C HSQC (Heteronuclear Single Quantum Correlation) and 1H-13C HMBC (Heteronuclear Multiple Bond Correlation) were used for the structure elucidation of the new compounds. In the range of 250-450 nm of the absorption spectra, the Soret band was observed, whereas the Q band was noted in the range of 500-650 nm. Compounds revealed a fluorescence quantum yield in the range 0.03-0.12. Singlet oxygen generation quantum yields up to 0.54 were determined. Electrochemical properties has also been studied. It has been noticed electropolymerization of compound bearing 5-nitroimidazole substituents. The photodynamic activity of the studied porphyrins against A549 and HEK001/HPV16 cancer cells were examined. The most active against A549 and HEK 001/HPV16 was light-excited trioxanonylporphyrin with the values of IC 50 equal to 0.49 μM and 50 nM respectively., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In screening studies, the cytotoxic activity of four metabolites of resveratrol analogue 3,4,5,4'-tetramethoxystilbene (DMU-212) against A-2780 and SKOV-3 ovarian cancer cells was investigated. The most active metabolite, 3'-hydroxy-3,4,5,4'-tetramethoxystilbene (DMU-214), was chosen for further studies. The cytotoxicity of DMU-214 was shown to be higher than that of the parent compound, DMU-212, in both cell lines tested. Since DMU-212 was supposed to undergo metabolic activation through its conversion to DMU-214, an attempt was made to elucidate the mechanism of its anti-proliferative activity. We found that in SKOV-3 cells lacking p53, DMU-214 induced receptor-mediated apoptosis. In A-2780 cell line with expression of wild-type p53, DMU-214 modulated the expression pattern of p53-target genes driving intrinsic and extrinsic apoptosis pathways, as well as DNA repair and damage prevention. Regardless of the up-regulation of p48, p53R2, sestrins and Gaad45 genes involved in cancer cell DNA repair, we demonstrated the stronger anti-proliferative and pro-apoptotic effects of DMU-214 in A-2780 cells when compared to those in SKOV-3. Hence we verified DMU-214 activity in the xenograft model using SCID mice injected with A-2780 cells. The strong anti-proliferative activity of DMU-214 in the in vivo model allowed to suggest the tested compound as a potential therapeutic in ovarian cancer treatment.