Karolina Królewska

Design, Synthesis and Cytotoxicity of a New Series of Isoxazolidine Based Nucleoside Analogues

5‐Arylisoxazolidin‐3‐yl‐3‐diethoxyphosphonates have been synthesized from N‐methyl‐C‐diethoxyphosphorylnitrone and vinyl aryls in good yields and their transformation into the respective phosphonic acids has been accomplished via dealkylation procedure using trimethylsilyl bromide. Phosphonates having 1‐ and 2‐naphthyl substituents at C5 in the isoxazolidine ring as well as the respective phosphonic acids have been found cytotoxic to HeLa and K562 cells with IC50 in the 0.1–0.3 mM range. Preliminary studies on mechanism of action imply that intercalation to DNA is not responsible for their cytotoxic properties.

Design, synthesis and cytotoxicity of a new series of isoxazolidines derived from substituted chalcones

A new series of isomeric isoxazolidin-3-yl-3-phosphonates were synthesised from N-methyl-C-diethoxyphosphorylnitrone and substituted chalcones. The respective isoxazolidin-3-yl-3-phosphonic acids were obtained from phosphonates via dealkylation procedure using trimethylsilyl bromide. Selected phosphonates and their respective phosphonic acids were screened for their cytotoxic activity to HeLa and K562 cells with IC(50) in the 0.1-0.3mM range.

Chelating ability and biological activity of hesperetin Schiff base

Hydrazone hesperetin Schiff base (HHSB) - N-[(±)-[5,7-dihydroxy-2-(3-hydroxy-4-methoxy-phenyl)chroman-4-ylidene]amino]benzamide has been synthesized and its crystal structure was determined. This compound was used for the formation of Cu(II) complexes in solid state and in solution which were characterized using different spectroscopic methods. The analyses of potentiometric titration curves revealed that monomeric and dimeric complexes of Cu(II) are formed above pH7. The ESI-MS (electrospray ionization-mass spectrometry) spectra confirmed their formation. The EPR and UV-visible spectra evidenced the involvement of oxygen and nitrogen atoms in Cu(II) coordination. Hydrazone hesperetin Schiff base can show keto-enol tautomerism and coordinate Cu(II) in the keto (O(-), N, Oket) and in the enolate form (O(-), N, O(-)enol). The semi-empirical molecular orbital method PM6 and DFT (density functional theory) calculations have revealed that the more stable form of the dimeric complex is that one in which the ligand is present in the enol form. The CuHHSB complex has shown high efficiency in the cleavage of plasmid DNA in aqueous solution, indicating its potential as chemical nuclease. Studies on DNA interactions, antimicrobial and cytotoxic activities have been undertaken to gain more information on the biological significance of HHSB and copper(II)-HHSB chelate species.

Synthesis and biological activity of novel series of heterocyclic compounds containing succinimide moiety

Abstract In the search for biological agents, a series of new N-substituted ethyl 11-ethyl-7-methyl-3,5,10-trioxo-4-azatricyclo[5.2.2.02,6]undecane-8-carboxylates 3, 9-methyl-3,5,8-trioxo-4-azatricyclo[5.2.1.02,6]dec-1-yl acetates 6 and 1,3-dioxo-4,5,6,7-tetraphenyl-2,3,3a,4,5,7a-hexahydro-1H-isoindole-4-carboxylic acids 9 were prepared. All compounds were characterized by 1H NMR, ESI-MS, and elemental analyses. Moreover, for intermediate products 2, 5, and 8, X-ray structural analyses were conducted. Compounds 3a–e, 6a, 6b, 9a–e were tested for their cytotoxic properties in K562 and HeLa cells.

New, Substituted Derivatives of Dicarboximides and their Cytotoxic Properties.

A large group of aminoalkyl and aminoalkanol derivatives of selected dicarboximides were synthesized and characterized by 1HNMR, 13CNMR and ESI MS spectra analysis. The thirty nine new compounds were tested for their cytotoxic properties in human chronic (K562), acute leukemia (HL-60), and cervical cancer cells (HeLa) as well as in normal endothelial cells (HUVEC). The most promising compounds are 4-[2-(dimethylamino)ethyl]-, (diethylamino) ethyl]-, 4-[2-(piperidin-1-yl)ethyl]-, 4-[3-(dimethylamino)propyl]- and 4-[2-hydroxy-3-(propan- 2-ylamino)propyl]- derivatives of 1,7-diethyl-8,9-diphenyl-4-azatricyclo[5.2.1.0(2,6)]dec-8-ene-3,5,10-trione exhibiting high and selective cytotoxicity towards K562 and HL-60 cells (IC50 in the range of 1-10 µM) while being non-toxic towards HUVEC and HeLa cells (IC50> 100 μM). Moreover, the preliminary studies have showed that 4-[2-(piperidin-1-yl)ethyl]- 1,7-diethyl-8,9-diphenyl-4-azatricyclo [5.2.1.0(2,6)]dec-8-ene-3,5,10-trione induces programmed cell death (apoptosis) in leukemia cells.

Synthesis and preliminary studies of biological activity of amino derivatives of 4-azatricyclo- [5.2.1.02,6]dec-8-ene-3,5-dione with silicon in the structure

Abstract A series of 38 new derivatives of cyclic imides containing silicon in the structure was synthesized and characterized by 1H NMR, ESI-MS, and elemental analysis. Selected compounds (1l,m, 1g, 1o,p, 2l,m, and 2o,p) were tested for their cytotoxic properties in human chronic myelogenous leukemia (K562), human cervical cancer (HeLa), and normal endothelial cells (HUVEC). Seven compounds showed significant cytotoxicity. In addition, two compounds (1l and 2l) were tested toward affinity for 5-HT1A, 5-HT6, and 5-HT7 serotonin receptors, and all aryl/heteroarylopiperazino derivatives were tested for antimicrobial activity. The compounds tested toward affinity for selected serotonin receptors showed high and moderate affinity for 5-HT1A and 5-HT7, while the antimicrobial activity of tested compounds was not significant.

Synthesis and biological activity of 6-substituted 5-acetyl-4,7-dimethoxybenzofuran derivatives

Abstract In the search for new antimicrobial and anticancer agents, a series of (aryl/heteroaryl-piperazino-alkyl)-substituted derivatives of benzo[b]furans were prepared. All compounds were characterized by 1H NMR, 13C NMR, ESI-MS spectra and elemental analyses. Most of the investigated compounds had no antimicrobial activity (MIC > 512 mg/L) except for 2l, 2m and 2o, which showed activity against Candida albicans. None of the tested compounds showed significant anticancer activity in K562 and HeLa cells.