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Tiosemikarbazony : właściwości koordynacyjne w aspekcie aktywności biologicznej

Ostrowska M., Toporivska Y., Pyrkosz-Bulska M., Gumienna-Kontecka E.

Wiadomości Chemiczne

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2018

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[Z] 72, 7-8

449--467

EN

Thiosemicarbazones are considered to be potential therapeutics, because they possess a broad range of biological properties including antitumor, antimalarial and antimicrobial activity. Generally, the tiosemicarbazones coordinate to the metal centre by means of an (N,S) bidentate mode, and when an additional coordinating group is present, more diversified binding modes can occur such as a tridentate (X,N,S) coordination fashion. The stability of the metal complexes formed with the tiosemicarbazoness strongly depends on the character of the metal ion, the X-donor atom of the additional functional group and the position and type of the substituents at the tiosemicarbazones. The most prominent representative of this family is the α(N)-heterocyclic Triapine (3-aminopyridine- 2-carbaldehyde thiosemicarbazone; 3-AP), which is currently undergoing different phase-I and -II clinical trials as an antitumor agent, and demonstrates promising activity. Triapine is a very strong inhibitor of ribonucleotide reductase, the rate determining enzyme in the supply of deoxyribonucleotides for DNA synthesis required for cell proliferation. The mechanism of action involves most probably the formation of an iron(II)–Triapine complex, which reacts with molecular oxygen to result in the generation of reactive oxygen species. Subsequently, these reactive oxygen species are responsible for the quenching of the active-site tyrosyl radical of ribonucleotide reductase required for the enzymatic activity. As a result, the coordination chemistry of iron complexes of tiosemicarbazones has been receiving considerable attention. This review describes the coordination chemistry of tiosemicarbazones, in particular analogs of Triapine. The coordination compounds of d-block elements are discussed with respect to their bonding and structures. Several of complexes are mononuclear, with distorted tetrahedral, square planar, square pyramid or octahedral as their common geometries. The metal-binding ability of STSC at physiological pH was compared and shown. Further, various biological applications with emphasis an anticancer activity of the ligands/complexes are discussed in brief so as to indicate the importance of ligands under consideration.

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Biological screening and assessment of certain substituted monoazo heterocycles containing sulphur and / or nitrogen and their seleno like moieties

Khalifa M. E., Gobouri A. A.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 4

28--35

EN

The monoazo substituted five membered heterocycles, along with their seleno like moieties are still of interest in organic chemistry due to their medicinal and valuable applications. In continuation of our interest in the study of heterocyclic azo compounds containing sulphur and / or nitrogen heteroatoms, the synthesis of 5-aryl mono azo-thiazol-2-ylcarbamoyl-thiophene along with their seleno like derivatives of pyridine, pyridazine and quinolone, were accomplished. All the synthesized compounds were in vitro screening of their antioxidant activity, antitumor activity against Ehrlich ascites carcinoma cell EACC cell line and antimicrobial activity against various pathogenic microorganisms, such as Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Salmonella typhimurium) and fungi strains of Aspergillus flavus and Candida albicans. The structural–activity relationship was studied based on the obtained data.

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Drożdże piekarnicze Saccharomyces cerevisiae jako eukariotyczny organizm modelowy - cz. II

Cal-Bąkowska M.

Laboratorium - Przegląd Ogólnopolski

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2015

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nr 9-10

65--68

PL

Odpowiedź komórkowa na uszkodzenia DNA jest niezwykle podobna pomiędzy komórkami drożdży oraz wyższymi eukariontami. Drożdże Saccharomyces cerevisiae są użytecznym modelem w badaniach wielu molekularnych mechanizmów, w tym działania nowych chemioterapeutyków. Na modelu drożdżowym możliwe jest prowadzenie bardzo szczegółowych i ciekawych badań nad cyklem komórkowym.

EN

The cellular response to DNA damage is remarkably similar between the yeast cells and higher eukaryotes. The yeast Saccharomyces cerevisiae is a useful model to study many molecular mechanisms and also the mechanism of action of new chemotherapeutic agents. It is possible to carry out on yeast model detailed and interesting research of the cell cycle.

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Synthesis of 23-Oxa-22-deoxo Analogues of OSW-1 Aglycone

Kruszewska A., Wilczewska A., Wojtkiewicz A., Morzycki J.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 4

611-615

EN

Four ether analogues of OSW-1 aglycone were obtained by alkylation of a steroid alcohol with alkyl bromide. During theWilliamson reaction promoted by sodium hydride in addition to alkylation, an unusual dehydrogenation of secondary alcohol was observed.

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1H, 13C, and 15N NMR Study of Nitrosoureido Sugars, Derivatives of 2-Amino-2-deoxy-beta=D-glucopyranoside and Amino Acids or Peptides

Wawer I., Weychert M., Piekarska-Bartoszewicz B., Temeriusz A.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 8

1127-1136

EN

Nitrosoureido sugars with amino acid and dipeptide ester residue were characterized by 1H, 13C and 15N NMR and their spectra were assigned using 1D and 2D NMR methods. The N-nitrosation of ureido sugars frequently yields a mixture of isomers. In the case of ureido sugars with amino acid residues preferably the N3-NO isomers were obtained, whereas for compounds with dipeptide esters the N1-NO isomers dominate. The results are in agreement with the molecular modelling (PM3) predictions, when the intramolecular hydrogen bonds, net charges at nitrogen atoms and heat of formations of particular isomers are considered.