Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 6

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Acyclonucleosides: Acyclobenzimidazole nucleoside and nucleotide analogues and conformations of the acyclic chains by means of NMR spectroscopy

100%
Kazimierczuk Z., Stolarski R., Shugar D.
Acta Biochimica Polonica
|
1984
|
vol. 31
|
issue 1
33-48
2
Content available remote

7-Deazapurine 2'-deoxyribofuranosides are noncleavable competitive inhibitors of Escherichia coli purine nucleoside phosphorylase (PNP)

100%
Bzowska A., Kazimierczuk Z., Seela F.
Acta Biochimica Polonica
|
1998
|
vol. 45
|
issue 3
755-768
3
Content available remote

Synthesis and antimicrobial activity of new adamantane derivatives I.

100%
Orzeszko A., Gralewska R., Starościak B. J., Kazimierczuk Z.
|
2000
|
vol. 47
|
issue 1
87-94
EN
A series of fourteen derivatives of adamantane was synthesised. The new compound 4-(adamant-1-ylmethoxycarbonyl)phthalanhydride obtained from 1-adamantane- methanol and trimellitic anhydride chloride appeared very useful for preparation of a number of N-substituted phthalimides. Antimicrobial activity of the newly obtained derivatives such as, for example, 4-(adamant-1-ylmethoxycarbonyl)-N-(5-carboxypentamethylene)phthalimide or 4-(adamant-1-ylmethoxycarbonyl)-N-(L-alanyl)phthalimide was tested against Staphylococcus aureus, Bacillus sp., Micrococcus flavus and Enterococcus faecium. The minimal inhibitory concentration (MIC) for these compounds against S. aureus were 0.022 and 0.05 μg/ml, respectively.
4
Content available remote

5'-Esters of 2'-deoxyadenosine and 2-chloro-2'-deoxyadenosine with cell differentiation-provoking agents.

88%
Grieb P., Kryczka T., Wójtowicz R., Kawiak J., Kazimierczuk Z.
|
2002
|
vol. 49
|
issue 1
129-137
EN
Phenylacetic and retinoic acids are carboxyacidic cell differentiating agents displaying anticancer activities. We report on a new class of compounds including the 5'-esters of 2'-deoxyadenosine (dA) or 2-chloro-2'-deoxyadenosine (cladribine, 2CdA) and the aforementioned acids. The rationale behind the synthesis of these esters was that if they are hydrolyzed inside the lymphoid cells, either dA will be removed from the intracellular environment by deamination, or 2CdA will be phosphorylated and accumulated. In either case targetted delivery of the differentiating agent to the lymphoid cells may be envisaged. The said compounds were synthesized by the Mitsunobu procedure employing triphenylphosphine and azadicarboxylic acid esters, and their stability was tested against various esterases. Esters of dA and 2CdA with phenylacetic acids were found to be resistant to enzymatic hydrolysis, whereas those with retinoic acids were efficiently hydrolyzed by commercially available hepatic esterase as well as by esterases present in the blood plasma and in diluted human lymphocyte lysate. Susceptibility to enzymatic hydrolysis was found to be a prerequisite of cytotoxic and/or differentiating activity of these esters in leukemic cell lines.
5
Content available remote

Inhibition of DNA repair glycosylases by base analogs and tryptophan pyrolysate, Trp-P-1.

76%
Speina E., Cieśla J. M., Grąziewicz M.-A., Laval J., Kazimierczuk Z., Tudek B.
|
2005
|
vol. 52
|
issue 1
167-178
EN
DNA base analogs, 2,4,5,6-substituted pyrimidines and 2,6-substituted purines were tested as potential inhibitors of E. coli Fpg protein (formamidopyrimidine -DNA glycosylase). Three of the seventeen compounds tested revealed inhibitory properties. 2-Thioxanthine was the most efficient, inhibiting 50% of 2,6-diamino-4-hydroxy-5N-methyl-formamidopyrimidine (Fapy-7MeG) excision activity at 17.1 μM concentration. The measured Kgi was 4.44 ± 0.15 μM. Inhibition was observed only when the Fpg protein was first challenged to its substrate followed by the addition of the base analog, suggesting uncompetitive (catalytic) inhibition. For two other compounds, 2-thio- or 2-oxo-4,5,6-substituted pyrimidines, IC50 was only 343.3 ± 58.6 and 350 ± 24.4 μM, respectively. No change of the Fpg glycosylase activity was detected in the presence of Fapy-7MeG, up to 5 μM. We also investigated the effect of DNA structure modified by tryptophan pyrolysate (Trp-P-1) on the activity of base excision repair enzymes: Escherichia coli and human DNA glycosylases of oxidized (Fpg, Nth) and alkylated bases (TagA, AlkA, and ANPG), and for bacterial AP endonuclease (Xth protein). Trp-P-1, which changes the secondary DNA structure into non-B, non-Z most efficiently inhibited excision of alkylated bases by the AlkA glycosylase (IC50 = 1 μM). The ANPG, TagA, and Fpg proteins were also inhibited although to a lesser extent (IC50 = 76.5 μM, 96 μM, and 187.5 μM, respectively). Trp-P-1 also inhibited incision of DNA at abasic sites by the β-lyase activity of the Fpg and Nth proteins, and to a lesser extent by the Xth AP endonuclease. Thus, DNA conformation is critical for excision of damaged bases and incision of abasic sites by DNA repair enzymes.
6
Content available remote

Synthesis, antiprotozoal and antibacterial activity of nitro- and halogeno-substituted benzimidazole derivatives.

76%
Kazimierczuk Z., Upcroft J. A., Upcroft P., Górska A., Starościak B., Laudy A.
|
2002
|
vol. 49
|
issue 1
185-195
EN
Two series of benzimidazole derivatives were sythesised. The first one was based on 5,6-dinitrobenzimidazole, the second one comprises 2-thioalkyl- and thioaryl-substituted modified benzimidazoles. Antibacterial and antiprotozoal activity of the newly obtained compounds was studied. Some thioalkyl derivatives showed remarkable activity against nosocomial strains of Stenotrophomonas malthophilia, and an activity comparable to that of metronidazole against Gram-positive and Gram-negative bacteria. Of the tested compounds, 5,6-dichloro-2-(4-nitrobenzylthio)-benzimidazole showed the most distinct antiprotozoal activity.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.