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Częstochowa, Poland

Zawidlak-Wegrzynska B.,Polish Academy of Sciences | Kawalec M.,Polish Academy of Sciences | Bosek I.,Polish Academy of Sciences | Luczyk-Juzwa M.,Polish Academy of Sciences | And 9 more authors.
European Journal of Medicinal Chemistry

Synthesis of novel conjugates of the non-steroidal anti-inflammatory drug - ibuprofen with nontoxic oligo(3-hydroxybutyrate) (OHB) is described. Presented results indicate that anionic ring-opening polymerization of (R,S)-β-butyrolactone initiated with an alkali metal salt of (S)-(+)-2-(4-isobutylphenyl)propionic acid (ibuprofen) may constitute a convenient method of conjugation of selected drugs with biodegradable OHB. Furthermore using the MTT cell proliferation assay we demonstrated that ibuprofen conjugated with OHB exhibited significantly increased, as compared to free ibuprofen, potential to inhibit proliferation of HT-29 and HCT 116 colon cancer cells. However, the conjugates of ibuprofen and OHB are less toxic as was shown in oral acute toxicity test in rats. Although the mechanism of antiproliferative activity of ibuprofen-OHB conjugates (Ibu-OHB) has to be established, we suggest that partially it can be related to more effective cellular uptake of the conjugate than the free drug. This assumption is based on the observation of much more efficient accumulation of a marker compound - OHB conjugated with fluorescein, in contrast to fluorescein sodium salt, which entered cells inefficiently. Further characterization of biological properties of the ibuprofen-OHB conjugates would provide insight into the mechanism of their antiproliferative effect and assess the potential relevance of their anticancer activity. © 2010 Elsevier Masson SAS. All rights reserved. Source

Owsianik K.,Polish Academy of Sciences | Wieczorek W.,Technical University of Lodz | Balinska A.,Jan Dlugosz Academy | Mikolajczyk M.,Polish Academy of Sciences
Heteroatom Chemistry

Sulfonium ylides derived from chiral N,N′-substituted (benzyl, isopropyl, neopentyl) phosphonamides were prepared by reacting appropriate chiral diamidophosphites with potassium hydride and chloromethyl methyl sulfide, and then with methyl iodide in the presence AgBF4 to give the corresponding sulfonium salts in high yields. One of them was analyzed by X-ray crystallography. The salts upon treatment with different bases (LithiumDiisopropylAmine, BuLi, K2CO3) were converted in situ into ylides, which were reacted with activated olefins to produce phosphonocyclopropanes as a mixture of two diastereoisomers with moderate-to-high diastereoselectivities. © 2014 Wiley Periodicals, Inc. Source

Szyrej M.,Jan Dlugosz Academy | Wieczorek W.,Technical University of Lodz | Wozniak L.A.,Medical University of Lodz

Phenylamino (diphenyl)phosphine selenide 1 was synthesized and analyzed by X-ray. The analysis revealed a deformation of the phosphorus tetrahedron, the planar geometry around the nitrogen atom, and the torsion angle Se1-P1-N1-C11, corresponding to a synclinal conformation (-46.7(4)). It has been postulated that the conformation of 1 is stabilized by short intramolecular C-H⋯N, C-H⋯Se interactions, which generate rings of motifs S(5) and aromatic hydrogen bonds C-H⋯π. The crystal structure is stabilized by the weak N-H⋯Se intermolecular interactions, generating infinite chains, parallel to the c axis, of graph-set motif C(4). Additionally, there have been observed the C-H⋯π interactions, connecting chains N-H⋯Se into the sheet, parallel to (100), producing binary graph set N2 = C 22(10) (with ab sequence) and N2 = R 44(24) motifs (with abab sequence). The weak π⋯π interactions stack the layers in the crystal lattice. © ARKAT-USA, Inc. Source

Tikhonenko O.M.,Jan Dlugosz Academy
Automation and Remote Control

Consideration was given to a processor-sharing system with heterogeneous customers serviced by system resources of two types: the first, discrete, type necessarily consists of an integer number N of units (servers), and the second type (memory) may be discrete or continuous. The customer type is defined by the number of units of the first-type resources required to service it. In addition to the need for the first-type resource, each customer is characterized by a certain volume, that is, the amount of the second-type resource required to service it. The total amount of customers (total busy resource of the second type) in the system is limited by a certain positive value (memory space) V . The customer volume and its length (amount of work required to service it) are generally dependent. Their joint distribution also depends on the customer type. For this system, the stationary distribution of the number of customers sojourning in the system and the probabilities of losing customers of each type were determined. © Pleiades Publishing, Ltd., 2010. Source

Rahmonov O.,University of Silesia | Kowalski W.J.,Jan Dlugosz Academy | Bednarek R.,Nicolaus Copernicus University
Eurasian Soil Science

The composition of the soil organic matter in soil developing under the influence of vegetation during the primary succession in the poor sandy area was investigated. The Curie-point pyrolysis method coupled with gas chromatographic separation and mass spectrometric identification of pyrolysates was applied during the investigation. A comparison of occurrence and diversity in composition of organic compounds in plant tissues and humus horizon of soils under the communities of coniferous forest series in the initial stages and phases was carried out. A large diversity of organic compounds under Algae-Cyanophyta communities, biological soil crusts and Polytrichum piliferum was noticed. A clear differentiation in the composition of the soil organic matter at different phases of succession under predominating communities with cryptogamous and vascular plants was observed. The analysis of organic compounds in plant tissues was found to facilitate the determination of origin of various groups of organic compounds in the soil. The results obtained from the Curie point pyrograms in the humus horizon (A) under grasses (Corynephorus canescens, Koeleria glauca) differed from the pyrolysates obtained under Algae-Cyanophyta communities. The polysaccharide derivates are more frequent in the pyrolysis products under algae, grasses (Corynephorus canescens, Koeleria glauca) and mosses than under Pinus sylvestris. In the beginning of the terminal stage of succession, lignin, phenols and aliphatic substances, prevailed over the polysaccharide derivates in the humus horizon. © 2010 Pleiades Publishing, Ltd. Source

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