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171.
Vesna Tumbas Šaponjac Dragana Četojević-Simin Gordana Ćetković Jasna Čanadanović-Brunet Sonja Djilas Anamarija Mandić Aleksandra Tepić 《Central European Journal of Chemistry》2014,12(3):377-385
Ground spice paprika was extracted with hexane, by conventional Soxhlet procedure (SX oleoresin), and with supercritical carbon dioxide at three different pressures — 20, 30 and 40 MPa (SF20, SF30 and SF40 oleoresins). The effect of extraction method and conditions on the colour intesity of paprika oleoresins, content of α-tocopherol, as well as antioxidant and antiproliferative activity was examined. Hexane showed highest selectivity for paprika pigments (886.02 ASTA), while α-tocopherol showed highest solubility (3846.9 mg kg?1) in supercritical carbon dioxide at 20 MPa. All paprika oleoresins exhibited good superoxide anion radical scavenging activity SF30 being the best superoxide anion radical scavenger. Cell growth activity was evaluated in vitro in human cell lines:cervix epitheloid carcinoma (HeLa), breast adenocarcinoma (MCF7) and colon adenocarcinoma (HT-29). The highest antiproliferative activity was exhibited by SX in MCF7 cell line (IC50=14.28 mg mL?1). Extract SF40 produced significant and selective antiproliferative action towards HeLa cell line. These results suggest that paprika oleoresins, due to high antiradical and tumor cell-inhibiting activity, can be regarded as functional food ingredients. 相似文献
172.
New β-3-thienyl (8) and β-3-furyl derivatives of o-divinylbenzene (9) have been synthesised and their photochemical behaviour compared with 2-thienyl (7) and 2-furyl derivatives (2). Whereas the β-(2-heteroaryl) substituted o-divinylbenzenes (7 or 2) give only bicyclo[3.2.1]octadiene structure (14 or 1) by 1,6-ring closure of the biradical intermediate, β-(3-heteroaryl) substituted o-divinylbenzenes (8 or 9) give bicyclo[3.2.1]octadiene structure (23 or 24) and bicyclo[2.1.1]hexene structure (25 or 26) by 1,6- and 1,4-ring closure, respectively. This photochemical approach provides a simple method to 2,3- and 3,2-fused thiophene and furan polycyclic compounds. 相似文献
173.
Philipp Schmeinck Dragana Sretenović Jasper Guhl Dr. Ralf Kühnemuth Prof. Dr. Claus A. M. Seidel Prof. Dr. Christel M. Marian Prof. Dr. Markus Suta Prof. Dr. Christian Ganter 《欧洲无机化学杂志》2023,26(27):e202300416
The anionic diamido N-heterocyclic carbene 1 is used to prepare a series of linear as well as trigonal, heteroleptic CuI complexes with small molecular ligands such as pyridine derivatives or triphenylphosphine. A key role lies in the versatile precursor for these complexes, a moisture- and air-stable 1D coordination polymer [1 ⋅ Cu] n composed of only the NHC ligand and CuI, such that the copper is linearly coordinated by the carbene carbon atom and one oxygen atom of the backbone of the carbene. This polymer can easily be cleaved into monomeric complexes by addition of the desired ligand to dispersions of the polymer in dichloromethane. In solution, the complexes are in equilibrium with this highly insoluble polymer and free ligand. Thus, analytical and spectroscopical experiments with the compounds are limited to their crystalline state, characterized by single crystal X-ray diffraction experiments. Some of the complexes exhibit visible luminescence in the solid state upon irradiation with ultraviolet light. The spectral features (emission wavelength, Stokes shift, width of the emission band, vibrational fine structure) significantly differ among the complexes. Quantum mechanical computations reveal a subtle interplay of several factors such as coordination number and charge transfer character of the emissive state. 相似文献
174.
Árpád Baricz Dragana Jankov Tibor K. Pogány 《Journal of Mathematical Analysis and Applications》2012,388(2):716-724
Complete monotonicity, Laguerre and Turán type inequalities are established for the so-called Krätzel function , defined by where and . Moreover, we prove the complete monotonicity of a determinant function of which entries involve the Krätzel function. 相似文献
175.
In this paper the conditions under which the weighted generalized inversesA (1,3M), A(1,4N), A M,N Dg andA d,W can be expressed in Banachiewicz-Schur form are considered and some interesting results are established. These results contribute to verify recent results obtained by J. K. Baksalary and G. P. Styan [2] and Y. Wei [15] and these extend their works. 相似文献
176.
Dragana Neradovic Wouter L. J. Hinrichs Jantien J. Kettenes-van den Bosch Wim E. Hennink 《Macromolecular rapid communications》1999,20(11):577-581
N-isopropylacrylamide (NIPAAm) was copolymerized with 2-hydroxyethyl methacrylate-monolactate (HEMA-monolactate). With increasing HEMA-monolactate content in the copolymer, the lower critical solution temperature (LCST) decreases. During incubation in an aqueous solution, the lactate groups are released by hydrolysis, by which the copolymer is converted into poly(NIPAAm-co-HEMA). By this process, the hydrophilicity of the copolymer increases, resulting in increased LCST values. 相似文献
177.
Mirela Sarbu Dragana Fabris
eljka Vukeli David E. Clemmer Alina D. Zamfir 《Molecules (Basel, Switzerland)》2022,27(3)
Gangliosides (GGs) represent an important class of biomolecules associated with the central nervous system (CNS). In view of their special role at a CNS level, GGs are valuable diagnostic markers and prospective therapeutic agents. By ion mobility separation mass spectrometry (IMS MS), recently implemented by us in the investigation of human CNS gangliosidome, we previously discovered a similarity between GG profiles in CSF and the brain. Based on these findings, we developed IMS tandem MS (MS/MS) to characterize rare human CSF glycoforms, with a potential biomarker role. To investigate the oligosaccharide and ceramide structures, the ions detected following IMS MS separation were submitted to structural analysis by collision-induced dissociation (CID) MS/MS in the transfer cell. The IMS evidence on only one mobility feature, together with the diagnostic fragment ions, allowed the unequivocal identification of isomers in the CSF. Hence, by IMS MS/MS, GalNAc-GD1c(d18:1/18:1) and GalNAc-GD1c(d18:1/18:0) having both Neu5Ac residues and GalNAc attached to the external galactose were for the first time discovered and structurally characterized. The present results demonstrate the high potential of IMS MS/MS for biomarker discovery and characterization in body fluids, and the perspectives of method implementation in clinical analyses targeting the early diagnosis of CNS diseases through molecular fingerprints. 相似文献
178.
In many papers concerning properties of generalized inverses in different settings, we can find the results with many redundant instances of assuming regularity of certain elements. We have made an effort to widen the range of applicability of concrete results by considering more general cases of the problems without imposing any such additional assumptions. This was the main motivation for this paper, and we present several significant improvements of the reverse order laws on and -inverses in the ring setting. 相似文献