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Korać Jelena Todorović Nina Zakrzewska Joanna Žižić Milan Spasojević Ivan 《Structural chemistry》2018,29(5):1533-1541
Structural Chemistry - Epinephrine (Epi) is a physiologically important catecholamine. Molecular conformation of Epi controls the interactions with other molecules and its biological effects. There... 相似文献
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Milan Jakubek Zdeněk Kejík Robert Kaplánek Hana Veselá David Sýkora Pavel Martásek 《Supramolecular chemistry》2018,30(3):218-226
Perimidine-based chelators 1 and 2 were prepared, and their structures were confirmed by 1H and 13C NMR, MS spectroscopy and elemental analysis. These compounds were studied as specific synthetic receptors for the recognition of transition metal ions. They exhibited high affinity and selectivity towards Cu(II) ions. The conditional binding constants, linear dynamic range and detection limit were determined by UV–vis spectroscopy. These parameters demonstrated high potential of the prepared synthetic receptors for the recognition and determination of Cu(II) ions. The minimum detectable concentrations of Cu(II) ions for the synthetic receptors 1 and 2 were 270 and 75 nM (R 2 = 0.9915 and 0.9964) in aqueous medium (water/DMSO; 99:1 (v/v)), respectively. 相似文献
74.
Marija S. ?iri? Milan Lj. Zlatanovi? Mi?a S. Stankovi? Ljubica S. Velimirovi? 《Applied mathematics and computation》2012,218(12):6648-6655
In this paper geodesic mappings of equidistant generalized Riemannian spaces are discussed. It is proved that each equidistant generalized Riemannian space of basic type admits non-trivial geodesic mapping with preserved equidistant congruence. Especially, there exists non-trivial geodesic mapping of equidistant generalized Riemannian space onto equidistant Riemannian space. An example of geodesic mapping of an equidistant generalized Riemannian spaces is presented. 相似文献
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Milan Melník Peter Mikuš Ivan Malík 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1015-1019
AbstractIn this review structural parameters of forty complexes with an inner coordination sphere of Pt(η2-P2L)(η2-S2L) are analyzed and classified These complexes crystallize in three crystal systems: orthorhombic (four examples), triclinic (six examples) and monoclinic (thirty examples). The organodiphosphines create four- (PCP), five- (PC2P), six- (PC3P) and seven- (PC4P) membered metallocyclic rings with mean P-Pt-P bite angle values of 72.5° (PCP) < 85.3° (PC2P) < 93.0° (PC3P) < 97.4° (PC4P). The dithiolates create four- (SCS), five- (SC2S), six- (SC3S; SCSCS; SPNPS; SPCPS) and seven- (SC4S) membered metallocyclic rings with mean S-Pt-S bite angle values of 74.5° (SCS) < 85.8° (SCSCS) < 87.0° (SPNPS) < 89.0° (SC2S) < 92.3° (SC4S) < 93.5° (SC3S) < 97.5° (SPCPS). The mean Pt-P and Pt-S bond distances are 2.257 and 2.328?Å, respectively. The data are compared with those found in complexes with inner coordination spheres of Pt(PL)2(SL)2, Pt(PL)2(η2-S2L) and Pt(η2-P2L)(SL)2. 相似文献
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Violeta Marković Svetlana Marković Ana Janićijević Marko V. Rodić Vukadin M. Leovac Nina Todorović Snežana Trifunović Milan D. Joksović 《Structural chemistry》2013,24(6):2127-2136
A study on the synthesis and mechanistical aspects of formation of 3-methyl-5-oxo-3-pyrazolin-1-carboxamide (MOPC) starting from S-methylisothiosemicarbazide hydrogen iodide and methyl acetoacetate was performed. In the alkaline aqueous solution, the intermediate methyl acetoacetate S-methylisothiosemicarbazone undergoes substitution of CH3S? anion by hydroxide anion, cyclization, carbanion formation, and elimination of methanol, thus yielding corresponding Na-enolate salt of pyrazol-5-one derivative. The structure of the compound obtained after protonation of the formed enolate salt was determined by means of spectroscopic techniques and single-crystal X-ray diffraction analysis. The mechanism of conversion of methyl acetoacetate S-methylisothiosemicarbazone into MOPC was investigated by means of the B3LYP functional, and it was found that the reaction is thermodynamically controlled. 相似文献
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Tomas Bertok Pavol Gemeiner Milan Mikula Peter Gemeiner Jan Tkac 《Mikrochimica acta》2013,180(1-2):151-159
We report on an ultrasensitive label-free lectin-based impedimetric biosensor for the determination of the sialylated glycoproteins fetuin and asialofetuin. A sialic acid binding agglutinin from Sambucus nigra I was covalently immobilised on a mixed self-assembled monolayer (SAM) consisting of 11-mercaptoundecanoic acid and 6-mercaptohexanol. Poly(vinyl alcohol) was used as a blocking agent. The sensor layer was characterised by atomic force microscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. The biosensor exhibits a linear range that spans 7 orders of magnitude for both glycoproteins, with a detection limit as low as 0.33 fM for fetuin and 0.54 fM for asialofetuin. We also show, by making control experiments with oxidised asialofetuin, that the biosensor is capable of quantitatively detecting changes in the fraction of sialic acid on glycoproteins. We conclude that this work lays a solid foundation for future applications of such a biosensor in terms of the diagnosis of diseases such as chronic inflammatory rheumatoid arthritis, genetic disorders and cancer, all of which are associated with aberrant glycosylation of protein biomarkers. Figure
Key aspects of the biosensor: 1) mixed SAM formation, 2) immobilisation of lectin & blocking and 3) a glycoprotein recognition. 相似文献