Publications by authors named "Anne Spasojevic-de Bire"

The influence of three functionalized hexavanadates (V): Na [VO{(OCH)CCH}], [H] [VO{(OCH)CCHOCOCHCH}] and [(CH)N] [VO{(OCH)CCHOOC(CH)-COOH} on Na/K-ATPase activity, was investigated in vitro. Including compounds already tested by Xu et al. (Journal of Inorganic Biochemistry 161 (2016) 27-36), all functionalized hexavanadates inhibit the activity of Na/K-ATPase in a dose-dependent manner but with different inhibitory potencies.

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Influence of 12-tungstophosphoric acid (WPA) on conversion of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) in the presence of Na/K-ATPase was monitored by P NMR spectroscopy. It was shown that WPA exhibits inhibitory effect on Na/K-ATPase activity. In order to study WPA reactivity and intermolecular interactions between WPA oxygen atoms and different proton donor types (D=O, N, C), we have considered data for WPA based compounds from the Cambridge Structural Database (CSD), the Crystallographic Open Database (COD) and the Inorganic Crystal Structure Database (ICSD).

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A high resolution X-ray diffraction study has been carried out on [(CH)N] [VO{(OCH)CCHOCCHCH}] (V6-C3) at 100 K. The V6 core possesses a negative charge, leading to a strong polarization of the anion. A nucleophilic region localized near the organic moiety and an electrophilic region in the vicinity of the V6 core provide an overall description of charge-transfer behavior.

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In vitro influence of five synthesized functionalized hexavanadates (V6) on commercial porcine cerebral cortex Na(+)/K(+)-ATPase activity has been studied. Dose dependent Na(+)/K(+)-ATPase inhibition was obtained for all investigated compounds. Calculated half maximal inhibitory concentration IC50 values, in mol/L, for Na(+)/K(+)-ATPase were 7.

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We have performed X-ray diffraction measurements on single crystals of Na(3)[V(10)O(28)](C(4)N(3)OH(5))(3)(C(4)N(3)OH(6))(3)·10H(2)O as a function of the temperature. When the sample is cooled, from room temperature to 100 K, we have observed additional peaks well indexed in P1, while the phase at room temperature crystallizes in P1. The molecular structure at 210 K indicates that the center of inversion is located between two cytosinium molecules, formally described with a charge of +0.

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The in vitro influence of decameric vanadate species on Na+/K+-ATPase, plasma membrane Ca2+-ATPase (PMCA)-calcium pump and ecto-ATPase activity, using rat synaptic plasma membrane (SPM) as model system was investigated, whereas the commercial porcine cerebral cortex Na+/K+-ATPase served as a reference. The thermal behaviour of the synthesized decavanadate (V10) has been studied by differential scanning calorimetry and thermogravimetric analysis, while the type of polyvanadate anion was identified using the IR spectroscopy. The concentration-dependent responses to V10 of all enzymes were obtained.

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We have synthesized and crystallized a cytosine-decavanadate compound, Na(3) [V(10)O(28)] (C(4)N(3)OH(5))(3)(C(4)N(3)OH(6))(3).10H(2)O, and its crystal structure has been determined from a single-crystal X-ray diffraction. A high resolution X-ray diffraction experiment at 210 K (in P1 space group phase) was carried out.

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The experimental electron density of the bis(thiosemicarbazide)zinc(II) dinitrate complex, [Zn(CH5N3S)2](NO3)2,was studied. The Hansen-Coppens multipole model was used to extract the electron density from high-resolution X-ray diffraction data collected at 100 K. Careful strategies were designed for the electron density refinements regarding the charge transfer between the anionic and the cationic parts of the complex.

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Both 7-carboxylato-8-hydroxy-2-methylquinolinium monohydrate, C11H9NO3.H2O, (I), and 7-carboxy-8-hydroxy-2-methylquinolinium chloride monohydrate, C11H10NO3+.Cl-.

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In connection with a total synthesis of cephalotaxine (1a), we have examined the addition of various nucleophilic reagents to [ABC] subunits 2 and 7 possessing a pyrrolobenzazepine core. In fact, this reaction implicates invariably the carbonyl group of 2. Regarding the reaction of 7 with nucleophiles, the most striking aspect is the complete lack of reactivity of the enaminonitrile moiety.

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Purpose: In the route of developing novel liquid phase formulations based on the encapsulation of busulfan into liposomes in nontoxic solvents, drug crystallization inevitably occurs. In order to better understand the reactivity of busulfan, the characterization of its molecular properties was therefore considered as a key point. Also, preliminary attempts to prevent crystallization using cyclodextrins were explored.

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The title complexes, catena-poly[[aqua(1,10-phenanthroline-kappa(2)N,N')cobalt(II)]-micro-benzene-1,4-dicarboxylato-kappa(2)O(1):O(4)], [Co(C(8)H(4)O(4))(C(12)H(8)N(2))(H(2)O)], (I), and catena-poly[[[(di-2-pyridyl-kappaN-amine)copper(II)]-micro-benzene-1,4-dicarboxylato-kappa(4)O(1),O(1'):O(4),O(4')] hydrate], [Cu(C(8)H(4)O(4))(C(10)H(9)N(3))].H(2)O, (II), take the form of zigzag chains, with the 1,4-benzenedicarboxylate ion acting as an amphimonodentate ligand in (I) and a bis-bidentate ligand in (II). The Co(II) ion in (I) is five-coordinate and has a distorted trigonal-bipyramidal geometry.

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