Comparative study of various polyols as complexing agents for the acidimetric titration of tungstate

Verchère, Jean‐François; Sauvage, Jean-Paul; Rapaumbya, Guy-Roland

doi:10.1039/an9901500637

Cited by 14 publications

(10 citation statements)

References 20 publications

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“…Elevation of KLF4 and EGR1 , both of which are well-established drivers of apoptosis, 66 , 67 by CPP-hnRNPK-RGG may occur via disruption of the binding and/or processing functions of hnRNPK on these transcripts, as has been reported elsewhere. 5 , 6 The mechanism of peptide-mediated increases in FOS transcripts that we observe is unclear, but this finding has been reported in cells undergoing apoptosis.…”

Section: Discussionsupporting

confidence: 57%

hnRNPK-derived cell-penetrating peptide inhibits cancer cell survival

Puvvula

Buczkowski

Moon

2021

Molecular Therapy - Oncolytics

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Section: Discussionsupporting

confidence: 57%

hnRNPK-derived cell-penetrating peptide inhibits cancer cell survival

Puvvula

Buczkowski

Moon

2021

Molecular Therapy - Oncolytics

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“…The literature did not set a threshold for the downfield shift exhibited by the coordinated carbon atoms. However, a minimum deshielding of 5 ppm was perceived while discussing tungsten and molybdenum complexes of carbohydrates. , normalC normalI normalS = δ ( c o m p l e x e d s u g a r ) − δ ( f r e e s u g a r ) …”

Section: Resultsmentioning

confidence: 99%

Elucidation of Metal–Sugar Complexes: When Tungstate Combines with d-Mannose

et al. 2023

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The control of metal−sugar complexes speciation in solution is crucial in an energy transition context. Herein, the formation of tungstate-mannose complexes is unraveled in aqueous solution using a multitechnique experimental and theoretical approach. 13 C nuclear magnetic resonance (NMR), as well as 13 C− 1 H and 1 H− 1 H correlation spectra, analyzed in the light of coordination-induced shift method and conformation analysis, were employed to characterize the structure of the sugar involved in the complexes. X-ray absorption near edge structure spectroscopy was performed to provide relevant information about the metal electronic and coordination environment. The calculation of 13 C NMR chemical shifts for a series of tungstate-mannose complexes using density functional theory (DFT) is a key to identify the appropriate structure among several candidates. Furthermore, a parametric study based on several relevant parameters, namely, pH and tungstate concentration, was carried out to look over the change of the nature and concentrations of the complexes. Two series of complexes were detected, in which the metallic core is either in a ditungstate or a monotungstate form. With respect to previous proposals, we identify two new species. Dinuclear complexes involve both αand β-furanose forms chelating the metallic center in a tetradentate fashion. A hydrate form chelating a ditungstate core is also revealed. One monotungstate complex appears at high pH, in which a tetrahedral tungstate center is bound to α-mannofuranose through a monodentate site at the second deprotonated hydroxyl group. This unequalled level of knowledge opens the door to structure−reactivity relationships.

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“…The W, and W2 signals appeared as doublets, showing apparently a single coupling 183W-'H with typical J values [8][9][10] Hz (Table III). Several other couplings might be suspected, because each tungsten atom was chelated by three carbon atoms, each of which possessed at least one hydrogen atom, and a small second coupling was indeed observed in some cases (/ = 1-2 Hz).…”

Section: Methodsmentioning

confidence: 96%