News Interviews: Clayman and Heritage’s The News Interview

News interviews: Clayman and Heritage’s ‘The News Interview

Toxicity evaluation of two polyoxotungstates with anti-acetylcholinesterase activity

A toxicity evaluation of two Keggin-type heteropolytungstates, K-7[Ti2PW10O40].6H(2)O and K6H [SiV3W9O40].3H(2)O, with different inhibitory potencies toward acetylcholinesterase activity (IC50 values of 1.04 x 10(-6) and 4.80 x 10(-4) mol/L, respectively) was performed. Wistar albino rats were orally treated with single doses (5 and 50 mg/kg) of both investigated compounds. The biochemical parameters of renal (serum urea and creatinine) and liver function (direct and total bilirubin, alanine transaminase, and aspartate aminotransferase) were determined after 24 h and 14 days. A histopathological analysis of liver tissue was carried out 14 days after the polyoxotungstate administration. Both applied doses of the investigated compounds did not induce statistically significant alterations of the renal function markers. However, the polyoxotungstate treatment caused an increase in the activities of serum alanine transaminase and aspartate aminotransferase in a time- and concentration -dependent manner, although statistically significant changes in bilirubin concentrations were not observed. Furthermore, the detected hepatotoxic effect was confirmed by histhopathological analysis that suggested some reversible liver tissue damage two weeks after the treatment, especially in the case of K6H [SiV3W9O40]-3H(2)O. Accordingly, the toxicity of these two polyoxotungstates with anti-acetylcholinesterase effect cannot be considered as a severe one, but their potential clinical application would require a more complex toxicological study

Dithallium(III)-Containing 30-Tungsto-4-phosphate, [Tl2Na2(H2O)2(P2W15O56)2]16-: Synthesis, Structural Characterization, and Biological Studies

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Mixed-Valent Mn-16-Containing Heteropolyanions: Tuning of Oxidation State and Associated Physicochemical Properties

The two 16-manganese-containing, Keggin-based 36-tungsto-4-silicates [(Mn10Mn6O6)-Mn-III-O-II(OH)(6)(PO4)(4)(A-alpha-SiW9O34)(4)](28-) (1) and [(Mn4Mn12II)-Mn-III(OH)(12)(PO4)(4)(A-alpha-SiW9O34)(4)](28-) (2) have been prepared by reaction of the trilacunary Keggin precursor [A-alpha-SiW9O34](10-) with either Mn(OOCCH3)(3)center dot 2H(2)O (for 1) or MnCl2 center dot 4H2O (for 2), in aqueous phosphate solution at pH 9. Polyanions 1 and 2 comprise mixed-valent, cationic {(MnMnI6O6)-Mn-III-I-II(OH)(6)}(24+) and {(Mn10Mn6O6)-Mn-III-O-II(OH)(6)(PO4)(4) cores, respectively, encapsulated by four phosphate groups and four {SiW9} units in a tetrahedral fashion. Both polyanions were structurally and compositionally Characterized by single-crystal XRD, IR, therrnogravimetric analysis, and X-ray absorption,, spectroscopy. Furthermore, studies were performed probing, the magnetic, electrochemical, oxidation catalytic, and Li-ion battery performance of 1 and 2

Dithallium(III)-Containing 30-Tungsto-4-phosphate, [Tl Na (H O) (P W O ) ] : Synthesis, Structural Characterization, and Biological Studies

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Dithallium(III)-Containing 30-Tungsto-4-phosphate, [Tl₂Na₂(H₂O)₂(P₂W₁₅O₅₆)₂]^16–: Synthesis, Structural Characterization, and Biological Studies

Here we report on the synthesis and structural characterization of the dithallium­(III)-containing 30-tungsto<i>-</i>4-phosphate [Tl₂Na₂(H₂O)₂­{P₂W₁₅O₅₆}₂]^16– (<b>1</b>) by a multitude of solid-state and solution techniques. Polyanion <b>1</b> comprises two octahedrally coordinated Tl³⁺ ions sandwiched between two trilacunary {P₂W₁₅} Wells–Dawson fragments and represents only the second structurally characterized, discrete thallium-containing polyoxometalate to date. The two outer positions of the central rhombus are occupied by sodium ions. The title polyanion is solution-stable as shown by ³¹P and ^203/205Tl NMR. This was also supported by Tl NMR spectra simulations including several spin systems of isotopologues with half-spin nuclei (²⁰³Tl, ²⁰⁵Tl, ³¹P, ¹⁸³W). ²³Na NMR showed a time-averaged signal of the Na⁺ counter cations and the structurally bonded Na⁺ ions. ^203/205Tl NMR spectra also showed a minor signal tentatively attributed to the trithallium-containing derivative [Tl₃Na­(H₂O)₂­(P₂W₁₅O₅₆)₂]^14–, which could also be identified in the solid state by single-crystal X-ray diffraction. The bioactivity of polyanion <b>1</b> was also tested against bacteria and <i>Leishmania</i>