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A family of three discrete organoantimony(III)-functionalized heteropolyanions--[Na{2-(Me2HN+CH2)C6H4SbIII}AsIII2W19O67(H2O)]10- (1), [{2-(Me2HN+CH2)C6H4SbIII}2AsIII2W19O67(H2O)]8- (2), and [{2-(Me2HN+CH2)C6H4SbIII}{WO2(H2O)}{WO(H2O)}2(B-β-AsIIIW8O30)(B-α-AsIIIW9O33)2]14- (3)--have been prepared by one-pot reactions of the 19-tungstodiarsenate(III) precursor [AsIII2W19O67(H2O)]14- with 2-(Me2NCH2)C6H4SbCl2. The three novel polyanions crystallized as the hydrated mixed-alkali salts Cs3KNa6[Na{2-(Me2HN+CH2)C6H4SbIII}AsIII2W19O67(H2O)]·43H2O (CsKNa-1), Rb2.5K5.5[{2-(Me2HN+CH2)C6H4SbIII}2AsIII2W19O67(H2O)]·18H2O·Me2NCH2C6H5 (RbK-2), and Rb2.5K11.5[{2-(Me2HN+CH2)C6H4SbIII}{WO2(H2O)}{WO(H2O)}2(B-β-AsIIIW8O30)(B-α-AsIIIW9O33)2]·52H2O (RbK-3), respectively. The number of incorporated {2-(Me2HN+CH2)C6H4SbIII} units could be tuned by careful control of the experimental parameters. Polyanions 1 and 2 possess a dimeric sandwich-type topology, whereas 3 features a trimeric, wheel-shaped structure, representing the largest organoantimony-containing polyanion. All three compounds were fully characterized in the solid state via single-crystal X-ray diffraction (XRD), infrared (IR) spectroscopy, and thermogravimetric analysis, and their aqueous solution stability was validated by ultraviolet-visible light (UV-vis) and multinuclear (¹H, 13C, and 183W) nuclear magnetic resonance (NMR) spectroscopy. Effective inhibition against six different types of bacteria was observed for 1 and 2, and we could extract a structure-bioactivity relationship for these polyanions. [ABSTRACT FROM AUTHOR]

Two tetra-antimony(III)-bridged, sandwich-type 18-tungsto-2-arsenates(V), [(LSbIII)4(A-α-AsVW9O34)2]10- (L = Ph (1), OH (2)), were prepared and fully characterized in the solid state and in solution. Both polyanions are stable in aqueous physiological medium for at least 24 h (at concentrations &#8805=;2.5 × 10-6 M). Despite the presence of an isostructural tetra-antimony(III) motif in 1 and 2, distinctly different antibacterial activity was observed for both polyanions. The minimum inhibitory concentrations (MIC) of 1 (7.8-62.5 μg/mL) is lower than for any other organoantimony(III)-containing polyoxometalate reported to date. [ABSTRACT FROM AUTHOR]

The novel Ti2-containing, sandwich-type 18-tungsto-2-arsenate(III) [(TiIVO)2(α-AsIIIW9O33)2]14- (1) was successfully synthesized by the reaction of [TiO]2+ species with [α-AsIIIW9O33]9-. The monolacunary polyanion 1 is solution-stable, and a further reaction with 1 equiv of phenylantimony(III) dichloride resulted in [C6H5SbIII(TiIVO)2(α-AsIIIW9O33)2]12- (2). Both polyanions 1 and 2 were structurally characterized in the solid state and solution. Electrochemical studies were also performed on both polyanions. [ABSTRACT FROM AUTHOR]