Stability Study of Hypervalent Tellurium Compounds in Aqueous Solutions

[Image: see text] Hypervalent tellurium compounds (telluranes) are promising therapeutical agents with negligible toxicities for some diseases in animal models. The C–Te bond of organotellurium compounds is commonly considered unstable, disfavoring their applicability in biological studies. In this study, the stability of a set of telluranes composed of an inorganic derivative and noncharged and charged organic derivatives was monitored in aqueous media with (1)H, (13)C, and (125)Te NMR spectroscopy and high-resolution mass spectrometry. Organic telluranes were found to be remarkably resistant and stable to hydrolysis, whereas the inorganic tellurane AS101 is totally converted to the hydrolysis product, trichlorooxytellurate, [TeOCl(3)](−), which was also observed in the hydrolysis of TeCl(4). The noteworthy stability of organotelluranes in aqueous media makes them prone to further structure–activity relationship studies and to be considered for broad biological investigations.