Syntheses, properties and biological activity of organogermanium substituted heteropolytungstates

Six new compounds [(RGe)XW11O39]n− (R = HOOCCH2CH2, HOOCCH2(m-NO2C6H4)CH); X = Ge, Si, P) have been prepared and their Keggin structures determined by elementary analysis, IR, UV, 1H NMR and 183W NMR spectrometry. The results show that the complexes retain Keggin structure with organogermanium group grafting on the polyoxometalate surface. The complexes exhibit antitumoral activity in vitro as shown by MTT experiment.