Synthesis and characterization of organotitanium substituted heteropolytungstosilicates and their biological activity

Tris, di‐( organotitanium) substituted tungstosilicates α,β ‐ (CpTi)3(SiW 9 037) 17– and γ‐[(CpTi)2(SiW 10 O 38 )] 6– were prepared by the reaction of C 2 TiC1 2 (Cp= η‐C 5 H 5 ) with a,β‐SiW 9 O9/34(noted α,β Siv 9 ,), γ‐SiWO8/36 (noted γ‐SiW 10 ) The products were characterized by means of elemental analysis, IR, 1 H NMR, 183 W NMR and polarography. 183 W NMR spectra of the complexes support the stoichiometry of the new heteropolyanions and the probable retention of the A‐XW 9 or γ‐SiWl O units. And the organotitanium substituted compounds showed promising in vitro antitumor activity in two of human tumor cell lines.