Synthesis and characterization of organotin-substituted heteropoly tungstosilicates and their biological activity I

Abstract

Tris(organotin)-substituted α,β-Keggin heteropoly-tungstosilicates α-[(RSn) 3SiW 9O 37] 7−, α-[(RSn) 3(SiW 9O 34) 2] 11−, β-[(RSn) 3SiW 9O 37] 7− and β-[(RSn) 3(SiW 9O 34) 2] 11− have been prepared by reaction of the β-methoxycarbonylethyltin, β-methoxycarbonyl(i)-propyltin, cyanoethyltin trichlorides with trivacant precursors α,β-SiW 9O 34 10−, respectively. The products were characterized by elemental analysis, IR, electrochemistry, 1H, 119Sn, and 183W NMR spectroscopy. 183W NMR spectra of the compounds consist of two lines with the intensity ratio 2:1 or 1:2, and demonstrated that α,β-[(RSn) 3(SiW 9O 37)] 7− have the Keggin structure and α,β-[(RSn) 3 (SiW 9O 34) 2] 11- have a sandwich structure. The title complexes display antitumoral activity in vitro.