Synthesis, structural characterization and bioassay screening of dimeric bis[dicarboxylatotetraorganodistannoxanes

Abstract

Reaction of bis(pyrazol-1-yl)acetic acid with n-Bu2SnO in a 1:1 molar ratio gives dimeric bis[dicarboxylatotetraorganodistannoxanes], {[(n-Bu)2(Pz2CHCO2)Sn]2O}2 (Pz = pyrazol-1-yl or 3,5-dimethylpyrazol-1-yl), which are characterized by IR and NMR (1H, 13C and 119Sn) spectra and elemental analyses. The X-ray crystal structure analyses indicate that {[(n-Bu)2(Pz2CHCO2)Sn]2O}2 is a centrosymmetric dimer with a cyclic Sn2O2 unit, in which each tin atom is situated in a distorted trigonal bipyramidal geometry. In addition, bis(3,5-dimethylpyrazol-1-yl)acetic acid in the solid state forms a dimer through two intermolecular OH···N hydrogen bonds. These organotin derivatives display low fungicide, insecticide and miticide activities, but display certain cytotoxicities for Hela cells in vitro. Copyright © 2005 John Wiley & Sons, Ltd.