Triorganotin(IV) complexes with substituted benzeneseleninic acids: syntheses, characterization, crystal structures, and antitumor activity

Nine new organotin(IV) selenites have been prepared by the reaction of 2-methylbenzeneseleninic acid, 2-methoxybenzeneseleninic acid, 4-isopropylbenzeneseleninic acid, and the corresponding triorganotin(IV) chloride with sodium ethoxide in methanol. The complexes have been characterized by elemental analysis, FT-IR, (H-1, C-13, and Sn-119) NMR spectroscopy, and thermogravimetric analysis. Except for 3, 6, and 9, all of the complexes were also characterized by X-ray crystallography diffraction analyses. The structural analyses reveal that 1, 2, 4, 5, 7, and 8 exhibit 1-D infinite chain structures which are generated by bidentate oxygen atoms and five-coordinated tin. Complex 5 forms a 2-D organotin framework linked by intermolecular C-H center dot center dot center dot O interactions. Additionally, 1 and 2 were tested for antitumor activity in vitro.