Synthesis,structural characterization and cytotoxic activity of diorganotin(IV) complexes of N‐(5‐halosalicylidene)‐α‐amino acid

Fourteen new diorganotin(IV) complexes of N‐(5‐halosalicylidene)‐α‐amino acid, R′₂Sn(5‐X‐2‐OC₆H₃CH?NCHRCOO) (where X = Cl, Br; R = H, Me, i‐Pr; R′ = n‐Bu, Ph, Cy), were synthesized by the reactions of diorganotin halides with potassium salt of N‐(5‐halosalicylidene)‐α‐amino acid and characterized by elemental analysis, IR and NMR (¹H, ¹³C and ¹¹⁹Sn) spectra. The crystal structures of Bu₂Sn(5‐Cl‐2‐OC₆H₃CH?NCH(i‐Pr)COO) and Ph₂Sn(5‐Br‐2‐OC₆H₃CH?NCH(i‐Pr)COO) were determined by X‐ray single‐crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five‐ and six‐membered chelate rings with the tridentate ligand. Bioassay results of a few compounds indicated that the compounds have strong cytotoxic activity against three human tumour cell lines, i.e. HeLa, CoLo205 and MCF‐7, and the activity decreased in the order Cy>n‐Bu>Ph for the R′ group bound to tin. Copyright © 2005 John Wiley & Sons, Ltd.