Synthesis, structural characterization and cytotoxic activity of diorganotin(IV) complexes of <i>N</i>‐(5‐halosalicylidene)tryptophane

Abstract

Abstract Four new diorganotin(IV) complexes of N ‐(5‐halosalicylidene)tryptophane, R 2 Sn[5‐X‐2‐OC 6 H 3 CHNCH(CH 2 Ind)COO] [Ind = 3‐indolyl; R, X = Et, Cl ( 1 ); Et, Br( 2 ); n ‐Bu, Cl ( 3 ); n ‐Bu, Br ( 4 )], were synthesized and characterized by elemental analysis, IR and NMR ( 1 H, 13 C and 119 Sn) spectra. The crystal structures of complexes 1 – 3 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. Intermolecular weak interactions in 1–3 link molecules, respectively, into a two‐dimensional array, a one‐dimensional infinite chain and a one‐dimensional double‐chain supramolecular structure. Bioassay results of the compounds indicated that the dibutyltin complexes 3 and 4 have potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complexes 1 and 2 display weak cytotoxic activity. Copyright © 2008 John Wiley &amp; Sons, Ltd.