Synthesis, characterization and cytotoxic activity of new diorganotin(IV) complexes of <i>N</i>‐(3,5‐dibromosalicylidene)tryptophane

Abstract

Abstract Four new diorganotin(IV) complexes of N ‐(3,5‐dibromosalicylidene)tryptophane, R 2 Sn[3,5‐Br 2 ‐2‐OC 6 H 2 CHNCH(CH 2 Ind)COO] [Ind = 3‐indolyl; R = Et (1); n ‐Bu (2); Cy (3); Ph (4)], were synthesized and characterized by elemental analysis and IR, NMR ( 1 H, 13 C and 119 Sn) spectra. The crystal structures of complexes 1–3 were determined by X‐ray single crystal diffraction. The tin atom is five‐coordinated and its coordination geometry is best described as an intermediate between trigonal bipyramidal and square pyramidal. Intermolecular weak interactions in the complexes 1–3 connect molecules into a one‐dimensional helical chain and a two‐dimensional array. The dibutyltin complex 2 has potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complex 1 displays weak cytotoxic activity. Copyright © 2011 John Wiley &amp; Sons, Ltd.