Diorganotin Complexes of N-[4-(Diethylamino)salicylidene]-(L)-tryptophane: Syntheses, Structures and Properties

Four chiral diorganotin complexes of N-[4-(diethylamino)salicylidene]-(L)-trypto-phane, R2Sn[4-(Et2N)-2-OC6H3CH=NCH(CH(2)Ind)COO] (Ind = 3-indolyl; R = Me (1); Et, (2); n-Bu (3); Cy (cyclohexyl) (4)), have been synthesized and characterized by elemental analysis, IR, and H-1 and C-13 NMR spectra. The crystal structures of 1 center dot CH3OH center dot CHCl3, 2, 3 center dot CH3OH and 4 center dot CH3CH2OH have been determined by single-crystal X-ray diffraction. The complexes crystallize in orthorhombic system with P2(1)2(1)2(1) space group, and the tin atoms are in distorted trigonal bipyramidal geometry and form five- and six-membered chelate rings with the chiral ONO tridentate ligand N-[4-(diethylamino)salicylidene]-(L)-tryptophane. In the complexes, the molecules are connected into one-dimensional supramolecular chain by intermolecular N-H center dot center dot center dot O-H center dot center dot center dot O=C or N-H center dot center dot center dot O-C hydrogen bonds. The fluorescence spectrum indicates that the complexes may be explored for potential blue luminescent materials. Bioassay results show that 3 and 4 belong to the efficient cytostatic agents against A549 human tumor cell.