Organotin(IV) complexes with various donor ligands and their cytotoxicity against tumour cell lines. Part(I): R2SnCl2 with Schiff bases; unusual CN bond cleavage of the bases and X-ray structures of the ionic products formed

• Published in: Applied organometallic chemistry 2003-12, Vol.17 (12), p.891-897
• Main Authors: Al-Allaf, Talal A. K., Rashan, Luay J., Stelzner, Axel, Powell, Douglas R.
• Format: Article
• Language: English
• Subjects: Antineoplastic agents; Biological and medical sciences; Chemistry; complexes; Condensed matter: structure, mechanical and thermal properties; Coordination compounds; cytotoxicity; Exact sciences and technology; General aspects; Inorganic chemistry and origins of life; ionic products; Medical sciences; Organotin(IV); Pharmacology. Drug treatments; Physics; Preparations and properties; Schiff bases; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; X-ray structures
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.545

Several Schiff bases derived from salicylaldehyde and aminopyridines were found to coordinate with Me2SnCl2 in 1:1 or 1:2 (tin:base) molar ratio in diethylether, depending on the nature of the Schiff base used, to form complexes of the general formula Me2SnCl2·L or Me2SnCl2·2L respectively. These Schiff bases coordinate with Ph2SnCl2 in a similar manner, but if the reaction is carried out in chloroform or if the product formed in ether is dissolved in chloroform then colourless to pale yellow crystals precipitated. The latter were analysed and found to be due to the ionic compounds [H2NpyN–H+]2 [Ph2SnCl4]2− which were formed as a result of an unusual cleavage of the CN bond of the Schiff bases. The Schiff bases, their Me2SnCl2 complexes and the ionic compounds were analyzed physicochemically and spectroscopically. The crystal structures of two of the ionic compounds showed that the cation [H2NpyN–H+] binds with the anion [Ph2SnCl4]2− via hydrogen bonds. The Schiff bases, their Me2SnCl2 complexes and the ionic compounds were screened against the three tumour cell lines, L929, K562 and HeLa, and the results were compared with those of the anticancer drugs, cisplatin, carboplatin and oxaliplatin. Copyright © 2003 John Wiley & Sons, Ltd.