Synthesis, characterization, and cytotoxic activity of tricyclohexyltin(IV) carboxylates derived from cyclic dicarboxylic anhydrides

Abstract

Some tricyclohexyltin(IV) carboxylates, HOOC–R–COOSn(c-C₆H₁₁)₃ (1) and (c-C₆H₁₁)₃SnOOC–R–COOSn(c-C₆H₁₁)₃ (2) [R = 1,2-C₆H₄ (a), 1,2-C₆F₄ (b), (Z)-CH=CH (c), CH₂CH₂ (d)], have been synthesized from reaction of tricyclohexyltin hydroxide with cyclic dicarboxylic anhydrides under microwave irradiation in 1 : 1 and 2 : 1 M ratio, respectively, and characterized by elemental analysis, IR and NMR (¹H, ¹³C, and ¹¹⁹Sn) spectra. Crystal structures of 1a–1c and 2d are determined by X-ray single crystal diffraction. The carboxylate in each compound is monodentate to tin. Compounds 1a and 1c possess a trans-C₃SnO₂ trigonal bipyramidal geometry with axial positions occupied by carboxylate and carbonyl oxygen of carboxylate of an adjacent molecule forming a one-dimensional chain. Compound 1b is tetrahedral and forms R ₂ ²(8) hydrogen-bonded dimers by pairs of intermolecular O–HO hydrogen bonds between two carboxylic acid groups. Compound 2d is dinuclear with tin possessing distorted tetrahedral geometry; a trimer supramolecular structure is formed by weak intermolecular SnO interactions. The compounds have potent in vitro cytotoxic activity against two human tumor cell lines, A549 and HeLa.

Keywords:

• Organotin complex
• Tricyclohexyltin(IV) carboxylate
• Cytotoxic activity
• Crystal structure

Acknowledgments

This work was supported by Shandong Provincial Natural Science Foundation, China (ZR2010BL012) and the National Natural Science Foundation of China (20931001; 21173126).