Tin(IV) complexes of pyrrolidinedithiocarbamate: synthesis, characterisation and antifungal activity

The reaction of ammonium pyrrolidinedithiocarbamate, [NH 4{S 2CN(CH 2) 4}], with SnCl 2, [Sn(C 6H 5) 2Cl 2], [Sn(C 6H 5) 3Cl], [Sn(C 4H 9) 2Cl 2] and [Sn(C 6H 11) 3Cl] produced in good yield the compounds [Sn{S 2CN(CH 2) 4} 2Cl 2] (1), [Sn{S 2CN(CH 2) 4} 2Ph 2] (2), [Sn{S 2CN(CH 2) 4}Ph 3] (3), [Sn{S 2CN(CH 2) 4} 2 n-Bu 2] (4) and [Sn{S 2CN(CH 2) 4}Cy 3] (5). The complexes were characterised by infrared, multinuclear NMR ( 1H, 13C{ 1H} and 119Sn{ 1H}) and 119Sn Mössbauer spectroscopies. In addition, the crystal structure of 4 was determined by X-ray crystallography. The in vitro antifungal activity of the tin(IV) complexes as well of the ligand was performed on human pathogenic fungi, Candida albicans, in concentrations of 0.025; 0.050; 0.100; 0.200; 0.400; 0.800; 1.600 and 3.200 mM. The microorganism presented resistance to the dithiocarbamate ligand and all tin(IV) complexes tested were actives. The highest activity was found for compounds 1 and 4.