Abstract
The reactions of ZnCl2 and cysteamine hydrochloride (Cym-H center dot HCl) in the presence of diamines; 1,3-diaminopropane (dap) and tetramethylethylenediamine (tmen) yielded a Zn-cysteaminate complex, [Zn(4)Cym(4)Cl(4)] (1). In the similar reaction with cis-1,2-diaminocyclohxane (dach), a diamine complex, [Zn(dach)Cl-2] (2) was obtained. The compounds, 1 and 2 were characterized by elemental analysis, IR and NMR (H-1 and C-13) spectroscopy. The crystal structure of 1 was determined by X-ray crystallography. The structure of 1 shows that the complex exists in the form of a tetranuclear molecule in which zinc atoms are bridged by S atoms of Cym forming an eight-membered ring. The complex consists of two crystallographically independent Zn(II) ions. Zn1 and symmetry related ion are coordinated with two sulfur atoms and two nitrogen atoms of Cym, while Zn2 and symmetry related ion exhibit a ZnS2Cl2 setup. In both coordination environments zinc atom adopts a distorted tetrahedral geometry. Antimicrobial activities of the complex 1 were evaluated by minimum inhibitory concentration and the results showed that the complex exhibited remarkable activities against gram-negative bacteria (E. coli, P. aeruginosa) and yeasts (C. albicans, S. cerevisiae).