Abstract
Copper(I) complexes of thioureas having the general formulae [CuLnBr] and [CuLn]Br [where, n = 1 - 4 and L = thiourea (Tu), N-methylthiourea (Metu), N-ethylthiourea (Ettu), N,N'-dipropylthiourea (Dprtu), N,N'-dibutylthiourea (Dbtu) or N,N'-diphenylthiourea (Dphtu)] were prepared and characterized by elemental analysis, IR, and NMR (H-1 and C-13) spectroscopy. The crystal structure of one of them, [Cu(Metu)(4)]Br (1), was determined by X-ray crystallography. The X-ray structure of 1 describes a tetrahedral geometry around copper(I) with all Metu ligands binding through sulfur atoms. An upfield shift in the C-13 NMR and downfield shift in the H-1 NMR spectra are consistent with the thione coordination to copper(I). Antimicrobial activities of the complexes were evaluated by the minimum inhibitory concentration method. The results showed that only [Cu(Ettu)(3)Br] was effective in inhibiting the growth of all the tested organisms (gram-positive, gram-negative bacteria, and Candida sp.), while the other complexes were not effective against all the organisms.