Preparation and pharmacochemical evaluation of mixed ligand copper(II) complexes with triethanolamine and thiophenyl-2 saturated carboxylic acids

The dinuclear complex [Cu-2(L-1)(2)(H(2)tea)(2)] (1) as well as the linear trinuclear complexes [Cu-3(L-1)(4)(H(2)tea)(2)] (2), [Cu-3(L-2)(4)(H(2)tea)(2)] (3) and [Cu-3(L-1)(2)(H(2)tea)(2)(NO3)(2)] (4) where L-1 = 2-thiophene carboxylato, L-2 = 2-thiophene acetato and H(2)tea = the single deprotonated form of triethanolamine have been prepared and pharmacochemically studied. The crystal structure of 1 is also reported. In vitro antioxidant activity of free ligands and their respective copper complexes includes: a) interaction with 1,1-diphenyl-2-picrylhydrazyl stable free radical, b) the HO center dot mediated oxidation of DMSO, c) scavenging of superoxide anion radicals, d) inhibition of lipid peroxidation and e) soybean lipoxygenase inhibition. The results indicate selectivity of the complexes to different free radicals as a consequence of their physichochemical features. The majority of the complexes 1, 2, 3, 4 effectively inhibit lipid peroxidation. The trinuclear complex 3 is by far the most active with IC50 = 10 mu M, within the set, followed by complexes 1 and 2. The complexes were evaluated for their efficacy as anticancer agents against different cancer and normal human cell lines. Results showed that, these compounds mediate a moderate cytotoxic response to normal and cancer cell lines tested and induce cell cycle arrest in G2/M phase of the cell cycle. Flow cytometric analysis suggested that the tested compounds can induce apoptosis. (C) 2011 Elsevier Inc. All rights reserved.