A novel cytotoxic ternary copper(II) complex of 1,10-phenanthroline and L-threonine with DNA nuclease activity

A novel ternary copper(II) complex, [Cu(phen)(L-Thr)(H2O)1(ClO4) (phen = 1,10-phenanthroline, L-Thr = L-threonine), has been synthesized and structurally characterized. The complex crystallized in a triclinic system with space group P $(1) over bar $, a = 7.526(15) Angstrom, b = 11.651(2) Angstrom, c = 12.127(2) Angstrom, alpha = 115.41(3)degrees, beta = 102.34(3)degrees and 7 = 91.33(3)degrees. The copper(II) center is situated in a distorted square-pyramidal geometry. At a concentration of 10(-6) mol L-1, the complex exhibited potent cytotoxic effects against human leukemia cell line HL-60 and human stomach cancer cell line SGC-7901 with inhibition rates of over 90% however, less pronounced effects were observed for human liver carcinoma cell line BEL-7402 and human non-small-cell lung cancer cell line A-549. The complex was shown to bind DNA by intercalation and cleave pBR322 DNA in the presence of ascorbate. (C) 2004 Elsevier Inc. All rights reserved.