Stability constants of potent cytotoxic copper(II) complexes with furan semicarbazones in ethanolic solutions

Potent cytotoxic copper(II) complexes of furannic semicarbazones were studi ed in ethanolic solutions at 25 degrees C. The four ligands used were synth esized in our laboratory, i.e. 2-furfural semicarbazone (FSC), 5-methyl 2-f urfural semicarbazone: (MFSC), 2-furfural 4-phenyl semicarbazone (FPSC) and 3-(2-furyl) prop-2-enal semicarbazone (FASC). The mathematical analysis wa s carried out with a recent computer program smite which indicated the form ation of one: metal-ligand complex in each case and the logarithm of their stability constants are: log beta = 2.02, 3.84, 4.58 and 4.52 for ligands F SC, MFSC, FASC and FPSC, respectively. A relation between stability and mol ecular weight of the ligands is proposed which may prove to be interesting as these complexes are being investigated for their cytotoxic activities. ( C) 2000 Elsevier Science S.A. All rights reserved.