Initial reaction of 3-ethyoxy-2-oxobutyraldehyde bis(thiosemicarbazonato) copper(II) with Ehrlich ascites tumor cells.

The antineoplastic agent, 3-ethoxy-2-oxobutyraldehyde bis(thiosemicarbazonato) copper(II), undergoes a pseudo-first-order decomposition in the presence of viable Ehrlich ascites tumor cells. Physical and chemical methods show that the copper is reduced in this process, that thiols are involved in the reaction, and that the thiosemicarbazone ligand is displaced from the copper ion. The widespread distribution of the cell-bound copper suggests several modes of cytotoxicity.