The electrochemical behavior of four dialkyl esters (methyl, ethyl, n-propyl and n-butyl) of (S,S)-alpha,alpha'-(1,2-ethanediyldiimino)-bis[cyclohexanepropanoic acid] with moderate antitumor activity has been studied by cyclic voltammetry. I-E curves recorded at boron-doped diamond electrode in -2.00 < E-p < 0.00 V range show a single oxidative peak located in the -0.95 < E-p,E-a < -0.52 V region in a form of one-electron wave. The electrochemical processes appear to be irreversible for all compounds except for the compound with methyl substituent which demonstrates well-defined reversible electron transfer. Derivatives with bulkier moieties are easier to oxidize. For all investigated compounds an amine-centered redox process is dominant. Further investigation indicates that electrochemical reaction is diffusion controlled, chemically irreversible process. The results are discussed in terms of linking their electrochemical activity to antitumor effect. (C) 2018 The Electrochemical Society.