Antioxidant Versus Cytotoxic Properties of Hydroxycinnamic Acid Derivatives – A New Paradigm in Phenolic Research

Trihydroxycinnamic derivatives were synthesized and evaluated for their antioxidant and cytotoxic activities. The ester derivatives exhibited a higher radical-scavenging activity, when liposomes were used as target systems, a fact which may be related to their lipophilicity and conformational preferences. These compounds were found to display significant growth inhibition and cytotoxic effects towards a human cervix adenocarcinoma cell line (HeLa). The partition coefficients presently obtained for the trihydroxycinnamic derivatives correlate well both with their structural characteristics and with their antioxidant/cytotoxic activities. A positive structure-activity-property relationship between cytotoxic and antioxidant activities, which is intrinsically related with physico-chemical and conformational properties, is anticipated, as a noteworthy study that must be done for phenolic systems. As damage events are frequently correlated with oxidative stress, the prevalence of both properties in a single compound could be beneficial in terms of rationale preventive or therapeutic purposes.