Selenium compounds are pivotal in medicinal chemistry for their antitumoral and
antioxidant properties. Forty seven acylselenoureas have been designed and synthesized following
a fragment-based approach. Different scaffolds, including carbo- and hetero-cycles, along with
mono- and bi-cyclic moieties, have been linked to the selenium containing skeleton. The doseand time-dependent radical scavenging activity for all of the compounds were assessed using the
in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,20
-azino-bis(3-ethylbenzthiazoline-6-sulfonic
acid) (ABTS) assays. Some of them showed a greater radical scavenging capacity at low doses and
shorter times than ascorbic acid. Therefore, four compounds were evaluated to test their protective
effects against H2O2-induced oxidative stress. One derivative protected cells against H2O2-induced
damage, increasing cell survival by up to 3.6-fold. Additionally, in vitro cytotoxic activity of all
compounds was screened against several cancer cells. Eight compounds were selected to determine
their half maximal inhibitory concentration (IC50) values towards breast and lung cancer cells, along
with their selectivity indexes. The breast cancer cells turned out to be much more sensitive than the
lung. Two compounds (5d and 10a) stood out with IC50 values between 4.2 µM and 8.0 µM towards
MCF-7 and T47D cells, with selectivity indexes greater than 22.9. In addition, compound 10b exhibited
dual antioxidant and cytotoxic activities. Although further evidence is needed, the acylselenourea
scaffold could be a feasible frame to develop new dual agents