Antileishmanial and antimalarial activities of synthetic marine endoperoxides

Synthetic samples and analogs of marine endoperoxides derived from mycaperoxides and plakortides were screened for their antileishmanial and antimalarial activities. It was found that these compounds exhibited significant activity against both parasites in the micromolar range. However, mycaperoxide analogs also exhibited high cytotoxicity against both cancer and healthy mammalian cell lines in the micromolar range. By contrast, ethyl plakortide Z showed minimal to no cytotoxic activity, leading to interesting potential against P. falciparum (IC50 = 2.90 ± 1.13 µM, SI > 62) and L. major (IC50 = 16.87 ± 2.04 µM, SI > 5.9). The specific cytotoxicities of mycaperoxides might be attributed to the carboxylic acid functional group, which is absent in ethyl plakortide Z.