The protozoan toxin climacostol and its derivatives: cytotoxicity studies on 10 species of free-living ciliates

摘要

Climacostol (5-(Z)-non-2-enyl-benzene-1,3-diol) is a natural toxin isolated from the freshwater ciliated protozoanClimacostomum virens and belongs to resorcinolic lipids, a group of compounds that show antimicrobial, antiparasitic, andanticancer activities. We investigated the cytotoxic activity of the chemically synthesized toxin and its alkyl and alkynylderivatives on C. virens and nine other common species of free-living freshwater ciliates. Our results show that the cytotoxicpotency of climacostol can be modulated by the substitution of the double bond present in the aliphatic chain of the toxinwith a single or a triple one that was previously obtained during the synthesis of the unsaturated and saturated derivativesof the parent molecule. We demonstrated that the cytotoxicity level of the molecules considered in this study appears to beinversely correlated to the unsaturation level of their aliphatic chains, and that the potency of their action is also relatedto the target organism.