Iron chelation and inhibition of metallopeptidases mediate anti-Trichomonas vaginalis activity by a novel 8-hydroxyquinoline derivative.

Trichomoniasis is a neglected parasitic infection, with no oral therapeutic alternatives to overcome the pitfalls of currently approved drugs. In this context, the search for new anti-Trichomonas vaginalis drugs is imperative. Here we report the selective anti-T. vaginalis activity of a substituted 8-hydroxyquinoline-5-sulfonamide derivative. Six different derivatives were evaluated for anti-T. vaginalis. In vitro and in vivo toxicity methods, association with metal ions, and investigation on the mechanism of action were performed with the most active derivative, PH 152. Cytotoxicity assays showed selectivity for the parasite and the low toxicity was confirmed in G. mellonella larvae model. The mode of action is related to iron chelation by disrupting Fe-S clusters-dependent enzyme activities in the parasite. Proteomic analysis indicated inhibition of metallopeptidases related to T. vaginalis virulence mechanisms and metabolic pathways. PH 152 presented selective trichomonacidal activity through multitarget action.

Limonene and Perillyl Alcohol Derivatives: Synthesis and Anticancer Activity.

Limonene and perillyl alcohol are natural monoterpenes that have attracted the attention of medicinal chemists due to their promising anticancer activities. Considering this, both compounds were explored as scaffolds to obtain various derivatives with anticancer activity. In this review, the data are organized for the first time, with a focus on the synthetic methods and strategies to obtain the derivatives throughout the period from 2000 to 2020. A brief discussion regarding the structure and activity relationships of the most active derivatives, stereoisomers, and their mechanisms of action is presented. Among the active compounds, a series of limonenes with thiosemicarbazone groups and perillyl alcohol hybrids with glycosides or drugs are illustrated. Taking all of this into account, this review may help researchers develop new promising anticancer candidates based on the structures of limonene and perillyl alcohol.