In vitro evaluation of antitrypanosomal activity and molecular docking of benzoylthioureas.

A series of sixteen benzoylthioureas derivatives were initially evaluated in vitro against the epimastigote form of Trypanosoma cruzi. All of the tested compounds inhibited the growth of this form of the parasite, and due to the promising anti-epimastigote activity from three of these compounds, they were also assayed against the trypomastigote and amastigote forms. ADMET-Tox in silico predictions and molecular docking studies with two main enzymatic targets (cruzain and CYP-51) were performed for the three compounds with the highest activity. The docking studies showed that these compounds can interact with the active site of cruzain by hydrogen bonds and can be coordinated with Fe-heme through the carbonyl oxygen atom of the CYP51. These findings can be considered an important starting point for the proposal of the benzoylthioureas as potent, selective, and multi-target antitrypanosomal agents.

Benzoylthioureas: Design, Synthesis and Antimycobacterial Evaluation.

BACKGROUND: New drugs and strategies to treat tuberculosis (TB) are urgently needed. In this context, thiourea derivatives have a wide range of biological activities, including anti-TB. This fact can be illustrated with the structure of isoxyl, an old anti-TB drug, which has a thiourea as a pharmacophore group. OBJECTIVE: The aim of this study is to describe the synthesis and the antimycobacterial activity of fifty-nine benzoylthioureas derivatives. METHODS: Benzoylthiourea derivatives have been synthesized and evaluated for their activity against Mycobacterium tuberculosis using the MABA assay. After that, a structure-activity relationship study of this series of compounds has been performed. RESULTS AND DISCUSSION: Nineteen compounds exhibited antimycobacterial activity between 423.1 and 9.6 µM. In general, we observed that the presence of bromine, chlorine and t-Bu group at the para-position in benzene ring plays an important role in the antitubercular activity of Series A. These substituents were fixed at this position in benzene ring and other groups such as Cl, Br, NO2 and OMe were introduced in the benzoyl ring, leading to the derivatives of Series B. In general, Series B was less cytotoxic than Series A, which indicates that the presence of a substituent at benzoyl ring contributes to an improvement in both antimycobacterial activity and toxicity profiles. CONCLUSION: Compound 4c could be considered a good prototype to be submitted to further structural modifications in the search for new anti-TB drugs, since it is 1.8 times more active than the first line anti-TB drug ethambutol and 0.65 times less active than isoxyl.