In vitro anti-trypanosomal potential of kaurane and pimarane semi-synthetic derivatives.

As part of the search for anti-trypanosomal agents, this work presents the production of sixteen derivatives. All of them were obtained from two natural diterpenes, one with kaurane skeleton (ent-kaurenoic acid) and other with a pimarane skeleton (ent-pimaradienoic acid). Then, the eighteen compounds were assayed against epimastigote form of Trypanosoma cruzi, with the derivatives showing increase of activity in relation to their precursors. Moreover, the most active derivative presented an IC50 <12.5 µM (estimated 0.8 µM), lower than Benznidazole (IC50 = 9.8 µM), used as control. The esterification of acid diterpenes showed to be an interesting way in the search for anti-trypanosomal agents.