Copaifera diterpenoids showed excellent docking to L. mexicana pyruvate kinase (average Edock = −103.4 kJ/mol), much better than the normal substrate, phosphoenolpyruvate (Edock = −59.8 kJ/mol). Docking energies with T. cruzi pyruvate kinase were not as impressive (average −80.3 kJ/mol), but still better than phosphoenolpyruvate (Edock = −48.6 kJ/mol) and comparable to the TcPYK inhibitor, ponceau S (Edock = −83.6 kJ/mol). Parasite pyruvate kinases can be expected to be target proteins for Copaifera diterpenoids.