Antileishmanial and Antitoxoplasmal Activities of Acetone-Derived Monoketone Curcuminoids

Background/Objectives: Leishmaniasis and toxoplasmosis are zoonoses that cause millions of deaths annually. This study aimed to synthesize and investigate the in vitro antileishmanial and antitoxoplasmal activity of eight ace-tone-derived monoketone curcuminoids (MKCs). Methods: MKCs 1-8 were synthesized using a base-catalyzed Claisen-Schmidt condensation. These compounds were evaluated against Leishmania major promastigotes and amastigotes, and Toxoplasma gondii. Results: Compounds 4 ((1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4-dien-3-one) and 5 ((1E,4E)-1,5-bis(4-bromophenyl)penta-1,4-dien-3-one) were very active against L. major promastigotes (IC50 of 6.9 and 6.6 µM, respectively) and amastigotes (IC50 of 21.4 and 30.3 µM, respectively). Compound 4 was also active against T. gondii (IC50 = 15.8 µM). Docking studies revealed that compounds 4 and 5 has a high affinity for the L. major target (PDB ID: 1E92). Conclusions: The results of this study indicated that the presence of halogen (chlorine or bromine) atoms boosts the antileishmanial and antitoxoplasmal activity of acetone-derived monoketone curcuminoids. Furthermore, ADMET predictions indicated that compounds 4 and 5 meets the drug-likeness criteria without violating any Lipinski, Veger, or Egan’s rules