Synthesis of chalcone derivatives by Claisen-Schmidt condensation and in vitro analyses of their antiprotozoal activities

• Published in: Natural product research 2024-04, Vol.38 (8), p.1326-1333
• Main Authors: Souza, Gabriella B., Santos, Tamiris A. C., Silva, Amanda P. S., Barreiros, André L. B. S, Nardelli, Victória Brandão, Siqueira, Ingrid B., Dolabella, Silvio S., Costa, Emmanoel.V., Alves, Péricles B., Scher, Ricardo, Fernandes, Roberta P. M.
• Format: Article
• Language: English
• Subjects: Acanthamoeba polyphaga; Antiprotozoal activity; Antiprotozoal Agents - chemistry; Antiprotozoal Agents - pharmacology; Chalcone; Chalcones - pharmacology; Chemical synthesis; Claisen-Schmidt reaction; Leishmania amazonensis; NMR; Nuclear magnetic resonance; Phytomonas serpens; Structure-Activity Relationship
• ISSN: 1478-6419; 1478-6427
• DOI: 10.1080/14786419.2022.2140337

Chalcone is a molecule with known biological activities. Based on this, a series of chalcone derivatives bearing methyl, phenyl or furanyl substituents at different positions of A and B rings were synthesised, characterised, and evaluated regarding antiprotozoal activity. Molecules were synthesised via base catalyzed Claisen-Schmidt condensation and characterised by IR and NMR spectral data. Antiprotozoal activity against Phytomonas serpens, Leishmania amazonensis and Acanthamoeba polyphaga was performed. All compounds inhibited more than 50% of the growth of P. serpens while five had this effect on L. amazonensis and all of them no more than 35% of inhibition on A. polyphaga. Remarkably interesting antiprotozoal effects were recorded with compound 5, with IC 50 of 1.59 µM for P. serpens and 11.49 µM for L. amazonensis. The addition of a naphthyl group to the B ring can be postulated to be the cause of the 10 times increase observed in its trypanocidal activity.