Abstract

A series of 3-(3-Arylpropenoyl)imidazopyridine (5a to z) was synthesized by crotonization reaction of 2-methyl-3-acetylimidazopyridine with arylaldehyde derivatives. Structuraldetermination of these new chalcones was done by ¹H nuclear magnetic resonance (NMR),¹³C NMR and electrospray ionization (ESI) mass spectroscopy. All compounds have beenevaluated in vitro for their anthelmintic activities against Haemonchus contortus. Compounds5n, 5s, 5t and 5w showed a great nematicidal activity (LC₁₀₀) ranging between 0.0005 and0.002 µg/ml. The activity of these four chalcones was equivalent to that of fenbendazole andivermectin which were reference anthelmintic drugs. This study has shown that imidazopyridine-chalcone derivatives are promising candidates for the development of new anthelmintic agents.

Key words: Haemonchus contortus, imidazopyridine, chalcone, nematicidal activity.