Synthesis and Anthelmintic Evaluation of Novel Valerolactam- Benzimidazole Hybrids

Some novel valerolactam derivatives of 5(6)-substituted-(1H-benzimidazol-2-yl-amine) were constructed based on the union of two structural domains with anthelmintic activity. The tested hybrid compounds 7-9 exhibited greater activity using the Nippostrongylus brasiliensis physiology-based in vitro bioassay in comparison to commercial anthelmintic benzimidazoles. Moreover, the improved physicochemical properties of hybrid compounds compared with valerolactam domain allowed the penetration of parasite barriers, concurrently with an increased intraparasitary bioavailability.