Development of novel valerolactam-benzimidazole hybrids anthelmintic derivatives: Diffusion and biotransformation studies in helminth parasites.

•Further studies of novel benzimidazole bioactive hybrids are presented.•Diffusion in H. contortus (susceptible/from sheep farms) and M. vogae is presented.•Sulphoxidation drug metabolism was measured in both target parasites.•Oxidation was more relevant in H. contortus parasites from sheep farms.•New hybrid compound 10 was not oxidized and showed a high diffusion rate.