The effect of novel aromatic heterocycle substituted aminamidine derivatives on Necator americanus.

ABSTRACT

BACKGROUND: The efficacy of current drugs against hookworms at a single dose is highly variable across regions, age groups and infection intensity. Extensive and repeated use of these drugs also leads to potential drug resistance. Therefore, novel drugs are required for sustained disease control. OBJECTIVES: Novel aromatic heterocycle substituted aminamidine derivatives (AADs) were synthesized based on tribendimine (TBD), and their in vivo potency against Necator americanus was tested. METHODS: The efficacy of the AADs was tested in male hamsters. Oral and IV pharmacokinetic parameters were determined in male Sprague-Dawley rats. The proteomic profiles of N. americanus samples treated with AADs were compared using tandem mass tag-based quantitative proteomic analyses. RESULTS: Most AADs exhibited better anthelmintic activity than TBD at a single oral dose. Compound 3c exhibited improved solubility (>50×), and the curative dose was as low as 25 mg/kg. Similar to TBD, 3c was rapidly metabolized after oral administration and transformed into p-(1-dimethylamino ethylimino)aniline (dADT), an active metabolite against intestinal nematodes. dADT from 3c had better pharmacokinetic profiles than that from TBD and achieved an oral bioavailability of 99.5%. Compound 3c possessed rapid anthelmintic activity, clearing all worms within 24 h after an oral dose of 50 mg/kg. Quantitative proteomic analysis indicated that it might be related to ATP metabolism and cuticle protein synthesis. CONCLUSIONS: Compound 3c is a novel and promising compound against N. americanus in vivo.