Antischistosomal activity of N,N′-arylurea analogs against Schistosoma japonicum

Abstract Although the antischistosomal activities of N , N′ -arylurea analogs were reported, systematic structure–activity relationships have not been conducted. In this Letter, we reported the design, synthesis and evaluation of 45 N , N ′ - arylurea analogs. Among these prepared compounds, 13 compounds were urea linker modified and 32 were N , N ′-arylurea derivatives. The activity evaluation revealed 12 analogs exhibited IC 50 values lower than 22.6 μM, and 7 of them had IC 50 less than 10 μM against the juvenile Schistosoma japonicum in vitro. Their worm killing potency was even higher against adult worm. Unfortunately, low to moderate worm burden reduction of 0–33.4% was recorded after administration of a single oral dose of 200 mg/kg or 400 mg/kg to mice harboring S. japonicum .