112-119A series of new furoxan derivatives of praziquantel have been synthesized and evaluated for antischistosomal activity. The newly synthesized hybrid compounds have structural modifications at amide and aromatic rings and thus offer broad structure-activity variations. All the compounds have been tested against adult as well as immature Schistosoma mansoni. Compounds 15 and 18 show moderate activity against adult schistosomes. On immature worms, only compound 15 shows substantial activity whereas the standard drug PZQ is practically inactive at this stage