Invitro and Invivo Activity of Benzimidazole derivatives against Trypanosoma Congolense, design and synthesis

African animal trypanosomosis (AAT) is caused by the tsetse fly-transmitted protozoans congolense were and leads to huge agricultural losses throughout sub-Saharan Africa. The current chemotherapy of animaltrypanosomosis relies on certain drugs (suramin, pentamidine, melarsoprol, eflorinithine, nifurtimox, Diminazene), five of which developed more than 30 years ago. With increasing reports of drug-resistant populations, new benzimidazoles should be investigated as potential candidates to combat trypanosomal diseases. In the present study, 34compounds of benzimidazole derivatives were synthesized by reacting Schiff bases with benzyl chloride, benzene sulphonyl chloride and potassium carbonate in acetone. The Schiff bases were synthesized by treating various aromatic aldehydes with O-phenyldiamine. From invitro test, 22 products were tested against T. congolense, six compounds (4A, 2B, 4-OGN, 4-OGS, OGN, and 3A) have sown promising efficacy (up to 100% parasite clearance from the test blood) some at 20mg/ml and others at both 20mg/ml and 10mg/ml. Some have shown very early response in the first 5 minutes of incubation while others have shown good efficacy between 10 and 15 minutes of incubation. From the invivo test, compared to the non-infected negative control and the commercial drug (diminazen aceturate) treated as a positive control; the test product was not shown promising activity in terms of both reducing blood parasitemia and preventing mice mortality. In line with lack of activity on parasitemia and mice survival, PCV measurement also shows no contribution of the test products on improvement or maintenance of PCV. Characterization of the compounds was achieved using spectroscopic techniques including IR, UV-Vis and 1D and 2D NMR.