LAUSR

Trypanosoma cruzi is the causative pathogen of Chagas disease and the main culprit for cardiac-related mortality in Latin-America triggered by an infective agent. Uncapable of synthesizing purines de novo, this parasite depends on acquisition and processing of host-derived purines, making purine (nucleoside) analogues a potential source of antitrypanosomal agents. In this respect, hitherto 7-deazaadenosine (tubercidin) analogues attracted most attention. Here, we investigated analogues with an additional nitrogen (N1) removed. Structure-activity relationship investigation showed that C7 modification afforded analogues with potent antitrypanosomal activity. Halogens and small, linear carbon-based substituents were preferred. Compound 11 proved most potent in vitro, showed full suppression of parasitemia in a mouse model of acute infection and elicited 100 % animal survival after oral dosing at 25 mg/kg b.i.d. for five and fifteen days. Cyclophosphamide-induced immunosuppression led to recrudescence. Washout experiments demonstrated a lack of complete clearance of infected cell cultures, potentially explaining the in vivo results.