Sirawaraporn et al.8 reported some 5-benzyl-2,4-diaminopyrimidines as selective inhibitors of leishmanial DHFR. These compounds also showed some in vitro activity against Leishmania donovaniamastigotes. The most active and selective compound against the parasiteenzyme was the 30-octyloxy derivative 1 (n=7) (Fig. 1). We then conducted an extensive structure activity study with the 30-series of compounds and extended the study to include T. brucei and T. Cruzi.4