Synthesis of selected 3-substituted-pyrimido[5,4-e]1,2,4-triazine-5,7-diamines as potential folate antagonists

3-(Anilinomethy1) 3-(arylthio)methy1]pyrimido5,4-e]-1,2,4-triazine-5,7-diamines were prepared by ring closure of 6-hydrazino-4-(phenylmethy1)thio]-2.5-pyrimidinediamine. these nonclassical analogs of known potent dihydrofolate reductase inhibitors were inactive against malarial infections in mice and L1210 leukemia in vitro.