[Synthesis and biological activities of 2,4-diamino-5-fluoro-6-substituted benzylamino quinazolines].

The title compounds were synthesized by condensation of 5-fluoro- 2, 4, 6-triaminoquinazoline (6a) with various substituted benzaldehydes to produce the corresponding Schiff bases, followed by reduction. II and III were obtained by formylation and nitrosation of I, respectively, IV were obtained by reduction of II. Primary screening for suppressive therapeutic effects against P. berghei in mice showed that six of the twenty-two compounds produced 100% suppression when administered orally at a dose of 1 mg.kg-1. All compounds exhibited potent activity against L1210 cell in vitro. Among them I4 was more active than MTX. A number of compounds showed moderate activities against Diplococcus pneumoniae in vitro tests.