The syntheses, structural elucidation based on NMR spectroscopy and X-ray analysis of 8 as well as antitumor activities of novel 2, 4-diamino-1, 3, 5-triazine derivatives 5 and 7–22 are described. Screenings performed at NCI showed that most derivatives possessed a moderate to strong growth inhibition activity on various tumor panel cell lines between 0.148 and 56.2 μM concentrations. 2-Amino-6-bromomethyl-4-(3, 5, 5-trimethyl-2-pyrazoline)-1, ...