Design and synthesis of 3,5-dialkylamino substituted 8H,10H-3(R),5(R),15b(S)-2,3,6,7-tetrahydro-1,5,3-dioxazepino[3,2-c]indolo[3,2-g]pteridine-7-ones

3,5-Dialkylamino substituted 8H,10H,15b(S)-2,3,6,7-tetrahydro-1,5,3-dioxazepino[3,2-c]indolo[3,2-g]pteridine-7-one derivatives 6a-6e were synthesized as potential anticancer agents. Preliminary results showed that they were active as inhibitors of the growth of murine leukemia L1210 cells in vitro with IC50 -values of 4 to 24 μM.