alkylation occurred primarily on N-5 (1:0.8:0.8) or N-6 (1:1.5:1.5) leading to the isolation of 14a or 14b as a major product. Accordingly, major product 15a (2/(MeO)2SO2/K2CO3=1:2:2) or 15b (1:1:1), respectively, was obtained by alkylation of 12 while 16a (13/(MeO)2SO2/K2CO3=1:2:2) or 16b (1:1:1), respectively, was obtained by alkylation of 13. The in vitro anticancer assay indicated 5-methylated derivatives