Synthesis and biological activities of NB-506 analogues: Effects of the positions of two hydroxyl groups at the indole rings.

Abstract In the course of a study of 6- N -amino-substituted analogues of NB-506 ( 1 ), a more potent anticancer drug, J-109,404 ( 2 ), in which the formyl group of NB-506 was replaced with a 1,3-dihydroxypropane group, was reported. A study of further modification in the positions of two hydroxyl groups at the indole rings of 2 resulted in the discovery of a 2,10-dihydroxy analogue, J-107,088 ( 3 ), which is a promising anticancer agent with a broader therapeutic window than J-109,404. A study of further modification in the positions of two hydroxyl groups at the indole rings of J-109,404 ( 2 ) resulted in the discovery of a 2,10-dihydroxy analogue, J-107,088 ( 3 ), which is a promising anticancer agent with a broader therapeutic window than J-109,404.