Efficient synthesis of jusbetonin, an indolo[3,2-b]quinoline glycoside, and its derivatives.

Jusbetonin, an indolo[3,2-b]quinoline alkaloid glycoside originally isolated from Justicia betonica, and its derivatives were synthesized. The key steps in the synthetic strategy were the construction of indolo[3,2-b]quinoline skeleton and efficient coupling with the saccharides, in which the alpha-D-glycopyranosyl bromides were shown to be effective donors. Primary screening showed that all synthesized compounds possessed moderate proliferation inhibitory activity.