A rapid stereocontrolled synthesis of the 3a-hydroxy-pyrrolo[2,3-b]indole skeleton, a building block for 10b-hydroxy-pyrazino[1 ',2 ': 1,5]pyrrolo[2,3-b]indole-1,4-diones

A two-step selenocyclisation-oxidative deselenation sequence was used to establish the 3a-hydroxy-pyrrolo-[2,3-b]indole core; these tricycles were used as effective precursors to 10b-hydroxy-pyrazino[1',2' : 1,5]pyrrolo-[2,3-b]indole-1,4-diones.