Total Synthesis of Oridamycins A and B.

The total synthesis of both oridamycin A and oridamycin B was accomplished starting from a common synthetic intermediate readily prepared from geranyl acetate. The sequence utilizes an oxidative radical cyclization to construct the trans-decalin ring system, setting three of four contiguous stereocenters in one operation. The carbazole nucleus was forged through a one-pot process entailing acid-promoted dehydration followed by 6π-electrocyclization/aromatization.