Collective Total Synthesis of Aculeatin A, B, D, E, and F

A collective convergent approach for the enantioselective total synthesis of aculeatins A, B, D, E, and F is presented, featuring [3 + 2]-cycloaddition, iron-mediated reductive N–O bond cleavage, and cascade spirocyclization. Moreover, this short six-step strategy is supplemented in synthesizing unnatural analogs of aculeatins such as 6-epi-aculeatin D, 6-epi-aculeatin E, and 6-epi-aculeatin F.