Enantioselective Total Synthesis of (+)-Pepluanol A.Herein, we report an enantioselective and convergent total synthesis of (+)-pepluanol A, a structurally intriguing Euphorbia diterpenoid natural product featuring a 5/6/7/3-fused tetracyclic skeleton, from known building blocks in 11 steps.  The successful strategy relies on a phenyl selenide-mediated Morita-Baylis-Hillman type reaction as a connective step, forging the precursor for the key intramolecular Diels-Alder reaction to construct the congested 5/6/7-tricyclic framework.  A diastereoconvergent cascade starting with an acid-induced removal of the C1-MOM protecting group followed by a retro-aldol/aldol reaction resulted in the formation of a single diastereomer.  This stereoconvergency allowed for the successful substrate-controlled diastereoselective cyclopropanation of an advanced intermediate to establish the full carboskeleton of (+)-pepluanol A (1).
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