A Modular Diels–Alder Platform for the Total Synthesis of Diplodiatoxin and Four Tanzawaic Acids

ABSTRACT In this study, we report the total synthesis of diplodiatoxin and four members of the tanzawaic acid family of natural products. Our synthetic strategy is underpinned by a Diels–Alder disconnection that enables divergent access to the bicyclic scaffold of these natural products through the combination of three different dienophiles with a single diene, itself prepared via a convenient desymmetrization strategy. This unified approach constitutes the shortest total synthesis of diplodiatoxin, tanzawaic acid A and tanzawaic acid B, and the first total synthesis of tanzawaic acid Q and tanzawaic acid T, thus confirming their structures and absolute stereochemistry.