Fukuyamas Total Synthesis of the CP-Molecules

One can only hope that the instructive nature of the challenges confronted in this synthesis will encourage chemists in the future to be more willing to share such unique moments of their synthetic endeavors with the rest of the community. Not only would such an approach effectively convey the vitality of this field of research to the next generation of synthetic practitioners, but it would also ensure the more rapid extension of basic knowledge in chemical synthesis in directions that, for the present, can barely be imagined. 

With this essential operation implemented, the crude Diels—Alder product (119) was then subjected to reaction with the lithium anion derived from allyl mercaptoacetate, an event that provided 120 in 53% overall yield from 117. Seeking next to create the maleic anhydride moiety, treatment of this product (120) with DBU in THF at ambient temperature then resulted in an intramolecular aldol reaction that furnished 121 in 93% yield as a single stereoisomer. Following decarboxylation at C-31 and dehydration of the alcohol group at C-11 to generate a thiobutenolide, a few 

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