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Total Synthesis of UCS1025A via Tandem Carbonylative Stille Cross Coupling and Diels‐Alder Reaction †
Comprehensive Summary We report an efficient and convergent strategy for the total synthesis of UCS1025A and its diastereomer tetra‐epi‐UCS1025A. UCS1025A is a representative member of the naturally occurring pyrrolizidinone polyketides, from which members with potent antibacterial, antifungal, and anticancer activities have been identified. Our approach features a tandem carbonylative Stille cross coupling and Diels‐Alder reaction to forge a key C—C bond and build thetrans‐decalin system. This tandem process utilizes carbon monoxide as a one‐carbon linchpin to stitch a vinyl triflate and a vinylstannane together and form the desired enone moiety for the subsequent intramolecular Diels‐Alder cyclization. Our synthesis also provides a versatile approach for the synthesis of other related pyrrolizidinone‐containing polyketides.
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- PAR ID:
- 10442593
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chinese Journal of Chemistry
- Volume:
- 41
- Issue:
- 22
- ISSN:
- 1001-604X
- Format(s):
- Medium: X Size: p. 3019-3024
- Size(s):
- p. 3019-3024
- Sponsoring Org:
- National Science Foundation
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