Journal ArticleTotal Synthesis of <scp>UCS1025A</scp> via Tandem Carbonylative Stille Cross Coupling and <scp>Diels‐Alder</scp> Reaction ^†Cui, Chengsen; Dai, Mingji<title>Comprehensive Summary</title> <p>We report an efficient and convergent strategy for the total synthesis of UCS1025A and its diastereomer tetra‐<italic>epi</italic>‐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 the<italic>trans</italic>‐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.<inline-graphic href='graphic/cjoc202300331-gra-0001.png' title='image'/></p>Wiley2023-11-1510529695Chinese Journal of Chemistry41223019 to 30241001-604Xhttps://doi.org/10.1002/cjoc.2023003312102022; 2242508National Science Foundation