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Total Syntheses of the Reported Structures of Curcusones?I and J through Tandem Gold Catalysis.

ABSTRACT: Total syntheses of the reported structures of the rhamnofolane diterpene natural products curcusones?I and J in racemic form were achieved. The synthetic strategy features a novel tandem gold-catalyzed furan formation and furan-allene [4+3] cycloaddition to build the 5,7-fused ring system with an oxa-bridge in one step, and a stereoselective exo-Diels-Alder reaction to form the 6-membered ring. The newly developed tandem gold catalysis is quite general and can be scaled up. Our syntheses suggest that structural revisions of curcusones?I and J are needed.

SUBMITTER: Li Y

PROVIDER: S-EPMC5682107 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Total Syntheses of the Reported Structures of Curcusones I and J through Tandem Gold Catalysis.

Li Yong Y Dai Mingji M

Angewandte Chemie (International ed. in English) 20170810 38

Total syntheses of the reported structures of the rhamnofolane diterpene natural products curcusones I and J in racemic form were achieved. The synthetic strategy features a novel tandem gold-catalyzed furan formation and furan-allene [4+3] cycloaddition to build the 5,7-fused ring system with an oxa-bridge in one step, and a stereoselective exo-Diels-Alder reaction to form the 6-membered ring. The newly developed tandem gold catalysis is quite general and can be scaled up. Our syntheses suggest ...[more]

PMID: 28708291

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