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Bioinspired Asymmetric Total Synthesis of Emeriones A-C.

ABSTRACT: We report asymmetric bioinspired total syntheses of the fungal metabolites emeriones A-C via stereoselective oxidations of two bicyclo[4.2.0]octadiene diastereomers. The central bicyclic scaffolds are prepared in an 8π/6π electrocyclization cascade of a stereodefined pentaene, which contains the fully assembled side chains of the emeriones. The anti-aldol side chain is made using a Paterson-aldol addition, and the epoxide of the dioxabicyclo[3.1.0]hexane side chain via ring-closure onto an oxidized acetal. Our work has enabled the structural revision of emerione C, and resulted in the synthesis of a "missing" family member, which we call emerione D. DFT calculations identified two methyl groups that govern torquoselectivity in the 8π/6π cascade.

SUBMITTER: Janner S

PROVIDER: S-EPMC9401028 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Bioinspired Asymmetric Total Synthesis of Emeriones A-C.

Jänner Sven S Isak Daniel D Li Yuli Y Houk Kendall N KN Miller Aubry K AK

Angewandte Chemie (International ed. in English) 20220628 32

We report asymmetric bioinspired total syntheses of the fungal metabolites emeriones A-C via stereoselective oxidations of two bicyclo[4.2.0]octadiene diastereomers. The central bicyclic scaffolds are prepared in an 8π/6π electrocyclization cascade of a stereodefined pentaene, which contains the fully assembled side chains of the emeriones. The anti-aldol side chain is made using a Paterson-aldol addition, and the epoxide of the dioxabicyclo[3.1.0]hexane side chain via ring-closure onto an oxidi ...[more]

PMID: 35670768

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