Bioinspired Asymmetric Total Synthesis of Emeriones A–C

Abstract

We report an asymmetric bioinspired total synthesis of the fungal metabolites emeriones A–C via stereoselective late-stage epoxidation or endoperoxidation of two bicyclo[4.2.0]octadiene diastereomers. The central bicyclic scaffold is synthesized in an 8pi/6pi electrocyclization cascade of a stereodefined (E,E,Z,Z,E)-pentaene, which contains the fully assembled and unprotected side chains of the natural products. The pentaene is constructed convergently through Stille cross-coupling of two similarly complex polyenes. The anti-aldol side chain of the emeriones is made using a Paterson-aldol approach, and the epoxide of the dioxobicyclo[3.1.0] side chain is synthesized via an unusual ring-closure onto an oxidized para-methoxyphenyl acetal. Our total synthesis has enabled the revision of the structure of emerione C and the synthesis of a “missing” family member, which we hereby call emerione D.

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“…A set of recent works have investigated the potential of diffusion models in robotics [39,40,41,42,43,44,45,46,2,47]. Research demonstrates that diffusion models can generate multimodal distributions over actions [41] and can handle spatial ambiguities in symmetric objects [2].…”