Total synthesis of ascospiroketal a through a Ag(I) -promoted cyclization cascade
Stanley Chang1, Soo Hur, Robert Britton
1Department of Chemistry, Simon Fraser University, Burnaby, British Columbia (Canada).
Abstract:
The total synthesis of four candidate stereostructures for the marine octaketide ascospiroketal A have been achieved. These concise and highly stereocontrolled syntheses feature a unique Ag(I) -promoted cyclization cascade involving an oxetanyl ketochlorohydrin to access the entire tricyclic core of the natural product in one step. These syntheses also establish the full stereochemistry for the ascospiroketal natural products.
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