Biomimetic total synthesis of gracilioethers B and C
Matthew D Norris1, Michael V Perkins, Erik J Sorensen
1School of Chemical and Physical Sciences, Flinders University , GPO Box 2100, Adelaide, SA 5001, Australia.
Abstract:
Total syntheses of the marine polyketide metabolites gracilioethers B and C have been realized in 9 steps (40% overall yield) and 10 steps (34% overall yield), respectively. The [2(5H)-furanylidene]ethanoate (furanylidene) motif was constructed in a transacetalization/dehydration cascade of an advanced β-ketoester intermediate, which was designed to mimic a postulated biosynthetic precursor to the natural products. The relative and absolute configurations of gracilioethers B and C are confirmed as (6R,8R) and (6R,8R,11S), respectively.
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