A biomimetic cascade for the formation of the methyl [2(5H)-furanylidene]ethanoate core of spongosoritin A and the gracilioethers

作者：Norris Matthew D; Perkins Michael V^*

来源：Tetrahedron, 2013, 69(46): 9813-9818.

DOI：10.1016/j.tet.2013.09.006

• Gracilioether
• Methyl [2(5H)-furanylidene]ethanoate
• Cyclisation/dehydration cascade
• Sodio-lithio dianion enolate

The polyketide secondary metabolites spongosoritin A and gracilioethers A-C contain a unique methyl [2(5H)-furanylidene]ethanoate core. A synthetic model of a suspected biosynthetic intermediate to these natural products was constructed in seven steps and 48% overall yield. This model undergoes a facile cyclisation/double dehydration cascade to give the desired furanylidene motif, with the required (2Z) isomer obtained in %26gt;90 dr when an ethyl substituent is located at C3%26apos; of the furanylidene.

• 出版日期2013-11-18