Al-Tel Taleb H, Al-Qawasmeh Raed A, Sabri Salim S, Voelter Wolfgang
College of Pharmacy, University of Sharjah, P.O. Box 27272, Sharjah, UAE.
J Org Chem. 2009 Jul 3;74(13):4690-6. doi: 10.1021/jo900192a.
Regio- and chemoselective syntheses of enantiopure bis-furanoids are described. These compounds are chirons for several families of bioactive natural products, including isoavenaciolide and ethisolide. Reaction of a 3,4-epoxy pyran with beta-ketoester dianions delivers substituted pyranosides in high yield. Cyclization then yields fused furan-pyran intermediates. Oxidation, deprotection, and rearrangement lead to bis-furanoids that bear the essential framework and stereochemistry of ethisolide and isoavenaciolide.
本文描述了对映体纯双呋喃类化合物的区域选择性和化学选择性合成。这些化合物是几类生物活性天然产物的手性合成子，包括异燕麦内酯和乙草内酯。3,4-环氧吡喃与β-酮酯二价阴离子反应可高产率得到取代的吡喃糖苷。然后环化生成稠合呋喃-吡喃中间体。氧化、脱保护和重排得到具有乙草内酯和异燕麦内酯基本骨架和立体化学的双呋喃类化合物。
