Use of the Oxazole-Olefin Diels-Alder Reaction in the Total Synthesis of the Monoterpene Alkaloids (-)-Plectrodorine and (+)-Oxerine
作者:Masashi Ohba、Rie Izuta、Emi Shimizu
DOI:10.1248/cpb.54.63
日期:——
the total synthesis of two monoterpene alkaloids, (-)-plectrodorine [(-)-1] and (+)-oxerine [(+)-3], is presented. The key steps involved are the formation of the oxazole alcohol 10 from the gamma-butyrolactone 9 and the intramolecular Diels-Alder reaction of the oxazole-olefins 13a, b. Since the sign of specific rotation for the synthetic (+)-3 was different from that reported for natural oxerine,
提供了两个单萜生物碱,(-)-plectrodorine [(-)-1]和(+)-oxerine [(+)-3]的总合成的完整说明。所涉及的关键步骤是由γ-丁内酯9形成恶唑醇10和恶唑-烯烃13a,b的分子内Diels-Alder反应。由于合成(+)-3的比旋转迹象与天然草皮的报道不同,因此尚未完全了解这种生物碱的绝对构型。