Quinolizidines. XXXIII. A Chiral Synthesis of (-)-Ophiorrhizine, a Pentacyclic Quaternary Indole Alkaloid from Ophiorrhiza major RIDL.
作者:Tozo FUJII、Masashi OHBA、Shigeki SETO
DOI:10.1248/cpb.43.49
日期:——
A detailed account is given of the first chiral synthesis of the Ophiorrhiza alkaloid ophiorrhizine [(-)-1]. The synthesis was started by coupling the lactim ether (+)-4, readily available from cincholoipon ethyl ester [(+)-3], with 6-benzyloxy-3-chloroacetylindole (6) to form the lactam ketone (+)-8 and proceeded through the intermediates (+)-9, (+)-10, 11, (-)-12, (-)-13, 14, (-)-15, and (-)-16. The identity of synthetic (-)-1·H2O with natural ophiorrhizine unequivocally established the absolute stereochemistry of this alkaloid.
本文详细介绍了首次手性合成麦冬草生物碱麦冬草素[(-)-1]的过程。合成的第一步是将内酰胺醚 (+)-4 与 6-苄氧基-3-氯乙酰吲哚 (6) 偶联,形成内酰胺酮 (+)-8,并通过中间体 (+)-9、(+)-10、11、(-)-12、(-)-13、14、(-)-15 和 (-)-16 继续进行。合成 (-)-1-H2O 与天然麦角碱的同一性明确地确定了这种生物碱的绝对立体化学结构。