8-Carbolines—continued synthesis

Interest continues to be shown in the synthesis of eburnamonine and vincamine owing to their useful pharmacological properties. In their synthesis of eburnamonine, Szantay and his collaborators" adopted the annelation reaction between 3,4-dihydro-/3-carboline and an appropriate enone for the purpose of constructing the tetracyclic intermediate (207) (Scheme 32) both epimers of (207) were obtained. These were separated, and the synthesis was completed with both epimers. A synthesis of both eburnamonine and isoeburnamonine was thus reported only that leading to eburnamonine is illustrated. 

Shulgin A, Shulgin A (1997) TiHKAL the continuation. TransformPress, Berkeley, pp 713-714 Airaksinen MM, Kari I (1981) Beta-carboline, psychoactive compounds in the mammalian body. Part I Occurance, origin and metabolism. Med Biol 59 21-34 Toma T, Kita Y, Fukuyama T (2010) Total synthesis of (-i-)-manzamine A. J Am Chem Soc... 

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