Asymmetric synthesis of indolo[2,3-a]quinolizidin-2-ones - congeners to yohimbine-type alkaloids
作者:Herbert Waldmann、auMatthias Braun、Markus Weymann、Markus Gewehr
DOI:10.1016/s0040-4020(01)80309-4
日期:1993.1
Schiff bases derived from tryptophan methyl ester and tryptamine react with Danishefkys diene in the presence of ZnCl2 to give enaminones which are subsequently transformed into indolo[2,3-a]quinolizidin-2-ones by acid-catalyzed cyclization. These tetracyclic aminoketones serve as viable intermediates in the construction of complex alkaloids, e. g. reserpine and deserpidine, and analogues thereof.