Total Synthesis of 4-Azaeudistomin Y1 and Analogues by Inverse-ElectronDemand Diels-Alder Reactions of 3-Aminoindoles with 1,3,5-Triazines
作者:Qun Dang、Xu Bai、Guoxing Xu、Lianyou Zheng
DOI:10.1055/s-0032-1316857
日期:——
A new inverse-electron-demand Diels-Alder (IDA) reaction of 3-aminoindoles as dienophiles was developed for the efficient preparation of 4-aza-beta-carbolines in high yields. Because N-1-unprotected 3-aminoindoles show poor thermal stability, a one-pot protocol was developed that combines the removal of tert-butoxycarbonyl protecting groups with the IDA reaction. This protocol, using tert-butyl 1H-indol-3-ylcarbamates as reactants, gave the corresponding IDA products in excellent yields. The new IDA methodology was used in a total synthesis of 4-azaeudistomin Y-1, which was obtained in 57% overall yield in four steps. Moreover, the chemistry is suitable for the rapid preparation, through either Friedel-Crafts acylation or amide-formation reactions, of analogues that are useful for exploring structure-activity relationships at the C-1-position.
Regiospecific Syntheses of 3-Aza-α-carbolines via Inverse Electron-Demand Diels-Alder Reactions of 2-Aminoindoles with 1,3,5-Triazines
作者:Qun Dang、Xu Bai、Guoxing Xu、Lianyou Zheng、Shixue Wang
DOI:10.1055/s-0029-1218345
日期:2009.12
scope of 1,3,5-triazine inverse electron-demand Diels-Alder (IDA) reactions was expanded to include 2-aminoindoles as productive dienophiles leading to various 3-aza-α-carbolines in excellent yields. Furthermore, the two ester groups of the IDA product were differentiated via reduction of the C4-ester to its corresponding alcohol. This new IDA reaction could be potentially applied to the synthesis of