Total Synthesis of 4-Azaeudistomin Y1 and Analogues by Inverse-ElectronDemand Diels-Alder Reactions of 3-Aminoindoles with 1,3,5-Triazines
摘要:
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.
Total Synthesis of 4-Azaeudistomin Y1 and Analogues by Inverse-ElectronDemand Diels-Alder Reactions of 3-Aminoindoles with 1,3,5-Triazines
摘要:
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.
A highlyenantioselective C2 Friedel–Crafts alkylation reaction of 3-substituted indoles to β,γ-unsaturated α-ketimino esters has been developed. This reaction was efficiently catalyzed by a chiral phosphoric acid catalyst. The corresponding C2-substituted indole derivatives, bearing an α-ketimino ester motif, were obtained in moderate to high yields (up to 93%) and with high enantioselectivities (up
Three-component reaction involving metal-free heteroannulation of N-Boc-3-amido indole, aryl aldehydes, and aromatic alkynes under microwave conditions: synthesis of highly diversified δ-carbolines
作者:Sudhir K. Sharma、Anil K. Mandadapu、Mohammad Saifuddin、Sahaj Gupta、Piyush K. Agarwal、Ashok K. Mandwal、Harsh M. Gauniyal、Bijoy Kundu
DOI:10.1016/j.tetlet.2010.09.054
日期:2010.11
An efficient synthesis toward highly diversified delta-carbolines via one-pot multicomponent reaction using N-Boc-3-amido indoles, aryl aldehydes, and aromatic terminal alkynes under microwave conditions has been described. (C) 2010 Elsevier Ltd. All rights reserved.