Regiospecific Syntheses of 3-Aza-alpha-carbolines via Inverse Electron-Demand Diels-Alder Reactions of 2-Aminoindoles with 1,3,5-Triazines

The 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-alpha-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 various 3-aza-mescengrincin analogues that may possess neuroprotective activities.