Use of azalactones in a “Pictet-Spengler-like” reaction. Stereoselective synthesis of 1,3,4-substituted tetrahydro-β-carbolines
作者:Jesús Ezquerra、Carlos Lamas、Alfredo Pastor、Pilar Alvarez、Juan José Vaquero、Will G Prowse
DOI:10.1016/0040-4039(96)01233-6
日期:1996.8
A “Pictet-Spengler-like” reaction between azalactones 1 and conformationally constrained tryptamines 4 in refluxing 1N HCl over 72 h. gave the corresponding tetrahydro-β-carbolines 3 in moderate to good yields. The observed equatorial orientation of the C-1 substituent in the THBC's results from a combination of the thermal reaction conditions and conformational constraints imposed by the starting
Stereoselective synthesis of 1,3,4-substituted tetrahydro-β-carbolines from indoles based on selective transformations
作者:Jesús Ezquerra、Concepción Pedregal、Carlos Lamas、Alfredo Pastor、Pilar Alvarez、Juan José Vaquero
DOI:10.1016/s0040-4020(97)00489-4
日期:1997.6
nucleophilic aziridine ring opening with a lower order indolyl magnesium cuprate obtaining the α,β-substituted tryptamines 5 and secondly, a “Pictet-Spengler-like” reaction between azalactones 12 and tryptamines 5. Under the acidic reaction conditions used, the thermodynamically favoured tetrahydro β-carbolines 4 are obtained due to the conformational restrictions imposed by the tryptamine substituents