Enantioselective synthesis of (S)-2-amino-3-phosphonopropionic acid, (S)-AP-3, and (R)-2-amino-4-phosphonobutanoic acid, (R)-AP-4, via diastereoselective azidation of (4R,5R)-trans-N-[(diethoxyphosphoryl)propionyl]- and (4R,5R)-trans-N-[(diethoxyphosphoryl)butanoyl]hexahydrobenzoxazolidin-2-one
作者:Gloria Reyes-Rangel、Virginia Marañón、C. Gabriela Avila-Ortiz、Cecilia Anaya de Parrodi、Leticia Quintero、Eusebio Juaristi
DOI:10.1016/j.tet.2006.06.018
日期:2006.8
N-Acylation of readily available, enantiopure oxazolidinone (4R,5R)-1b with (diethoxyphosphoryl)propionyl chloride and (diethoxyphosphoryl)butanoyl chloride affords de title substrates (4R,5R)-2 and (4R,5R)-7, respectively, which are azidated with high diastereoselectivity by means of the reaction between their sodium enolates (4R,5R)-2-Na and (4R,5R)-7-Na with trisyl azide. Removal of the chiral auxiliary from azidated products (4R,5R,2'S)-3 and (4R,5R,2'R)-8 followed by hydrogenation and hydrolysis of the resulting carboxylic acids (S)-4 and (R)-9 gave the pharmacologically relevant aminophosphonic acids (S)-AP-3 and (R)-AP-4 in good yield. (c) 2006 Elsevier Ltd. All rights reserved.